# $10 Servo Controller



## fritz42_male

Here is a link to my $10 Servo Controller Howto. This is a work in progress so I'd appreciate feedback (especially from hpropman who inspired me in the first place and who has been generous with providing a code example for a random head movement program).

www.ipprofessional.com.au/VLC Servo Controller.pdf

Picaxes, boards and kits can be bought from

US - Sparkfun. http://www.sparkfun.com/commerce/product_info.php?products_id=8321

UK - Tech Supplies. http://194.201.138.187/epages/Store...h=/Shops/Store.TechSupplies/Categories/PICAXE

AUS - Microzed. http://www.microzed.com.au/

NZ - http://www.kei.co.nz/

And so on.


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## Dr Morbius

Cool! So these are programmed on a PC then stored in memory? IS there memory? How does this work exactly?


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## bradbaum

Programming is similar to a prop1 from efx-tek.

however the picaxe is just a chip, so you need a circuit board of some type.

Programing is through a cable (like the prop1).

And yes it has internal memory to store the compiled program.


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## hpropman

It looks good so far. The only thing to be careful about this board is that you have to make sure that you give it 5 volts no more or you may damage the chip. Also I do not see a separate power input for the servos if you want to use 6 volts. Phaderson has a protoboard that is in the same price range that has a 5 volt regulator on the board and you can get it assembled already if you want it is also available in kit form as well. I think that that board might be a better choice for something like this. the only drawback to that board is that the programing connector is a 9 pin serial connector. One last option is this board:

http://acronum.com/nz-en/index.php?...n=com_virtuemart&Itemid=54&vmcchk=1&Itemid=54

It has the 5 volt regulator circuit and the picaxe programming circuit using the 3.5 MM plug already It may drive the price up a little bit but it will save someone from applying a voltage greater than 5 volts and possible damaging a chip. I do not not mean to sound overly critical but I just thought you should be made aware of these possibilities. Many people who might try to use these might not be as savvy in electronics at first. This might save them from damaging a chip and getting frustrated and giving up. Just something to be mindful of.


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## fritz42_male

Hi Propman,

The proto board has a separate supply for the servo connectors (top left of the board). I wanted this one to be really easy so I've assumed that people will use a 4.5V (3xAA) battery pack for the Picaxe and a 6V (4xAA) supply for the servos. The port 3 connector is hardwired to the 4.5V supply for switched inputs like PIR, mats etc.

I've got a pile of the Acronum boards on order already and will be using this for the revision 2 version but the above version is cheap, easy to build and might solve a few immediate problems for people wanting a simple servo drive. This is the first part of the article - the next part will link in Solid State Relays and so on.

This board works great with your random head movement code and I have it running a single servo off the same supply as the Picaxe with no problems.

I also want to see if I can get it to emulate the SSC boards!


Have you got a link to the phaderson protoboard?

I'm hoping that in revision 2 I'll be able to build in 12/24V relay (or even higher current) drive as well as more servo ports. Ultimately I want a CHEAP adaptable board that can take an 08M, 14M and 20X2 as well (when it's available)


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## hpropman

He is on vacation now so he does not have them up on the board at the moment. Here is the link to his page this is what I started with.

http://www.phanderson.com/picaxe/

You can see the board on the way back machine here I am sure when he gets back he will restore the store to full selection again.

http://web.archive.org/web/20080130154441/http://www.phanderson.com/picaxe/


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## fritz42_male

Thanks Joe


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## Dr Morbius

Sorry for the ?'s guys, But exactly how much memory can these things store? how long can a program be, controlling all 4 servos at once for example?


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## fritz42_male

On the 08M and 14M not that big a program - 80 lines total although there are ways of crunching programs down a bit. This is enough for a lot of things though such as random head servo movements, sound to jaw movement (a coming project), timer control, pulsing eyes and so on.

I'm also hoping to write an interface program to make it look like a mini-SSC controller so that it can be controlled by other things like VSA.

I like compartmentalising things so the way I see this setup working is that you use a VLC for each 'thing' you want to do. So a talking skull with head and eye movement might involve 3 VLC controllers each doing their own thing.

Install the driver software on a PC, plug the cable into your PC and the board, write and download the program and watch it go!


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## hpropman

The newer chips can program sizes of about 1000 lines and are much faster chips the 20X2 can run at 64MHZ the 08M can only run at 4MHZ or 8Mhz.


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## DarkLore

If I understood all this....my opinion would be that I'd rather see a solution for the phanderson protoboard, mentioned above. I'd hate to build out a board and burn it out because I didn't remember what power to hook to the connector.

I hate the thought of powering servos off a separate power supply. I want one connection for a power supply...so that the board takes care of powering the servos. And the option to have the board pre-made. I've got so many projects going, I don't have time to solder up more boards.


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## fritz42_male

That will be the next one I'm working on. Onboard regulator for driving a couple of servos plus some higher current devices via a darlington array.
.


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## pshort

What are the usual requirements for the control signal for a hobby servo? TTL levels, or something else?


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## hpropman

The servo is controlled by pulses that need to be sent every 20ms for the servo to maintain its position. The servo positions itself based on the width of positive pulses fed to it. A pulse width of 1.5 milliseconds positions the servo at its center, a width 1 millisecond and 2 milliseconds being the accepted limits to either side. the controller board inside the servo reads the pulses then moves the motor to the position bases on the width of the pulse at that moment. If the servo is at a particular position that is not the center then to maintain that position the same width of pules that correlate to that position must be sent to the servo at least every 20 ms (milliseconds). If the pulse width changes then the servo will move to the new position again based on the width of the pulse at that moment. The red and black wires are just the power wires. The picaxe uses a command called servo followed by the pin and the position you want the servo to be at. The picaxe will hold the servo at that position until it is told to move it somewhere else. It does all the pulse work for you you just tell it where to go and how long you want it to stay there. It makes working with servos very easy. The most common use for a servo is to drive a mouth to track voice. If you look at the picaxe program below any thing after a ; is a comment. This is the program that I use to move the mouth on my skulls. the voice is fed into the sound circuit and then converted into pulses with correlate to spoken syllables. The pulses are then fed into the picaxe to open and close the mouth to mimic speech. I know it seems like a lot to comprehend but please ask if you have any questions I will try to explain it better. 

input 1 ;set pin 1 to input
servo 2,150 ;set mouth to the start position and then open and close the mouth
pause 1000 
servo 2,77
pause 1000
servo 2,210
pause 2000

closed: ;code to close the mouth 

servo 2,210
pause 30
goto loop

loop:

if pin1 = 0 then open ; if pin 1 goes low (from the sound circuit) then open the mouth 
goto loop ;continue to check for sound

open: 

servo 2,170 ; open the mouth
pause 4 ; Slight delay 4ms kepps the mouth from chattering

check: 

if pin1 = 1 then closed ;check to see if there is still sound if not then goto close mouth
pause 1 ; small pause
goto check


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## pshort

I was asking about the required voltages and currents for the control signal to the servo.

Edit - I am fully aware that this signal is digital in nature, and consists of high-going pulses of various duration and repetition rates. What I wish to get some idea of is what are the low and high voltage thresholds of these pulses, and how much current does this digital input sink and source.


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## hpropman

Sorry I misunderstood. TTL levels 5 volts - the chip can source 20ma so that is your current limit for the pulse train. the servo motor itself through the red and black wires will draw a lot more current. I never measured it but I doubt is is more than a few hundred milliamps. Here is the specs for a typical servo.

http://www.servocity.com/html/s3004_standard_ball_bearing.html


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## fritz42_male

Although the control signal is data level (3.3 to 4.5 V) and very low current, the servo power itself can be anything from 4.5 to about 7.5 volts. It draws up to 1 Amp under load.


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## pshort

Thanks, and sorry for hi-jacking the thread.

Anyway, a Cirrus CS601BB seems to run fine with a 3V signal (sample of one part, running for only a minute or two before the batteries died). I'm working on a little 0.6" x 0.6" single-channel controller using a PIC10F series part and a serial EEPROM for program storage and one digital input. The EEPROM wants to run off 2.7-3.3V, which pretty much sets the voltage for the PIC (and hence the control signal to the servo).


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## fritz42_male

How much program space do you need because the picaxe 08M is tiny and all you need in support circuitry is a few resistors. It has a reasonable amount of program storage built in.


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## pshort

Sorry I didn't answer sooner, we drove down to Legoland in Carlsbad,CA yesterday. That's a nice park, and we enjoyed it a lot.

There aren't any specific requirements at the moment, just the feeling that the amount of EEPROM in any of the low-end PICs is a bit small. My usual source for information (wikipedia) says that the PICAXE-08M has 256 bytes of EEPROM, which leads me to think that it might be a PIC12F683. In any case, the device that I'm working has 64Kb of EEPROM storage, which is quite a bit more than 256 bytes.

Most of the designs that I've done over the last few years have catered to computer-controlled animated Christmas Displays. This project was originally intended as a standalone controller for driving a chain of 75HCT595 controllers in simple on/off manner, which requires a lot more memory than any PIC10F/PIC12F part provides for a multi-minute sequence.

The firmware that I'm working on at the moment strongly caters to a servo-control application rather than the general purpose nature of the PICAXE. One specific memory location is used for the servo angle, with hard-coded firmware to send the pulses to the servo.


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## DarkLore

*Servo Controller*

I've placed an order w/SparkFun. I'm presuming this is a good solution for props like my Mourning Wood Stew prop.



fritz42_male said:


> Here is a link to my $10 Servo Controller Howto. This is a work in progress so I'd appreciate feedback (especially from hpropman who inspired me in the first place and who has been generous with providing a code example for a random head movement program).
> 
> www.ipprofessional.com.au/VLC Servo Controller.pdf


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## fritz42_male

DarkLore said:


> I've placed an order w/SparkFun. I'm presuming this is a good solution for props like my Mourning Wood Stew prop.


Yup - sure is. Ask hpropman for his random head movement code.

I'm just about to use some of his eye LED code for making a board with multiple LED eyes - that one is based on the Pixaxe 14 chip with a darlington driver array so I can drive more LEDs


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## hpropman

Absolutely the picaxe will handle this easily. I have not see a prop yet that can not be controlled or made better by a picaxe. I just love them for there ease of use and price. The 08M should be all that you need. However if you need more I/O pins there is always the 14M and 20M. The line goes all the way up to a 40X2 which is so overkill for a prop controller is it not funny. The reason that they are so cheap is because the R & D was paid for by the oil industry as an education grant. The picaxe is used in many school technical and robotics programs.


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## pshort

fritz42_male said:


> I'm just about to use some of his eye LED code for making a board with multiple LED eyes - that one is based on the Pixaxe 14 chip with a darlington driver array so I can drive more LEDs


It must be that time of year, as I'm doing more or less the same thing for a buddy. The firmware is written in PIC assembly language for a PIC16F688 (a 14-pin micro, perhaps the same part as the PICAXE14M), while he is home-etching a PCB with discrete transistors. From this point on the difficult part will be tweaking the firmware to make the light trails behind the moving eye look good. And if that doesn't work out good, I might consider re-doing the firmware to use charlie-plexing to make that 14-pin micro drive more LEDs, perhaps as many as 24.

It is easy for me to write in PIC assembly language, so I've never had any incentive to use the PICAXE parts. Not that I think that there is anything wrong with the PICAXE solution, just that I do things a different way.


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## fritz42_male

Assembly language - hmmmm that's difficult stuff and I never had the patience to delve into it.

As for trails, why not just stick a decent size electrolytic capacitor on the output to the LEDs - they will fade gradually as they use up the stored power. Sometimes simple solutions are best!


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## pshort

Is the PICAXE 08M capable of driving multiple servos at the same time?


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## hpropman

yes it can handle up to 3 servos. Here is a board that does just that:

http://www.robotshop.us/picaxe-08m-servo-driver-kit-axe024-3.html

BTW the 20X2 has just been released. It has configurable I/O pins (so that can be either input or outputs) and with speeds up to 64MHZ it has some horsepower. The 08m runs at 4MHZ for comparison.


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## fritz42_male

'My' board drives up to 4 servos but you have to change a jumper.

Just waiting for my 20x2 - already started a protoboard for it based on the Kiwi-PCB


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## fritz42_male

If anyone is interested, I have the $10 controller working as a delay/duration timer with optional switch activation. All it needs is a couple of 10K linear pots and an SSR


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## hpropman

cool! have any pics?


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## fritz42_male

Will take some today. I had to bypass the 330 ohm resistor on one of the outputs so that the SSR would activate. Otherwise no problem.

So far the Picaxe count is as follows:

$10 board as random head movement servo driver
$10 board as delay/duration timer for my smoke machine
$15 Axe117 board as random LEDs for eye lights in a tree

These things really are handy and easy! I might modify your random head movement code and build in activation plus timed response so that my Reaper Greeter doesn't start moving his head until he starts speaking and stops moving his head when he is finished.

Code for the last 2 is as follows:

Delay/Duration Timer

symbol delay=1
symbol duration=2

begin:


b2 = 0
Do
ReadAdc delay, b1
Pause 100
b2 = b2 + 1
Loop Until b2 >= b1

high 0
high 4

b3 = 0
Do
ReadAdc duration, b4
Pause 100
b3 = b3 + 1
Loop Until b3 >= b4

low 0
low 4

goto begin



Random LED Eyes

symbol led0 = 0
symbol led1 = 1
symbol led2 = 2
symbol led3 = 3
symbol led4 = 4
symbol led5 = 5

main:
startup:
high led0
high led1
high led2
high led3
high led4
high led5
pause 2000
low led0
low led1
low led2
low led3
low led4
low led5

goto flash

flash:
Random w0
Random w1
w2 = w0 / 80
w3 = w1 / 11
if w3 < 1000 then: high led0
pause w2
low led0
elseif w3 < 2000 then: high led1
pause w2
low led1
elseif w3 < 3000 then: high led2
pause w2
low led2
elseif w3 < 4000 then: high led3
pause w2
low led3
elseif w3 < 5000 then: high led4
pause w2
low led4
elseif w3 < 6000 then: high led5
pause w2
low led5



endif
goto flash


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## fritz42_male

Here's a couple of pics. Finished box has an on/off switch with LED indicator then delay/duration pots, active LED (for when the smoke machine is firing) and an override button so I can activate the smoke machine manually.

Cost was about $25 to build which isn't bad because I can't find one in Oz for anything less than $100!


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## DarkLore

The problem you don't state - if you start one of these and don't get it working...it's no longer $10. The time investment to solder these things up is not small.


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## fritz42_male

Darklore,

I've now put together 4 of the $10 boards, 2 of the Axe 117 boards, 5 Kiwi Patch boards and 1 Axe020 board - not one has failed to work.

I've made a few mistakes along the way, caused tracks to lift on on a $10 board (through overheating it with the soldering iron) and chopped the end off it and used it on a normal veroboard, I've wired up the servos the wrong way on another board and caused the 08M to overheat and THEY STILL WORK!

I built the last $10 board following my own howto to the letter to see if I could see where errors have crept in and it worked perfectly. So I'm sorry that you are having trouble but I also believe that learning from mistakes is one of the best ways to learn.

I also timed myself on assembling the last board (I'm not fast due to shaky hands and poor eyesight). It took me 15 minutes to assemble the board with the components as supplied by the manufacturer and another 25 minutes to do the additional work to turn it into the $10 controller. The first board I assembled took 20 minutes for the manufacturers bits and 5 minutes playing with the software to download a program - hardly a major investment in time!

I've also responded to every PM you have sent me regarding this and tried to help.


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## hpropman

How can time spent on a Hobby you enjoy be a problem. I will admit sometimes when things do not work the first time it can be frustrating but also more rewarding when you get it work. Darklore what problem are you having? Maybe I can help you fix it.


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## pshort

I think that it's better to do troubleshooting in the open, rather than through pm. More people can help, the problem can be seen from more perspectives, and it's useful to help others in the future with similar difficulties. It has worked fine in another forum that I've been involved in, and the people here seem civil enough for it to work here as well.


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## DarkLore

hpropman said:


> How can time spent on a Hobby you enjoy be a problem. I will admit sometimes when things do not work the first time it can be frustrating but also more rewarding when you get it work. Darklore what problem are you having? Maybe I can help you fix it.


I didn't mean for my comment to come off as a big negative...just a warning to people like me who don't do much of this. Sometimes these threads sound like infomercials.

Fritz has been helpful. I haven't gotten back to the picaxe boards because of other projects with the Halloween deadline closing in.


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## fritz42_male

Thats OK and I know about deadlines - getting a bit panicky about mine!

The others are right about keeping things in a thread though, I tend to do most of my chatting 'in forum' rather than via PMs as it's far more informative for all.

All I can say about the Picaxe chips is that they are VERY robust and if you have the resistors correct for the communications and the chip plugged in the right way then it should work. If it doesn't communicate then it's more likely to be an issue with the serial comms than anything else. I'm in Oz so posting a board to me might be a problem for you but it goes without saying that I'd be happy to take a look.

Please persist with the Picaxe though - they are lovely little chips to work with and are VERY useful for home haunters. Don't get me wrong, the semi-pro controllers like the Prop 1/2, Nerve Centre etc are also needed but for the smaller stuff particularly independent servo control then the Picaxe is very cheap and very easy.

I got into the Picaxe via these forums and almost certainly via hpropman and have not regretted it one bit - in fact it's proven to be a lot of fun (thanks Joe!).


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## DarkLore

_Building circuit boards can be someone else's hobby. Mine is building props. This thing is just a means of controlling it._

Let's start with the following question.

I have a pdf that walks me through a few steps to create the controller. I also have an image to show me better detail of the finished product. Some of those connections are hard to make out in the photo., but I can see that there are differences. Compare the first modification step....(2. Solder the Power Lines)










Note the location of the red wire highlighted below....










The pdf doesn't match the photo. What is the correct connection for that red wire? (I have one board built that matches the pdf...and doesn't work. Another board waiting at this step in case that first one is wired wrong.)


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## fritz42_male

I'm going to deal with your queries at 2 levels - one based on the board that you haven't made up yet and one on the board you have made up.

Unmade board:
Let's go right back to first principles and determine if you can get communications running on an unmodified board. Assemble the second board with the bits as supplied by the manufacturer and then try downloading a program to it (doesn't matter what the program is, we are just trying to verify communications). If the program downloads then the board is working this far.

Made board
If you look at your bare board you will see that the legend on the board shows that the holes are linked horizontally in groups of 3 - this means that there is a layer which links these holes together. I centred each 3 pin connector vertically in the centre of this group of 3 horizontal holes. The aim is to initially get ground linked to the base of each 3 pin connector and power linked to the next pin up - the exception to this is the port 3 connector (the middle one on the top row) which is different because I had an idea about this that I will come to later.

The red wire you have highlighted can go to EACH side of the port 4 connector. My hands shake and when I assembled ths board, I just found it easier to link the wire on the right hand hole as opposed to the left hand hole. Since both of these holes are linked together, the actual position doesn't matter. The red wire takes power from the auxiliary power connector (the leftmost connector on the top row) to the right most connector (port 4).

In reality, you could have wired the power lines as below (I know this doesn't help but what I'm trying to say is that this bit isn't particularly critical to the functioning of the board for what you want to do).

If you can get some high-res pictures of both top and bottom of your board then I might be able to see what's wrong.




In general terms, when doing something like this, it's essential to get to the first base which is that of assembling and testing the basic board before going on to modify it to do what you want. Be prepapred to make mistakes - I've messed up a couple of boards. Remember though that the boards themselves are cheap - you can always transfer the chip to a new board. You can (within limits) reuse an old board even if damaged. I had to chop one of my boards off with a hacksaw (as below) and soldered a set of pins in and now use it in a breadboard I have for testing programs and circuits before I build them permanently (the hacksaw suggestion came of Joe - thanks Joe...again & again & again).

It's also handy to try and understand what the designer is trying to accomplish - in this case I perhaps I need to go into more detail in the howto as to what the modifications are for.


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## DarkLore

Made board - I build it beyond the basic picaxe. I was doing as you mentioned....production lining both boards. I just happen to stop on one and proceed with the other.

Red Wire - whoosh is the sound of all that going over my head. I definitely don't want to have to think through this stuff. I get no joy in building these things or figuring out how they work. Ignoring the discussion...I get the part about that wire not caring where its connected.

As for the camera. I have two cameras. I have two teenage daughters. No matter how many times I chew them out for taking my camera...well...I have two teenage daughters...nuff said. Both cameras are at the ex-wife's house. No photos possible.

_"In general terms, when doing something like this, it's essential to get to the first base which is that of assembling and testing the basic board before going on to modify it to do what you want." _ This part I figured out...just too late. Btw...I'm ordering a couple more boards.

_"Be prepapred to make mistakes - I've messed up a couple of boards." _Thus my comment about $10 boards. lol....sorry, couldn't help myself.


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## fritz42_male

No worries but even if you have buggered up a board, it can usually be salvaged for other things. The only thing that seems to screw up a picaxe chip quickly is putting too high a voltage into it. 4.5V to 5V MAX

If you don't want to have to wire things up why not ask Phil if he has any of his servo boards around? These are just solder the components in and away you go.


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## DarkLore

fritz42_male said:


> No worries but even if you have buggered up a board, it can usually be salvaged for other things. The only thing that seems to screw up a picaxe chip quickly is putting too high a voltage into it. 4.5V to 5V MAX
> 
> If you don't want to have to wire things up why not ask Phil if he has any of his servo boards around? These are just solder the components in and away you go.


Phil? Servo boards?


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## fritz42_male

Phil (pshort) has another thread running also with servo controllers. Have a look here:

http://www.hauntforum.com/showthread.php?t=17772

His looks easier to assemble as it is custom designed for servos. Mine is more generic.

I'll be making a few changes to my controller based on his advice - mainly taking out the 330 ohm resistors. If you want me to rewrite my howto, this will simplify wiring one up greatly!

I've got more boards on order - once I get them I don't mind posting you a board to try with one of your existing chips. It will be a tested board. The amended version will allow you to run SSR AC relays directly (without any further mods) so you could also use it as a prop timer.


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## fritz42_male

Darklore, I hate to ask the obvious but is the jumper on your board in the PROG position?


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## DarkLore

Yes. I tried it both ways. I'm wondering if the problem has to do with the computer's serial port. I'm going to test it later today using my computer at work.

I've got one of my cameras back. I'll send a photo later today. I've also got to new boards and chips coming. This time I'll know to test it after the first part of the build.


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## pshort

In light of events, I think that it might be a good idea to change the instructions to have the user test the board and PICAXE _before_ making any modifications. Doing testing before the modifications would eliminate the modifications as the source of a problem, should a problem arise. I'm not sure if this happened here or not.


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## fritz42_male

I agree Phil. Will make the changes to the howto later today. Other than that I'm going to play with lower resistor values until I can get the SSR (or a FET) to fire reliably. Then I'll test the design with servos and then I'll hopefully have a truly 'universal' board.


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## fritz42_male

DarkLore said:


> Yes. I tried it both ways. I'm wondering if the problem has to do with the computer's serial port. I'm going to test it later today using my computer at work.


I've often had serial port problems so it wouldn't surprise me if this is the issue. You bought in the cable right?


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## pshort

fritz42_male,

Which SSRs are you using?


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## pshort

fritz42_male,

Which SSRs are you using?


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## fritz42_male

These. Dirt cheap.

http://cgi.ebay.co.uk/solid-state-r...s_ET?hash=item3ef8a7e45e&_trksid=p3286.c0.m14

Can't find much info though. Typically this style seems to fire on 3V at currents from 10-70mA (don't know how much for this one)

Bear in mind that I tend to use 4.5V batteries to power these boards.


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## DarkLore

fritz42_male said:


> I've often had serial port problems so it wouldn't surprise me if this is the issue. You bought in the cable right?


Good News - as far as I can tell the board works like a champ.

Apparently the serial port on my home computer isn't working properly. I plugged my board (completed) into the serial cable (purchased from sparkfun) and it sees the board without problem. The led test light shows high/low just as it should.

I didn't bring a servo with me to the office...just the board, cable, and battery pack. But everything seems to be fine. The board communicates with the software and has no problem accepting the download of the sample code.

_I had no problem purchasing the serial cable as opposed to USB because I've got plenty of access to computers. _


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## fritz42_male

EXCELLENT!

Do you need the random head movement code for it?

hpropman - OK if I post it here?


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## hpropman

No problem - It was posted in another place on here


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## fritz42_male

Oh yeah - I forgot - my Alzheimers is bad today! lol

Anyway, here it is:

start: symbol counter = b3
symbol pointer = b2
symbol delay = 28
let b2=153 'set pointer offset so that head loop does not get stuck
let b0=150
let b1=150 'set default center values
servo 4,pointer 'center servo
pause 6000
'full motion range test
for counter = 150 to 120 step -2 'move head from middle to right side
servo 4,counter 
pause delay
next counter
'servo 4,120
pause 3000

for counter = 120 to 180 step 2
servo 4,counter 'move head from right to left
pause delay
next counter
'servo 4,180
pause 3000

for counter = 180 to 150 step -2
servo 4,counter 'move head from right to middle
pause delay
next counter
'servo 4,pointer
pause 2000

move: random w0 'place a random number in wo (also B0 & B1)

if b1<100 then left 'check for random left
if b1>=100 and b1<=155 then middle 'check for random middle
if b1>=155 then right 'check for random right
goto move 'keep moving the head back to move loop

right: if pointer = 120 then move 'if head is already Right goto back to move
if pointer = 150 then mr 'check to see if head in pointed middle or the left
for counter = 180 to 120 step -2 'move head from left side to the right side
servo 4,counter
pause delay
next counter
pointer = 120 'set head pointer direction to right
goto skipmr

mr: for counter = 150 to 120 step -2 'move head from middle to right side
servo 4,counter 
pause delay
next counter
pointer = 120 'set head pointer direction to right

skipmr: pause 7000 'delay to look natural
goto move 'return to move loop

middle: if pointer = 150 then move 'if head is already in the middle then go back to move
if pointer = 120 then ml 'check to see if head is pointed left or right
for counter = 180 to 150 step -2
servo 4,counter 'move head from right to middle
pause delay
next counter
pointer = 150
goto skipml

ml: for counter = 120 to 150 step 2
servo 4,counter 'move servo from left to middle
pause delay
next counter
pointer = 150

skipml: pause 9000 'delay to look natural
goto move 'return to move loop

left: if pointer = 180 then move 'if head is already left then return to move
if pointer = 120 then lmr 'check if the head is in the middle or the right
for counter = 150 to 180 step 2
servo 4,counter 'move head from middle to left
pause delay
next counter
pointer = 180
goto skiplmr

lmr: for counter = 120 to 180 step 2
servo 4,counter 'move head from right to left
pause delay
next counter
pointer = 180

skiplmr: pause 7000 'delay to look natural
goto move 'return to move loop


----------



## fritz42_male

And there are tons of PBASIC examples out there that can be used on the Picaxe with little or no modifications.

The EFX-TEK site has some flicker candle examples.


----------



## DarkLore

I got the controller working with my brain jar prop. It doesn't appear that servo one is working. Also...I wired up an led. It lights fine. But the program didn't work. Servos on 2 or 4 work fine. But the led code didn't.

As for the random head movement code. I modified it for what I identified as the range of my brain jar servos....72 min to 98 max. Anything higher and the eye looks too far to an edge. This eye was made from a wooden ball. There's no back. Therefore, moving too far really highlights the fact that my eye isn't a full sphere. For a test, I did this with the vertical servo connected on servo 4.

The problem with the random head code...it only moves unidirectional. An eyeball needs to move up/down, left/right. However....that code appears to come very close to the memory capacity of the board.

I'm guessing a routine that identifies the center as 86, 86...and moves to a random x,y position via a loop...then back to center, would look more natural and fit in memory Basically staring forward...then moving to some visual point in range...then back to center until a random value directs it off again.


----------



## fritz42_male

DarkLore said:


> I got the controller working with my brain jar prop. It doesn't appear that servo one is working. Also...I wired up an led. It lights fine. But the program didn't work. Servos on 2 or 4 work fine. But the led code didn't.
> 
> As for the random head movement code. I modified it for what I identified as the range of my brain jar servos....72 min to 98 max. Anything higher and the eye looks too far to an edge. This eye was made from a wooden ball. There's no back. Therefore, moving too far really highlights the fact that my eye isn't a full sphere. For a test, I did this with the vertical servo connected on servo 4.
> 
> The problem with the random head code...it only moves unidirectional. An eyeball needs to move up/down, left/right. However....that code appears to come very close to the memory capacity of the board.
> 
> I'm guessing a routine that identifies the center as 86, 86...and moves to a random x,y position via a loop...then back to center, would look more natural and fit in memory Basically staring forward...then moving to some visual point in range...then back to center until a random value directs it off again.


If you have an LED on port 1 and it lights up when you issue servo commands then you have a problem with the power line. If nothing at all happens on port 1 then you have a problem with the link from the topmost pin (the signal pin) - either way, look for shorts in your soldering, it's quite easy to accidentally create one when soldering as the spacing on the board is quite small - I had to solder suck a few times and redo some joins.

You can use port 0 for servos as well but you have to remember to move the jumper to the other position and move it back when reprogramming.

Also the 08M has a maximum drive capacity of 90mA - about 3 LEDs. Bear this in mind if using it for LED stuff.

With regard to the random head movement code, when I get time I'll see if I can compress it down. hpropman's code actually increments the servo position by 1 until he hits the maxium for that random number. This slows the servo movement down to make it appear more natural but I'm not sure it's necessary as the servo responses on the 08M seem quite slow anyway.

I'll be trying a few things to give random timing and position within limits.


----------



## hpropman

The code can be optimized by using sub routines and other program shrinking methods. Post the code and we can see about reducing the size of the program

Also you can always step up to a larger chip the 20X2 is now available. It has much larger program space (about 1000 lines of code compared to about 80 with the 08M)


----------



## DarkLore

Will a 20x2 work with the same board?

I'm at work...I don't have the code here. I didn't change much of the original head code. I simply treated it as a one dimensional eye with min 72, midpoint at 86, and max of 98 to see if it would smoothly move the eye. It did.

My guess would be - find two random values between 72 and 98 (one for x, other for y)....loop both directions x,y to smoothly move the servos to a spot....positive incrementing if the servo is at a lower point, negatively incrementing if the servo is at a higher point. Pause a few seconds...then do it again.

My witches cabinet has an animatronic plant in it. For that I'll probably just loop w/a delay to open the mouth, then randomize the length of time its open or closed. Each servo independently.


----------



## DarkLore

lol....okay. I just looked at the site to see what a 20x2 looks like. It obviously doesn't fit the socket. I thought maybe it was a similar chip, just stamped with more memory. It isn't.


----------



## fritz42_male

As you have seen, a 20X2 is a larger chip although the 8m, 14M and 20x2 are pin compatible up to a certain extent. I'm building a new controller based on the Kiwi Patch board coz it's larger with more space, duplicates a breadboard layout and has an onboard regulator.

Your guess re the random code setup sounds OK to me but these days I need to sit down and play (10 years ago, I'd have coded up in my head and it would have probably worked first time!) - trouble is I'm working 6 days a week, 10-12 hours a day for the next month and I have a friend over from the UK so not much free time.


----------



## fritz42_male

Said it before - size IS important. lol


----------



## Dead Things

I know this is an old thread and I hope I'm not off topic on this, but what size of servo's should I be buying. I recieved Dave Corr's Halloween2Go and I want to build the neck mechanism but he doesn't say what size of servo's he uses and going to servo city or hobby partz give me option anxiety. There are literally hundred's of servo's. I too purchased the micro 08 usb based board and I'm hoping to run the 3 servos for the neck and one for the mouth. Can this handle it? And with the sound for the mouth servo what is the best way to do this? Dave Corr uses a Cd player, I'm assuming set to loop. But I don't want the prop triggered in the middle of the "speech". Is there another way to do this, so the speech begins when the prop is triggered?


----------



## halstaff

I just completed building one of Dave's neck mechanisms yesterday. Hi-Tech HS-425BB Servos get added tonight. These are the same servos that many of us use for the 3 axis skulls. I plan on using my SSC-32 board that I will be using for my 3 axis skulls.


----------



## DarkLore

I'm not expert...but I'm using the picaxe boards for projects requiring a single servo. There's a very limited amount of space for programming on the 08 but my movements are quite basic.

For non 3-axis, speaking/singing skulls I use a cowlacious board with audio coming from an mp3 player.

For a 3 axis movement, I agree with halstaff. I'd look at the ssc-32 or something similar...driven with VSA. To identify servos...check out what others are using by browsing the threads. Graveyardskulls offers 3-axis kits that describe the servos they use for 3-axis movement. Servo city's listings will show speed and torque values to find comparible servos.


----------



## fritz42_male

I'd recommend using the Cowlacious sound to servo board as well (the Scary Terry one) although I'm hoping to come up with my own picaxe based version.

For servos, I get mine off eBay - I'm using the MG995/996. I'm part way through Dave Corr's neck build - it was difficult to find the castor he uses.

http://cgi.ebay.com.au/2-x-MG995-Hi...Radio_Controlled_Vehicles?hash=item27aba89203


----------



## halstaff

I can't wait for the picaxe based sound board! Cowlacious makes a great product but I would love to be able to use the picaxe version.
I got my caster from McMaster-Carr http://www.mcmaster.com/#78155t51/=5qwpx2
It's a 2 inch wheel. I did have to screw the plate on as it doesn't have the clearance to pop rivet.


----------



## Dead Things

I looked up the HiTec HS425BB servo and it has roughly 41 oz-inches at 4.7V. So I should be aiming for that much torque? I found some servos on ebay and think I will get them as they have about the same amount of torque, although they are not HiTec. Hobby Partz has very inexpensive servos, however shipping to get them north of the 49th is as much as the servos. Am looking forward to building that neck mech and messing around with the picaxe 08, although I have no idea what I am doing with it so be prepared for the stoopid questions.


----------



## hpropman

bring on the stoopid questions those are the best kind oh and Fritz I already have a working sound to servo picaxe sound board it you want to see it in action just look at my joking skellies they are each using one. It will be in the book.


----------



## halstaff

Looking forward to the sound to servo picaxe board! I have a board set aside just waiting for the release of the plans.


----------



## halstaff

One other thing if you use the same caster I did for Dave's neck build http://www.mcmaster.com/#78155t51/=5qwpx2 is that the wheel is not removable from the caster. A little harder to work with but no big deal.


----------



## fritz42_male

hpropman said:


> bring on the stoopid questions those are the best kind oh and Fritz I already have a working sound to servo picaxe sound board it you want to see it in action just look at my joking skellies they are each using one. It will be in the book.


Grrrrrrrr!!!!!

Beaten to the punch again!

Any chance of an advance preview of the circuit & board layout? How close are you to finishing?


----------



## fritz42_male

halstaff said:


> One other thing if you use the same caster I did for Dave's neck build http://www.mcmaster.com/#78155t51/=5qwpx2 is that the wheel is not removable from the caster. A little harder to work with but no big deal.


I managed to find the exact one he uses but wasn't using a drill press, slipped, snapped the drill & gashed my hand badly. Think I have an argument for legal action? lol


----------



## halstaff

Sounds like something I would do. I hope you heal up quickly and it doesn't keep you from working on your projects. Maybe it's a hint to work on designing another great picaxe device! 
Where did you find the wheel (although maybe I should stick to the less dangerous one)?


----------



## fritz42_male

All good now but haven't got back to it yet.

Surprisingly, I found it in a national hardware chain (Bunnings). I picked up some rigid plastic ones as well and will try something with those.


----------



## hpropman

fritz42_male said:


> Grrrrrrrr!!!!!
> 
> Beaten to the punch again!
> 
> Any chance of an advance preview of the circuit & board layout? How close are you to finishing?


OK guys I will dig out my notes and draw up the circuits for you. Please try to be patient I have been shoveling snow and everything hurts at the moment.


----------



## fritz42_male

I'd send you some of our weather if I could - gonna hit 37c here on Sunday (98.6F).

Soon melt that snow!


----------



## Dead Things

37C??!! I wish, it was -37C a couple of weeks ago, not bad until you add the 30km wind lol. Anyhoo, haven't recieved my picaxe yet as the snow in the Eastern US has held up shipment. As far as powering these boards and servos, has anyone tried using a cellphone charger? I've got a bunch of these and several are 5VDC.


----------



## hpropman

Make sure that it is 5 volts anything hgher than 5.5 volts will damage the chips. you wll need to measure with a multimeter.


----------



## fritz42_male

Dead on 5V is fine. Current is the issue - servos can draw up to 1 Amp. Better to buy some of the cheap DealExtreme PSP power bricks - less than $5 and free carriage. Rated at 5V, 2A


----------



## Dead Things

fritz42_male said:


> Dead on 5V is fine. Current is the issue - servos can draw up to 1 Amp. Better to buy some of the cheap DealExtreme PSP power bricks - less than $5 and free carriage. Rated at 5V, 2A


I have a Computer power supply that I am going to hack. Would that be the better option?


----------



## fritz42_male

Dead Things said:


> I have a Computer power supply that I am going to hack. Would that be the better option?


Computer PSUs are great - tons of grunt and a nice range of voltages. Trouble is that they need hacking and are quite big. I've posted a thread on a combined 12V and 5V PSU that I found on eBay - 2A per voltage. Universal input voltage and quite small too. Less than $4 each inc postage.

If that's enough for you, try that thread:
http://www.hauntforum.com/showthread.php?t=20378


----------



## hpropman

Either option would work fine it really depends on you and your prop. The computer supply can have the wires extended and placed away from your prop.


----------



## Dead Things

Am waiting for my micro 08 and I ordered 4 servos. I've been doing a bunch of research, reading through this thread and some of the others and am convinced the 08 I purchased will not be able to run the servos, but that's ok, I'm sure I will find a use for it. I think the minimum I could use would be an 08M and even that would be sketchy. I think I'm beginning to get my head around this stuff but I'm still taking baby steps.


----------



## fritz42_male

An 08 will run 4 servos although 3 is a better bet. The limitation is the amount of program space. Coz 08s are so simple and so cheap, I use one per function.


----------



## Dead Things

What kind of power supply do I need to run the servos? If I have 6 servos in one prop (3 axis neck, 2 axis eyes and jaw) and each servo can draw 1 amp, do I need a 6v, 6amp power supply?


----------



## hpropman

Dead Things said:


> What kind of power supply do I need to run the servos? If I have 6 servos in one prop (3 axis neck, 2 axis eyes and jaw) and each servo can draw 1 amp, do I need a 6v, 6amp power supply?


I would just use a PC power supply. The difference between running a servo at 5 volts verses 6 volts can not be seen. otherwise yes a 6 volt power supply with a least 8 to 10 amps. Make sure that it is is a regulated 6 volt supply and more that 6 volts will damage the servos. It will be cheaper to use a PC supply though especially if it is from curby's or if you have an old PC laying around.


----------



## jabberwocky

So are any of these going into "production"?


----------



## hpropman

This is just a modification of an existing Board. However, the Picaxe book is proceeding and I plan to have circuit board files available for download that can be ordered by a group for a make and take. The nice thing about doing it this way is that the more boards you order the cheaper the boards will be. then you just need to have a solder session to assemble the boards. I am planing four controllers at this point based on the 08M, 14M, 20M, and the 20X2. these will be similar to the prop 1 / 2 controllers.


----------



## halstaff

fritz42_male said:


> Phil (pshort) has another thread running also with servo controllers. Have a look here:
> 
> http://www.hauntforum.com/showthread.php?t=17772
> 
> His looks easier to assemble as it is custom designed for servos. Mine is more generic.
> 
> I'll be making a few changes to my controller based on his advice - mainly taking out the 330 ohm resistors. If you want me to rewrite my howto, this will simplify wiring one up greatly!
> 
> I've got more boards on order - once I get them I don't mind posting you a board to try with one of your existing chips. It will be a tested board. The amended version will allow you to run SSR AC relays directly (without any further mods) so you could also use it as a prop timer.


I've got my first Picaxe 08 built and accepting downloads. Are you still planning on changing the controller? I would like to use the updated version if it is available.
Thanks.


----------



## halstaff

fritz42_male said:


> Oh yeah - I forgot - my Alzheimers is bad today! lol
> 
> Anyway, here it is:
> 
> start: symbol counter = b3
> symbol pointer = b2
> symbol delay = 28
> let b2=153 'set pointer offset so that head loop does not get stuck
> let b0=150
> let b1=150 'set default center values
> servo 4,pointer 'center servo
> pause 6000
> 'full motion range test
> for counter = 150 to 120 step -2 'move head from middle to right side
> servo 4,counter
> pause delay
> next counter
> 'servo 4,120
> pause 3000
> 
> for counter = 120 to 180 step 2
> servo 4,counter 'move head from right to left
> pause delay
> next counter
> 'servo 4,180
> pause 3000
> 
> for counter = 180 to 150 step -2
> servo 4,counter 'move head from right to middle
> pause delay
> next counter
> 'servo 4,pointer
> pause 2000
> 
> move: random w0 'place a random number in wo (also B0 & B1)
> 
> if b1<100 then left 'check for random left
> if b1>=100 and b1<=155 then middle 'check for random middle
> if b1>=155 then right 'check for random right
> goto move 'keep moving the head back to move loop
> 
> right: if pointer = 120 then move 'if head is already Right goto back to move
> if pointer = 150 then mr 'check to see if head in pointed middle or the left
> for counter = 180 to 120 step -2 'move head from left side to the right side
> servo 4,counter
> pause delay
> next counter
> pointer = 120 'set head pointer direction to right
> goto skipmr
> 
> mr: for counter = 150 to 120 step -2 'move head from middle to right side
> servo 4,counter
> pause delay
> next counter
> pointer = 120 'set head pointer direction to right
> 
> skipmr: pause 7000 'delay to look natural
> goto move 'return to move loop
> 
> middle: if pointer = 150 then move 'if head is already in the middle then go back to move
> if pointer = 120 then ml 'check to see if head is pointed left or right
> for counter = 180 to 150 step -2
> servo 4,counter 'move head from right to middle
> pause delay
> next counter
> pointer = 150
> goto skipml
> 
> ml: for counter = 120 to 150 step 2
> servo 4,counter 'move servo from left to middle
> pause delay
> next counter
> pointer = 150
> 
> skipml: pause 9000 'delay to look natural
> goto move 'return to move loop
> 
> left: if pointer = 180 then move 'if head is already left then return to move
> if pointer = 120 then lmr 'check if the head is in the middle or the right
> for counter = 150 to 180 step 2
> servo 4,counter 'move head from middle to left
> pause delay
> next counter
> pointer = 180
> goto skiplmr
> 
> lmr: for counter = 120 to 180 step 2
> servo 4,counter 'move head from right to left
> pause delay
> next counter
> pointer = 180
> 
> skiplmr: pause 7000 'delay to look natural
> goto move 'return to move loop


Is it possible to add to, change or condense this code so that you can have random movement on 3 servos and still use an 08?


----------



## fritz42_male

It's hpropman's code and I just used it directly - I believe Darklore may have played with it.


----------



## scream1973

I am very interested in starting down this path to build a small controller to randomly turn a bucky skull from side to side using a servo and also light LED eyes with potentially fade.

What chip would you recommend me to get to do this will the one in the how to suffice?


----------



## hpropman

The 08M or 14M are the best chips to start with. My greeter uses 3 08M's one for the jam movement, one for the fading eyes, and one for the random head movement. at $3 or so a chip it was easy to just drop another one in for what I wanted it to do.


----------



## halstaff

hpropman said:


> The 08M or 14M are the best chips to start with. My greeter uses 3 08M's one for the jam movement, one for the fading eyes, and one for the random head movement. at $3 or so a chip it was easy to just drop another one in for what I wanted it to do.


What do you use to power them all? Are you using individual battery packs or wiring them up to a single wall wart?


----------



## hpropman

Sorry for the delay in replying - I use a 7805 voltage regulator circuit for the electronics and a 7806 circuit for the servos. The reason that there are so many boards is that I have made several changes to him over the last few years and the boards can easily be combined into one. See these videos below they will explain and if you still have questions please ask me.

Halloween 2008 :: Video_0040.flv video by jmalt31 - [email protected]@[email protected]@http://vidmg.photobucket.com/player.swf?file=http://vidmg.photobucket.com/albums/v147/jmalt31/Halloween%202008/[email protected]@[email protected]@[email protected]@[email protected]@[email protected]@[email protected]@v147/jmalt31/Halloween%202008/Video_0040

Halloween 2008 :: Video_0039.flv video by jmalt31 - [email protected]@[email protected]@http://vidmg.photobucket.com/player.swf?file=http://vidmg.photobucket.com/albums/v147/jmalt31/Halloween%202008/[email protected]@[email protected]@[email protected]@[email protected]@[email protected]@[email protected]@v147/jmalt31/Halloween%202008/Video_0039


----------



## scream1973

Ok i have built this board as drawn ( i thnk)

I was able to download a piece of test code to the chip so i think thats good to go..

However i dont seem to be getting anything out of the servo other than when i first plug it onto one of the 3 pin headers and it just moves for a splitsecond


----------



## halstaff

scream1973 said:


> Ok i have built this board as drawn ( i thnk)
> 
> I was able to download a piece of test code to the chip so i think thats good to go..
> 
> However i dont seem to be getting anything out of the servo other than when i first plug it onto one of the 3 pin headers and it just moves for a splitsecond


Do you have a picture of the board? Are you using fresh batteries? Which test code are you using?
I'm sure you'll get the help you need. This is a great little controller!


----------



## fritz42_male

I'm around now as well (got caught with those airline delays due to the volcano). Yup - pictures would be handy.

An easy test method is to use an LED between the signal and ground. (top and bottom pins of each connector) and it should light and flicker faintly if receiving servo commands. You can further test by using high and low commands for that port. Check the (unfinished) document for the board for the code.


----------



## scream1973

I will take some pictures tonight and post them.. My soldering skills are not the best but i managed to get through it and the code downloaded which was a good start.

I used the servo test code from the document. Fresh batteries. I will do a reconnect of the power for the servos as this was just kinda half assed placed into the holes for a quick test.

One thing I did end up using a 10k 1/2 watt resistor instead of 1/4 but not sure if this would matter at all.


----------



## hpropman

Yes we need to see the circuit and the code. Remember that the Pin I/O numbers do not match the actual pin numbers it is easy to forget or you may be on a different I/O pin then the pin the code is talking to. That little movement you are getting is the servo centering itself on power up. Also make sure that all grounds are connected and that the picaxe is getting no more than 5 volts


----------



## scream1973

Code is as follows

BEGIN:
HIGH 0
PAUSE 1000
LOW 0
SERVO 1,75
SERVO 2,75
SERVO 4,75
PAUSE 500
SERVO 1,115
SERVO 2,175
SERVO 4,115
PAUSE 500
GOTO BEGIN

its not pretty but here we go


















Moved the jumper from PROG to OUT after downloading the code.

Top/Bottom pin yeilded no results on any outputs with LED .
I did get the LED to glow on the bottom left by going bottom/middle

Testing with the LED yeilded no real results.


----------



## scream1973

I think i figured it out i had a bad connection between the first set of pin headers (bottom left ) and the next set.. 
I toned it out for conductivity and found none.. I fixed it and now when i put the servo on that port i get the servo moving back and forth.

Nothing with the LED still so i may have hosed that LED i was using


----------



## hpropman

It is hard to see some of the connections and you have a lot of cold solder joints. The first thing I would do is fix all the solder joints. Go to my website and download my picaxe book and read the soldering chapter. remove the chip first. also check to make sure that you do not have a short between the + and GND. Remember the picaxe can not run on more than 5 volts (3 AA alkaline cells or 4 rechargeable cells). also the 22K resistor needs to be closer to the board all of those long leads generate noise which you do not want. check all of your connection paths with your meter and fix any that are not working after you fix the solder joints. I would pick up a proto board from radio shack and practice your soldering is is not hard once you follow the steps. Also I would pick up one of these to fix any soldering mistakes. The best tool that I have ever used to unsolder something.

http://www.radioshack.com/product/index.jsp?productId=2062731


----------



## fritz42_male

I agree with hpropman - looks like some of the joints are a bit iffy. The only thing with these boards is that the tracks lift easily so when I used the tool hpropman linked to, I had issues. I like using desoldering braid for cleaning joints up on boards like this.


----------



## scream1973

would something like this be a better choice then ? http://www.radioshack.com/product/index.jsp?productId=2062745


----------



## fritz42_male

Effectively the same thing. Using a solder sucker requires you to be quite quick and position quite accurately. The board also needs to be held firmly.

Desoldering braid 'wicks' up wet solder quite quickly and I've found it better for boards that have a tendency to lift tracks.

http://www.radioshack.com/product/index.jsp?productId=2062744

If you do mess up a board then it's no big loss as the boards are so cheap and you can transfer the Picaxe chip over.


----------



## scream1973

i cleaned up the first board and built a second one last night.. I think for the first one i was overly concerned about lifting the trace and didnt apply enough heat to get a proper joint but the second one looks a lot better and i soldered in the jumper wires before i put the pin headers in and that made it alot easier for me to get them in place with my big fingers.

With the code and a 5 volt wallwart powering the servo it moved as i would expect it to. Now i just need to get the fading LEDS together and code and also the random movement code onto the chip and start building the reaper


----------



## hpropman

I have used all three methods and the all work if you use them the correct way. I have never used this board so I was unaware of the trace lifting issue. The braid will be the best choice in this case because it acts like a heat sink and draws heat away from the board. One other thing what is the wattage of your iron? For boards like this you might be better off with a 15 to 25 watt iron.


----------



## scream1973

My iron is a variable wattage one kinda like the one in your book. I use it on about 3/4 setting


----------



## fritz42_male

Good progress.

I find a high heat fine tip soldering iron is actually better for this kind of work as you are quick on and quick off on a join.

I use a DSE (RadioShack) variable power soldering station - equivalent to a Weller station but cheaper.


----------



## scream1973

any further developments on this ?


I have to play with the extents for the servos to get the range i am looking for as right now it looks to be around 90 degrees total


----------



## JeffHaas

I just got my first batch of 08Ms in from Peter Anderson. Put together a download cable and made my first VLC controller tonight.

One thing the doc could really use - a diagram that labels everything on a completed board! Plus what you can use each of the connections for (servo, LED, PIR, etc.) I can figure it out but it would be easier with a picture! Also it would help me to label the board itself when completed, with little stickers like people make for the Picaxes.

Oh, and did you notice that the last section (Analogue Input Testing) is missing the code?

Overall, thanks for this project! Looking forward to lots of stuff with it.

Jeff


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## fritz42_male

I'll try and get round to finishing it soon. I'm also adding some daughter boards for other functions.

Also there is now an 08m2 which makes it feasible to have the Vlc run 4 programs simultaneously.

One of the main points of the vlc is the 3 pin connector as it supplies power and ground to the add ons as well as signal in/out.


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## JeffHaas

If you need someone to proofread it, I'm happy to help. I've done this for several other small technical publications. And I happen to be at the right point to help - just learning Picaxe but I know how to solder and other basic hobby electronics skills.


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## fritz42_male

Thanks for the offer. I hope to get stuck back into it soon.


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