Hello everyone,
Im almost done with a robot i was making from scratch ( a quadruped ), got all the parts cut and the electronics ordered !. Yesterday, i was making a program that simply centers all the servos. Im using Bot Board 2 and basic atom pro 28 powered by [6.0 Volt Ni-MH 2800mAh Battery Pack](http://www.lynxmotion.com/p-426-60-volt-ni-mh-2800mah-battery-pack.aspx), things are all set and ready to go!.
I turned on the switch, the program starts, but the servos never budge.They make a buzzing sound as if they're stuck but i can freely move them by hand as if they were unpowered. I thought at 1st the body was too heavy on them so i lifted it up but still nothing so far,i also used 9v battery but still. Here is the code im using :
[code]pause 1000
main
hservo[0\127,1\127,2\127,3\127,4\127,5\127,6\127,7\127,8\127,9\127,10\127,11\127]
goto main[/code]
The servos use pins from p0 to p11 while ps2 receiver has the pins p12 to p15 , the servos are Hitec 255bb mighty mini servos, 16 of them ( 12 working and 4 of them ill connect to 1 pin later as they move together in the same time ).
Thanks for help and the wonderful forums 
Can you post an image of your wiring?
sorry that the wires look kinda messy since im not focusing on the looks now, here it is:
truploader.com/uploads/1_24_ … .10.53.jpg
Yeah that helps… Two things.
Your battery wiring harness has wires frayed at the connector. Please go back and carefully make sure there are no wires sticking out. The way it is now, it could short out and the battery would heat up!
The jumpers above the IO pins set the voltage the servos receive. They can be set for 5vdc or the raw servo voltage. When you’re powering servos you need to use VS as the 5vdc regulator on board will not be able to supply the required current. I hope the regulator is not damaged already.
Thanks for your reply, im done fixing the wire harness and changed the jumpers above the IO pins to vs. Fortunatly the regulator is fine but still the servos arent moving. I removed the vs=vl connector and add 9v to VL and the battery pack to servos only (VS), and the results were better, but still having a problem, 2 legs seem to operate almost at full power while the other two are still dead. im checking my wire connections at the moment to see if something is wrong.
Waiting for your response.
Edit: the buzzing sound can still be heared even though the servo power is off, i think its the speaker.
Make sure you moved all jumpers for the banks that have servos connected.
Is the 6vdc battery fully charged?
There is a buzzing sound coming from where? Maybe it’s time for a video?
Is this a beeping sound? What program are you running?
All jumpers are connected to vs, the battety 1st use was today and the buzzing sound was coming from the speaker, i simply removed its jumper connector, now its gone . the unpowered servo problem remains.
Edit: After removing the speaker, some servos that weren’t working are working now, seems like a current problem
pin 9 is the speaker pin, and the program sends pulses to the servo at pin 9 so i think it was sending pulses to the speaker. it would be beeping if it wasnt pulses i guess, im still using the same program.
Ok, yes the speaker is on pin 9 and it is clicking with the servo pulses.
There should be no way for the speaker enable jumper to effect the servo pulses. It’s not connecting a speaker, but connecting a high impedance input to a low impedance output IO pin.
Do you have the legs supporting the weight of the robot, or is the bot suspended off the ground? Could we get an image of the bot to look for hardware problems? Are you connecting the servos directly, or are you using servo extenders?
Also do you have a volt ohm meter? Can you check the voltage from the 5vdc regulator to ensure it’s providing the full 5vdc?
i have one, checking now
Edit: yea, its delivering 5vdc
When you edit I do not know and it’s slowing things down…
You neglected to address these…
Do you have the legs supporting the weight of the robot, or is the bot suspended off the ground? Could we get an image of the bot to look for hardware problems? Are you connecting the servos directly, or are you using servo extenders?
Sorry for just turning up out of nowhere but I might have a suggestion (although I’m not sure if it’ll work). I saw the code:
[code]pause 1000
main
hservo[0\127,1\127,2\127,3\127,4\127,5\127,6\127,7\127,8\127,9\127,10\127,11\127]
goto main[/code]
And if I remember correctly, the hservo command in the Basic Micro Studio Manual uses the following:
[code] main
hservo [p0\0\500, p1\0\500]
goto main[/code]
Would it be necessary to have the servo angle (i.e. the bold part of this - p0*0*\500) for the code to work? If so, then that might explain why the servo horns can be moved freely.
The format is pin, position, speed. So if the speed is not there it will move as fast as possible. I don’t think that’s it, but there is something missing… enablehservo might help… 
enablehservo
hservo [0\0\0]
start:
goto start
I’m pretty sure it works without the ENABLEHSERVO command because I made my robot walk without having it - I just set up the values with the hservo command and off it went.
Hmm, last time i checked the enableservo command is not needed anymore as the servos will be enabled when needed. about your previous questions, the servos are directly connected. So far only 3 legs are working (all for legs are identical) and they’re slowly collapsing under the body weight… maybe i should make another design lighter than this alumnium.
I took some pictures but they’re very big for some reason, im fixing the size in photoshop then ill post them here.
Also, I took a look at the photo of the BB2 and does it matter which pins the jumpers are on? The picture of the BB2 for the BRAT tutorial shows them on the two pins to the left and in the photo of the board, the jumpers are on the right two pins.
that one is an old picture, i already changed those.
Here are the pictures, still not painted, things look a little messy with the wires but nothing is tangled or short-circuiting thats for sure.
truploader.com/uploads/1_24_ … .13.42.jpg
truploader.com/uploads/1_24_ … .16.39.jpg
You’ve probably already tried this but have you attempted to move the servos on their own (i.e. when they aren’t attached to the robot brackets)? Also, the robot does look cool! :mrgreen:
Thanks, just see what ill do with it when its 100% done xD. and yep, i tested all servos before attaching them.
Also i tried changing my code to look like yours, still no change, only 3limbs are working, and all furthermost are off, no way the the legs can handle the weight with only 3 servos lifting. Im still messing around trying to solve this.
