pololu motor problems, getting no action. BS2, pololu micro dual serial contro
I am using a bs2, and a Pololu Micro Dual Serial Controller
This is really a little ahead of me, but this is the first time I have hooked up something and it just gets nothing.· Nada.
I have tested the motors, and just been through all the threads here under "Pololu" search.
http://www.parallax.com/detail.asp?product_id=30052
I believe I have it wired correctly, as in two motor documentation with Pololu. Seperate· 9v driving the motors &·9V on logic board, common ground.
This is my first time hooking up the controller, but I have checked and double checked.· No heat, no nothing.· No motors.
The motors do turn if wired directly.
The·code, taken from the nuts and volts article....
I appreciate anyone who can help me.· Thanks!!!
Post Edited (neoteric) : 2/12/2006 12:34:14 PM GMT
This is really a little ahead of me, but this is the first time I have hooked up something and it just gets nothing.· Nada.
I have tested the motors, and just been through all the threads here under "Pololu" search.
http://www.parallax.com/detail.asp?product_id=30052
I believe I have it wired correctly, as in two motor documentation with Pololu. Seperate· 9v driving the motors &·9V on logic board, common ground.
This is my first time hooking up the controller, but I have checked and double checked.· No heat, no nothing.· No motors.
The motors do turn if wired directly.
The·code, taken from the nuts and volts article....
' {$STAMP BS2}
' {$PBASIC 2.5}
MLFwd VAR Word 'l forward'
MRFwd VAR Word 'r forward'
Sout VAR Word 'serial line
Reset VAR Word 'reset line
MLFwd = %11
MRFwd = %00
Sout = 1 'pin 4 on Pololu motor controller
Reset = 2 'pin 5 on Pololu motor controller
Main:
HIGH SOut
DEBUG "reset"
GOSUB Reset_SMC
DEBUG "accel"
GOSUB Accelerate
DEBUG "begin again...."
GOTO Main
Accelerate:
SEROUT SOut, $84, [noparse][[/noparse]$80, 0, MLFwd, 127]
SEROUT SOut, $84, [noparse][[/noparse]$80, 0, MRFwd, 127]
PAUSE 50
RETURN
Reset_SMC:
LOW Reset
PAUSE 100
HIGH Reset
RETURN
I appreciate anyone who can help me.· Thanks!!!
Post Edited (neoteric) : 2/12/2006 12:34:14 PM GMT
Comments
The PBASIC statement which follow, and the comments on them don't match:
Sout = 1 'pin 4 on P controller
Reset = 2 'pin 5 on P controller
The comments imply you're using Pin Ports 4, and 5 but Pin Ports 1 and 2 are being assigned. Which is correct? I'm also not clear on why they're being assigned as WORD variables? Something gives me the impression that the code listed did not come directly from a Nuts and Volts article, that it's been substantially modified.
Regards,
Bruce Bates
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Thanks for helping.· Sorry, the comments should have been clearer...
a case where the comments added confusion as oppossed to clarity.· "P controller" meant Pololu controller.· As for the Word var, is·it OK to use that in this case?· For proto-code?
As for the nuts and volts article, I cut out everything that I believe I ddint need.· I had to add some, as the entire program is not included in the article.· I tried using everthing in the article, first, with the addition of variables.·· When I get back to the board, I will change the Vars, as per your suggestion.· (I HAVE EDITED THE ORIGINAL CODE IN THE FIRST MESSAGE FOR CLARITY)
The word length variables are causing you a problem. They should really all be constants. Try:
MLFwd con 3 'l forward
MRFwd con 0 'r forward
Sout con 1 'serial line pin 4 on Pololu motor controller
Reset con 2 'reset line pin 5 on Pololu motor controller
Then call the reset subroutine before the "Main:" loop, not within the loop.
Finally, take the "$" off of your Baudmode. 84 should be a decimal. When you type $84 you are making it a hex number which is actually 132 decimal.
I think that these changes should make it work. Try it again and post your results.
Rick Brooks
Brooksbots.com
There is a working example BASIC Stamp II Program that is in the Pololu documentation.
SPEED···var··byte
RESET_DSMC··con··15
output 14
DEBUG CLS
DEBUG "Reset Controller", CR
Low RESET_DSMC
pause 10
High RESET_DSMC
DEBUG "Ramp Up Motors Forward", CR
for SPEED = 0 to 127
·· serout 14,32,[noparse][[/noparse]$80,0,1,SPEED]
·· pause 50
·· serout 14,32,[noparse][[/noparse]$80,0,3,SPEED]
next
pause 1000
DEBUG "Ramp Down Motors Forward", CR
for SPEED = 127 to 0
·serout 14,32,[noparse][[/noparse]$80,0,1,SPEED]
· pause 50
· serout 14,32,[noparse][[/noparse]$80,0,3,SPEED]
next
pause 4000
DEBUG "Ramp Up Motors Reverse", CR
for SPEED = 0 to 127
· serout 14,32,[noparse][[/noparse]$80,0,0,SPEED]
· pause 50
· serout 14,32,[noparse][[/noparse]$80,0,2,SPEED]
next
pause 1000
DEBUG "Ramp Down Motors Reverse", CR
for SPEED = 127 to 0
·serout 14,32,[noparse][[/noparse]$80,0,0,SPEED]
· pause 50
· serout 14,32,[noparse][[/noparse]$80,0,2,SPEED]
next
end
Thats what I get for working on it so late. I actually wired it from scratch 3 times last night, and missed that connection all 3 times!
Wired correctly, the first program I posted does run, although it does reset everytime. Moved the reset out of the main loop as suggested by Rick.
Bruce, just learning about variables. Sure enough, I have not written a program yet that struggles for memory. But as of today, I am paying attention to variable usage. For some strange reason, I just didnt understand that variable types actually take up space differently, but I got that concept now... Thanks.
Steve, I will review your program, and try it. BTW, I simply cannot find that documentation! Not on thier site, definitely not with the controller. AM I CRAZY? I am one of those persons who does the research before asking.... In fact, lots of research. Probably too much, as my retention is not so good some times....
One other question: It does not seem to matter whether I use $84 or 84. Which now has me very confused. Because what you said about that, Steve, does make sense. Although the NV article has it as $84. Is this because the original article was written for a BS1? Just trying to learn here...
Once again, I cannot thank you folks enough for helping me. I have done tons of experimentation, and purchased 4 different learning packages from Parallax and been through each. I will probably have more questions, as this robot I intend to make a little more complex. (I want to add an arm....)
Thanks! I only hope I can get good enough to help others!
There is a difference between a baudrate of 84 and $84, but you probably won't notice.
The Pololu takes any baudrate from 1200 to 19,200.
When you use a baudrate of 84, the data is sent at 9600 bits per second. When you use a baudrate of $84, in decimal that is 132 which results in about 6579 bits per second.
Just don't try to change baudrate in the middle of a program. The Pololu "locks" onto the first rate that it sees after a reset and will use that rate until another reset.
Rick Brooks