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1. 

   crenn
   Moderator

   While I writing code for my robot today, I came across what I think is a bug, but I can't 100% confirm yet. I forgot to measure if there was any output on the pin, however, this is the code I've tested with. If I compile the same code in v0.0.8, I get the expected result (which is the servo moving).

   http://www.crennsmind.com/Code/Maple/Servo/Servo_Control.txt
   http://www.crennsmind.com/Code/Maple/Servo/Servo_Test.txt

   Posted 4 years ago #
2. 

   crenn
   Moderator

   Since I had to go back to my university briefly today, I hooked up at DSO to the Maple to take a look at the output of the pin, these are the traces.

   v0.0.8
   http://www.crennsmind.com/Code/Maple/Servo/DSO/v0.0.8/Signal-Wave.BMP
   http://www.crennsmind.com/Code/Maple/Servo/DSO/v0.0.8/Signal-Single_Pulse.BMP

   v0.0.9
   http://www.crennsmind.com/Code/Maple/Servo/DSO/v0.0.9/Signal-Wave.BMP

   v0.0.snapshot110213
   http://www.crennsmind.com/Code/Maple/Servo/DSO/v0.0.snapshot110213/Signal-Wave.BMP

   There was no output in the last 2, but in v0.0.8 you can see it's working normally. Sorry about the small size of the traces, it's unfortunately how the DSO outputs.

   Posted 4 years ago #
3. 

   jumpnowdev
   Member

   I just got my board and I'm using Maple IDE 0.0.9. PWM is working for me at least on the pins I tried. It's the first thing I attempted after SerialUSB and regular Serial TTL (to a Gumstix). I tested PWM output with timers 1.1, 2.4, and 3.1.

   I can provide the code or oscope screenshots if needed.

   Posted 4 years ago #
4. 

   crenn
   Moderator

   That is the one thing I didn't try, which was different timers/pins. I'll see if it's working for me on 1.1 tomorrow.

   Posted 4 years ago #
5. 

   Darth Maker
   Member

   I'll point you to this thread, where I had the same problem.

   http://forums.leaflabs.com/topic.php?id=611

   For some reason Timer4 doesn't get initialized properly, so you just add that code in.

   Posted 4 years ago #
6. 

   crenn
   Moderator

   Thanks for the link Darth Maker, it now works fine as I would have thought and didn't see that you had the bug (I generally am on the forums reading every day). I'd still label this a bug, as the intended behaviour at initialisation, is that all timers are set to TIMER_PWM ( http://leaflabs.com/docs/lang/api/hardwaretimer.html ), but at least it's a bug with a workaround.

   I added this above Timer4.setPrescaleFactor(PRESCALE); in my code:

   Timer4.setChannelMode(4,TIMER_PWM);

   EDIT: I tested a few other pins, and didn't need the 'work around' but I'm happy enough just using pin 24 with the 'work around'

   Posted 4 years ago #
7. 

   StephenFromNYC
   Moderator

   Hello-

   crenn, in your above post the forum software does not know the closing parenthesis is not part of the URL, so your link is broken.

   If I want to put a URL inside a pair of parentheses I have two solutions:

   Put a space before and after the parenthesis:

   TIMER_PWM ( http://leaflabs.com/docs/lang/api/hardwaretimer.html )

   Or if you do not like the extra spaces you can always explicitly code the link yourself using the "A" HTML markup tag:

   TIMER_PWM (http://leaflabs.com/docs/lang/api/hardwaretimer.html)

   Thanks!

   Stephen from NYC

   Posted 4 years ago #
8. 

   crenn
   Moderator

   I've fixed up the link so it should work normally now.

   Posted 4 years ago #
9. 

   mbolivar
   LeafLabs

   crenn,

   Thanks for the report! I noticed the same behavior on pin 24 a couple of weeks ago; it was a simple PIN_MAP bug. The fix is currently in master; it'll be part of the next release:

   https://github.com/leaflabs/libmaple/commit/b4c2d4514c6d52cac8a649c5d5c24b68a3c0a416#L12L137

   Posted 4 years ago #
10. 

    crenn
    Moderator

    For now, to prevent me forgetting the bug, I've implemented it in the snapshot from Feb.

    Posted 4 years ago #

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