Search found 605 matches

by EmbeddedMan
Mon Oct 31, 2011 11:55 pm
Forum: IDE Integration
Topic: Uno32: microseconds timer glitch every 107.4 seconds?
Replies: 14
Views: 5776

Re: Uno32: microseconds timer glitch every 107.4 seconds?

Does your new version have any glitches like the old version did?
by EmbeddedMan
Mon Oct 31, 2011 3:22 am
Forum: IDE Integration
Topic: Uno32: microseconds timer glitch every 107.4 seconds?
Replies: 14
Views: 5776

Re: Uno32: microseconds timer glitch every 107.4 seconds?

Yes, the core timer fires every 1ms, and is used to keep track of the the milliseconds. And it works quite well, as you've found. The microsecond value, is determined by grabbing the current value of the core timer counter itself, and compensating for overflows and such. That compensation is handled...
by EmbeddedMan
Sun Oct 23, 2011 11:37 pm
Forum: IDE Integration
Topic: comparing I/O speeds with Arduino
Replies: 12
Views: 6960

Re: comparing I/O speeds with Arduino

The core timer interrupt (normally) fires once every millisecond, and it takes very little time (<1uS I think) to execute. If it does slow down the I/O, you would just see a little delay once every millisecond.

*Brian
by EmbeddedMan
Mon Oct 03, 2011 1:39 am
Forum: General Discussion
Topic: proper A4988 stepper motor driver delay sequence ??
Replies: 2
Views: 1807

Re: proper A4988 stepper motor driver delay sequence ??

I've done a lot of work with steppers on many platforms, including designing the Easy Driver and Big Easy Driver (the later of which is an A4988 based breadkout board that SparkFun now sells). I've seen the same things you've seen. For the STEP input on these drivers, it doesn't matter as long as yo...
by EmbeddedMan
Wed Sep 28, 2011 7:28 pm
Forum: IDE Integration
Topic: USB Bootloader
Replies: 2
Views: 1043

Re: USB Bootloader

Yes, there is. We use it on the CUI32 and UBW32 boards - it works for ANY USB enabled PIC32. And it works great with MPIDE. Search this forum for CUI32 and/or UBW32 to find the links to the bootloader.

*Brian
by EmbeddedMan
Sat Sep 03, 2011 7:25 pm
Forum: General Discussion
Topic: Help Needed , UNO32 with self Programed GUI ?
Replies: 3
Views: 1134

Re: Help Needed , UNO32 with self Programed GUI ?

Kyle, Yes, sort of. :-) There is no build-in command parser on the PIC32 side, so you'll need to write that part yourself, to accept bytes over the serial (USB) port and parse them and figure out what to do with them, and then send back results to the PC. There is already some simple stepper code th...
by EmbeddedMan
Sat Sep 03, 2011 5:12 pm
Forum: General Discussion
Topic: Help Needed , UNO32 with self Programed GUI ?
Replies: 3
Views: 1134

Re: Help Needed , UNO32 with self Programed GUI ?

Kyle, As the designer of the Big Easy Driver, I know that your system will work. The trick, as usual, is in the software. To talk to the ChipKIT, you need to open up the COM port that the ChipKIT creates when you plug in. If you use some serial print commands in your code, then you will be able to s...
by EmbeddedMan
Mon Aug 22, 2011 3:44 pm
Forum: Libraries
Topic: Need testers for SoftPWMServo library
Replies: 55
Views: 15462

Re: Need testers for SoftPWMServo library

New version ready: I've released version 1.1 of the SoftPWMServo library. The main change was the fixing of the bug reported above. You can download the new library from here : http://www.schmalzhaus.com/UBW32/SoftPWMServo_v1_1.zip If you are just updating the library, you only need to copy the new ...
by EmbeddedMan
Sun Aug 21, 2011 4:54 pm
Forum: Libraries
Topic: Need testers for SoftPWMServo library
Replies: 55
Views: 15462

Re: Need testers for SoftPWMServo library

OK, I've reproduced the bug. I think it happens every 107 seconds when the Core Timer oveflows from 0xFFFFFFFF to 0x00000000.

I'm now adding code to handle this situation, and will provide an updated library shortly.

*Brian
by EmbeddedMan
Fri Aug 19, 2011 8:22 pm
Forum: Libraries
Topic: Need testers for SoftPWMServo library
Replies: 55
Views: 15462

Re: Need testers for SoftPWMServo library

Ok, good. That's the kind of feedback I'm looking for.

Can you post the simplest sketch that exhibits the problem? Does it change if you have more or less pins enabled? Does it only happen with certain servo pulse durations?

Thanks!!

*Brian