Search found 8 matches

by folke
Sun Aug 28, 2016 5:46 am
Forum: MicroPython pyboard
Topic: connecting pyboard to CAN BUS
Replies: 45
Views: 18003

Re: connecting pyboard to CAN BUS

Hi,

I used a MCP2562 transceiver that has separate pins for logic supply and bus supply, so it fits any controller using 1.8–5.5V.
It's available in PDIP and SOIC.

Greetings
Folke
by folke
Mon Jun 06, 2016 5:54 am
Forum: General Discussion and Questions
Topic: Can I use the can.recv(0) in the rxcallback function?
Replies: 10
Views: 4056

Re: Can I use the can.recv(0) in the rxcallback function?

Hi,

If you haven't done so already, I suggest you study http://docs.micropython.org/en/latest/p ... rules.html to see if that can help you get things working.

I think soft irq will come, but work on it is not finished yet.

Cheers!
by folke
Tue May 24, 2016 4:18 am
Forum: General Discussion and Questions
Topic: CAN Bus Communication
Replies: 12
Views: 6331

Re: CAN Bus Communication

Hi satya369, my code snippet was from my very first experience with CAN, and I actually do not have access to the CAN hardware anymore. So I have not tested with your code. My code was nearly identical to your last shown. I had a logic analyzer hooked up to the CAN transceiver (MCP 2562) and I remem...
by folke
Mon May 23, 2016 4:02 pm
Forum: General Discussion and Questions
Topic: CAN Bus Communication
Replies: 12
Views: 6331

Re: CAN Bus Communication

Hi, This works for me for a CAN bus at 250 kbps with extended frame: ''' Init for 250 kbps <=> bit time 4 µs. If 42 MHz clk is prescaled by 21, we get 8 subparts 'tq' of a bit time from theese parts (# tq): sync(1) + bs1(5) + bs2(2) = 8 * tq = 4µs => 250 kbps''' can.init(can.NORMAL, extframe=True, p...
by folke
Fri Feb 12, 2016 4:33 pm
Forum: General Discussion and Questions
Topic: Optimising Python speed tutorial
Replies: 7
Views: 3047

Re: Optimising Python speed tutorial

Well, I can only second this. I have really missed this kind of good documentation. So I feel a little uneasy to mention one small correction: Time is measured in seconds and the SI-unit is spelled with lower case "s" . (The upper case "S" is used for Siemens [= 1/ohm]). So in the Python code exampl...
by folke
Thu Jan 14, 2016 6:55 pm
Forum: General Discussion and Questions
Topic: random uart.write oserror 116
Replies: 19
Views: 10147

Re: random uart.write oserror 116

Hi again, Yes, Spotlight in Mac OS X is indexing the SD card (which in my case contains ≈100 files). These accesses clearly disturbs the UART Tx (and also Rx), see the second picture in my first post, where the blue Dbg trace shows that it nearly takes 1s to send the 24 chars because they get split ...
by folke
Sun Jan 10, 2016 7:57 am
Forum: General Discussion and Questions
Topic: random uart.write oserror 116
Replies: 19
Views: 10147

Re: random uart.write oserror 116

Thank you Dave, You give clear facts as usual, and I realize now I have some homework to do. Yes, USB mass storage was enabled and maybe Spotlight is playing some tricks on the SD card, that I didn't think about. So an easy test is to disconnect the USB to the Mac and see if problem disappears. I'll...
by folke
Sat Jan 09, 2016 10:14 pm
Forum: General Discussion and Questions
Topic: random uart.write oserror 116
Replies: 19
Views: 10147

Re: random uart.write oserror 116

Hi all, I too have problem with getting occasional oserror 116 when doing simple uart writes. In my case it's on pyboard v1.0 and the two latest firmwares 1.5.1 and 1.5.2. I have caught some occasions on a logic analyzer and have realized that while sending string at 9600 baud (no handshaking) there...