Search found 23 matches

by kcoelho
Thu Nov 14, 2019 3:09 pm
Forum: General Discussion and Questions
Topic: CAN on STM32F4xx
Replies: 12
Views: 1382

Re: CAN on STM32F4xx

Do you have a Pyboard or any Nucleo or Discovery board with dual CAN MCU. It might be worth trying your hardware and test script on other hardware. I think I managed to fix it. The problem seems to go away after I initialize the Standby pins on each of the transceivers and then do a board reset. No...
by kcoelho
Wed Nov 13, 2019 2:16 pm
Forum: General Discussion and Questions
Topic: CAN on STM32F4xx
Replies: 12
Views: 1382

Re: CAN on STM32F4xx

I used a similar CN transceiver from Microchip. Yours needs dual supplies and enable, mine had slope control. Shouldn't make any difference as long as all 8 pins are connected. I presume you are using STM32F439 port as a starting point for your board. Are you using the same pins as specified in mpc...
by kcoelho
Tue Nov 12, 2019 4:59 pm
Forum: General Discussion and Questions
Topic: CAN on STM32F4xx
Replies: 12
Views: 1382

Re: CAN on STM32F4xx

I have used that test script on several Nucleo boards. What board and MicroPython version are you using? If it's custom post your mpconfigport.h What CAN transceivers are you using? Are they powered from 3.3V or 5V? What is the logic 1 input threshold on the MCU side? TTL compatible parts are 2 to ...
by kcoelho
Mon Nov 11, 2019 7:30 pm
Forum: General Discussion and Questions
Topic: CAN on STM32F4xx
Replies: 12
Views: 1382

Re: CAN on STM32F4xx

Do you have a termination resistor on the CANbus? CAN tranceivers are open collector and won't work without a termination resistor to define the recessive state. If you just connect two tranceivers together without a bus a single 50 to 100 ohm resistor should work. Here is the test script I used to...
by kcoelho
Mon Nov 11, 2019 6:52 pm
Forum: General Discussion and Questions
Topic: CAN on STM32F4xx
Replies: 12
Views: 1382

Re: CAN on STM32F4xx

I'll start with the obvious. You will need to post more detail with regards to type of transceivers, wiring of the CAN bus and the micropython code use are using that demonstrates the problem. Without this information it is difficult to speculate on what the problem may be. :) The chip has the buil...
by kcoelho
Fri Nov 08, 2019 7:23 pm
Forum: General Discussion and Questions
Topic: CAN on STM32F4xx
Replies: 12
Views: 1382

CAN on STM32F4xx

Hello,

Has anyone succeeded in communicating between CAN1 and CAN2 using Micropython on an STM32F4?

Using 2 separate transceivers for each and using jumpers to connect them together. It should allow me to communicate back and forth but nothing works

Anyone have any thoughts?

Thanks
by kcoelho
Fri Nov 01, 2019 6:14 pm
Forum: General Discussion and Questions
Topic: network LAN
Replies: 0
Views: 1278

network LAN

Hello all, I am having trouble with using LAN. The function is available to me when using the REPL prompt and the network library. However, when I call the function, my REPL shuts down and restarts. Using a custom board with the LAN8720 chip, which is the same as on other STM32 boards that have work...
by kcoelho
Thu Sep 19, 2019 2:19 pm
Forum: General Discussion and Questions
Topic: UART issues
Replies: 4
Views: 492

Re: UART issues

And that macro only seems to be used in uart.c in the /stm32 directory Yes, everything in the machine is implemented per-port (with some common code extractes out for things like SPI and I2C) But yes, uart.c uses those macros to map the uart number passed to the constructor, so you'll need to add t...
by kcoelho
Thu Sep 19, 2019 1:29 pm
Forum: General Discussion and Questions
Topic: UART issues
Replies: 4
Views: 492

Re: UART issues

hi, If you grep the codebase for where (for example) MICROPY_HW_UART6_TX gets used and you'll see the code that actually uses these macros. What baud rate are you setting it to when you get that error? I'm setting it to 9600 And that macro only seems to be used in uart.c in the /stm32 directory
by kcoelho
Wed Sep 18, 2019 7:04 pm
Forum: General Discussion and Questions
Topic: UART issues
Replies: 4
Views: 492

UART issues

Hello, I have a custom port for the stm32f437 MCU and I have been trying to get UART7 and UART8 working but I cannot get it working. I have added the definitions to the mpconfigboard.h #define MICROPY_HW_UART7_TX (pin_E8) #define MICROPY_HW_UART7_RX (pin_E7) #define MICROPY_HW_UART8_TX (pin_E1) #def...