uno32 with MCP2515

Created Fri, 01 Apr 2016 19:29:56 +0000 by gromgsxr

gromgsxr

Fri, 01 Apr 2016 19:29:56 +0000

i am using a cheap can module: http://www.ebay.co.uk/itm/Arduino-MCP2515-CAN-Bus-Module-TJA1050-Receiver-SPI-Module-UK-seller-/301867609139?hash=item4648b62c33:g:YDIAAOSwKIpV~w8n just like this one on a uno32 using the seeedstudio library that can be found here: https://github.com/Seeed-Studio/CAN_BUS_Shield , and all is working well i'm using an interrupt on pin2 (int1) "attachInterrupt(1, MCP2515_ISR, FALLING);"

it all works fairly well the uno can send and receive data over the can bus from the car ecu, and display data on a screen, but there is one annoying problem the uno has to be powered up first before the ecu otherwise it will just sit there doing nothing its like the interrupt is not firing. but if the uno is powered up first and then the ecu it all works as expected.

im looking for ideas as to what may be the problem?

guymc

Tue, 05 Apr 2016 17:10:23 +0000

Hi, I'm very interested in this project and will try to help. Contacting you offline now...

gromgsxr

Thu, 07 Apr 2016 00:59:30 +0000

well it appears its possibly an issue with the library as i got the exact same behaviour when i tested with an arduino uno and a arduino mega, so its not just a chipkit thing.