Question on CAN wiring
Posted: Wed Dec 27, 2017 5:53 pm
I have a MS2/v3.0 that I didn't build. It's driving a Toyota 4AGE and there is an RX7 daughterboard (I am not sure what that does) and there's some stuff on the proto area (looks like a relay control circuit I think - not 100% sure)..
My issue is that this proto circuit connects to SPR1(CANH). I presume this is just to break it out to the DB37 but again - not sure and I haven't traced that wire in the loom yet. I also haven't checked to see where it comes from on the board so I could look at that in the config. (yet)
Note that JS6 and JS8 have nothing connected to them.
Am I right in assuming that SPR1 and SPR2 (CANH/CANL) are only named that way for convenience, and that unless connected to JS6/8 they have no special use at all except as a path to the DB37 pins 3 and 4?
Given SPR1 is used, and JS6/8 are not used at all, could I simply take JS6 and 8 to a new 2 pin connector and use that as my CAN bus connector? (and leave SPR1 doing whatever it's doing right now?)
This all seems reasonable to me but I have read the docs and thought I would make sure. I have found in the MSGPIO docs this description...
Which seems to indicate that I could intercept before SPR1/SPR2.
Cheers - Neil "Got the soldering iron on standby waiting for confirmation" Gardner
My issue is that this proto circuit connects to SPR1(CANH). I presume this is just to break it out to the DB37 but again - not sure and I haven't traced that wire in the loom yet. I also haven't checked to see where it comes from on the board so I could look at that in the config. (yet)
Note that JS6 and JS8 have nothing connected to them.
Am I right in assuming that SPR1 and SPR2 (CANH/CANL) are only named that way for convenience, and that unless connected to JS6/8 they have no special use at all except as a path to the DB37 pins 3 and 4?
Given SPR1 is used, and JS6/8 are not used at all, could I simply take JS6 and 8 to a new 2 pin connector and use that as my CAN bus connector? (and leave SPR1 doing whatever it's doing right now?)
This all seems reasonable to me but I have read the docs and thought I would make sure. I have found in the MSGPIO docs this description...
Code: Select all
On MS-II™ controllers, the CANbus circuits are:
CANH: CPU pin PM0 (#45) → 40-pin socket pin 6 → JS6 jumper to SPR1/CANH → DB37 pin 3,
CANL: CPU pin PM1 (#44) → 40-pin socket pin 11 → JS8 jumper to SPR2/CANL → DB37 pin 4.Cheers - Neil "Got the soldering iron on standby waiting for confirmation" Gardner