CAN controllers on STMP157-OLinuXino

[dry]

Hello Olimex, Interested in this board,

https://www.olimex.com/Products/OLinuXino/STMP1/STMP157-OLinuXino-LIME2/open-source-hardwarea

 - The chip if I'm not mistaken has 2 x CAN FD on it, are the second CAN controller pins available to connect external transceiver through board's GPIO's blocks, and Linux driver(s) can use second controller? I need to connect own external transceiver(s). If it requires alt function or muxing, what would I loose if I want second CAN, considering the stack thats running on it?

 - Could you confirm that both those CAN controllers and driver supports the hardware timestmaping of messages? (i.e., its not the host's own timestamp)

 - Could you explain the purpose of this 5v/3v3 switch on CAN transceiver on board, doenst' that module only support 5v CAN?

Is there a box/housing available for the board, similar to how you have for A20 Micro?

[LubOlimex]

- About the jumper, it is there for compatibility reasons. If we decide to put other CAN controller. It makes no sense to change it with the CAN controller that we currently use (since it is 5V only), but we have used controllers in the past that could work at 3.3V and 5V.

- About timestamping - the hardware combo supports timestamping, it comes from the STM32MP157 chip. Can't say if I tested if the software supports it but even if it doesn't it shouldn't be hard to get it working.

- About the box - we don't have a custom box, however, the STMP board fits in the LIME metal box. There is just some free space at the side of the CAN controller (since the STMP board has no HDMI), check the pictures for each side:




The box is this one:

https://www.olimex.com/Products/OLinuXino/BOXES/BOX-LIME/

- About the software, I know for sure that in both STMP157 designs the CAN connector is tested empirically so there is CAN support in our Linux image. I can't say if in the OLinuXino board the second CAN is supported by the software (or if it can be enabled by the commands), but you can probably check the Linux configuration for the BASE EVB board (which has two CAN connectors):

https://www.olimex.com/Products/SOM/STMP1/STMP157-BASE-SOM-EVB/open-source-hardware

It is also good idea to take a look at this document about the Olimage Linux:

https://github.com/OLIMEX/olimage

[dry]

Thanks for reply @LubOlimex,

e side of the CAN controller (since the STMP board has no HDMI), check

Does this mean the board variant with CAN connection has no HDMI? Is there variant with VGA?
Could you help in case I order: which options / or option of the board Does come with CAN transceiver and port? Just so I don't get it wrong.

can't say if in the OLinuXino board the second CAN is supported by the software (or if it can be enabled by the commands), but you can probably check the Linux configuration

But are the 2nd CAN controller lines routed to the GPIO-x connectors on your board? I _think_ I see it in schematics, but I don't want to make mistake.

Thanks for the box, it will do.

Can I ask you, is the supply input strict 5V? Won't work from 12V by any chance..? (Sorry for dumb question in advance)

[LubOlimex]

- You can have HDMI and CAN but only in the STMP157-OLinuXino-LIME2H, STMP157-OLinuXino-LIME2H-EXT, STMP157-OLinuXino-LIME2H-SB variants of the board have HDMI (e.g. base STMP157-OLinuXino-LIME2-EXT has no HDMI). The HDMI also fits in the box:



- Now I checked you can have both CANs and HDMI; of course for CAN2 you need to place own transceiver chip and everything else that it needs like resistors and capacitors and pull ups and so on (maybe simply copy what we've done for the CAN around the SIT1050T), but the wires are led out to the headers - USART3_RX wire is PB12/CAN2_RX available at GPIO-1; DFSDM1_CKOUT wire is PB13/CAN2_TX available at GPIO-3; DFSDM1_DATIN1 is PC3/CAN2_STBY again available at GPIO-3.

- The power input is 5V only. If you only have 12V DC consider driving it down to 5V DC, if you have no own converter consider one of these:

https://www.olimex.com/Products/Power-Supply/Modules/DCDC6-16-TO5/
https://www.olimex.com/Products/Power-Supply/Modules/DCDC-36-5-12/
https://www.olimex.com/Products/Power-Supply/Modules/DCDC-50-5-12/open-source-hardware

If 220V AC are available simple adapter like this one would do the job too:

https://www.olimex.com/Products/Power-Supply/Adapters/SY1005E/

[dry]

If you only have 12V DC consider driving it down to 5V D

Thanks LubOlimex, I've asked this because I'm planning to do an automotive related prototype with this board, and hoped for luck I can power it from 12V battery.  (I will get your  ps adapter)

(maybe simply copy what we've done for the CAN around the SIT1050T)

.. I'm testing a couple of transceivers on my own board, so probably thinking to do a small like extension board or a connetor to somehow plug/connect into this STMP157 olinuxino's GPIOs, unsure yet. May be also cut-out hole for second  CAN connector on the side of that box - unsure best way.