I do have my home automation build on CAN nodes with teensy-3.2. I went into the rabbit hole of the Board design with some sucess (https://wiebel.org/CANNode/ for those who are interested) I used to have a RasPi with an SPI CAN controller as a Gateway, I always wanted to go for a Beaglebone Black because of it's native DCAN. So I ordered the RS485/CAN Cape from waveshare. It looks like it's the only Cape available for a reasonable price. After ordering I checked the Schematics and got shocked about how awful the design was. - shared TX/RX for CAN and RS485 so you can't use both - DCAN0 is not accessible - forced 120Ohm termination, no jumper to turn it of - Rs is pulled down by 10k
I got over or around the first points (desoldered the 120Ohm). But the last one bit me, althoug I haven't noticed it at first glance. All CAN bus activities are suppressed as long as the Interface is not properly enabled in the beaglebone. I figured to better enable it right at boot time, turns out that is not noing to happen in early boot. After some reasoning I noticed that the flexcan library on the teensy very well supports the Rs pin which I have connected to a gpio, So the Tranceiver gets enabled when all is set. As it seems like I have to roll my own cape I'd rather try to make it properly. So here are my questions: - Is there any predefined way for the dcan driver to enable the tranceiver or do I need to fix it manually? - What pin might be prefereable for such a need or is least often used by other capes? - What is the initial state of the pins at boot time The Datasheet of the AM3358/9 have no mention of additional pins used for CAN. -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/beagleboard/cb375603-f8de-46c2-81ff-90a0fb93f5f7%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
