CANBus board

[Brian]

Is there a good demo board out there to learn canbus?

 

[Dave]

Is there a good demo board out there to learn canbus?

Yes, many.

Please narrow your search a little and then suggestions can be made.

 

[Brian]

Yes, many.

Please narrow your search a little and then suggestions can be made.

I am unsure how to narrow it. Just something to learn canbus, hardware with
perhaps a tutorial with it. Perhaps remote switches or some simple app.

 

[Dave]

I am unsure how to narrow it. Just something to learn canbus, hardware
with perhaps a tutorial with it. Perhaps remote switches or some simple
app.

Well it's not just a case of picking up a board and learning it. Check out
the Bosch specs. for a start then also look at CiA website. Vector website
is another good one and there's some stuff on NI as well.

Do you just want to learn about the protocol or do you have a possible
application in mind?

I assume you want to do something practical which is why you want a board,
so what is your experience of programming languages and microcontrollers?
What do you already have available? There are many micros. with the CAN
controller built into it including cheaper leaded parts such as AVR and
Microchip, both these have information on their website and I know Microchip
provide development boards with CAN.

You could just get a couple of SJA1000 CAN controllers with the necessary
other hardware and program a couple of PC's to communicate with them via.
the parrallel port. If you have a bunch of money available then buy CAN
boards for the PC from the likes of Vector or NI and work with these.

Like most things, there are many options and much to learn.

 

[Rich Webb]

Well it's not just a case of picking up a board and learning it.

If the OP's new at this, he may not realize that working with CAN
requires at least two properly configured boards in order to complete
the ACK sequence. Some dev board vendors include a pair of boards in
their kits; ST did for at least one 8051-based CAN product but I don't
have the part number handy.

Some type of CAN bus monitor/sniffer is probably a good idea as well,
and it can serve as the second device, if necessary. I've pretty happy
with a Peak Systems PCAN-USB device (distributed by
http://www.gridconnect.com/usbcanin.html) that includes a basic
click'n'run monitor as well as a Windows programming API so that it
can be integrated into, e.g., lab test apps.

 

[Dave]

If the OP's new at this, he may not realize that working with CAN
requires at least two properly configured boards in order to complete
the ACK sequence. Some dev board vendors include a pair of boards in
their kits; ST did for at least one 8051-based CAN product but I don't
have the part number handy.

Some type of CAN bus monitor/sniffer is probably a good idea as well,

Absolutely. When I started I was fortunate enough to get my hands on a
CANAlyzer which makes a huge difference in getting started.

and it can serve as the second device, if necessary. I've pretty happy
with a Peak Systems PCAN-USB device (distributed by
http://www.gridconnect.com/usbcanin.html) that includes a basic
click'n'run monitor as well as a Windows programming API so that it
can be integrated into, e.g., lab test apps.

It's important for the sniffer to be able to turn off the ACK, I've used the
PCAN briefly but not set it up so don't know if this is possible. Otherwise
that is a good start and they are relatively cheap.

Also if the OP is new we should just clarify at the start he will need a
total bus impedance of 60 Ohm and this should be made up of two 120 Ohm
resistors, one at each end of the bus. That one always seems to crop up,
and not just with new users!

 

[Rich Webb]

Absolutely. When I started I was fortunate enough to get my hands on a
CANAlyzer which makes a huge difference in getting started.


It's important for the sniffer to be able to turn off the ACK, I've used the
PCAN briefly but not set it up so don't know if this is possible. Otherwise
that is a good start and they are relatively cheap.

Yes, that would be useful. As far as I can tell, the PCAN gizmo
doesn't expose that capability in the supplied monitor or "lite"
version of the DLL that is included free. The controller in the dongle
is an NXP SJA1000 (which does have a listen-only mode), so it's
possible that the full version exposes more functionality.