Hi everyone, i've interfaced an 8051 µC with an SJA1000. an now am i looking for an CanOpen-Stack. Does someone have ever interfaced an 8051 with an SJA1000 and developed an CanOpen Slave? greetz Marek
Not real because i am lookin for canopen. i will try it.... but i don't think it will work.
http://www.esacademy.com/
Also worth a try. http://www.vector-cantech.com/
Yes i think thats it... A CANOpen Slave for an 8051 with an SJA1000 Controller.... but how much it cost?
but how much it cost? Why ask that in the forum, ask the provider. Erik
but how much it cost? why ask the forum, ask the vendor Erik
"Not real because i am lookin for canopen." Purely out of curiousity, what's the difference?
Purely out of curiousity, what's the difference? I haven't looked at them but I think the Keil drivers are simply low level drivers that allow you to send and received messages using the CAN controller. CANopen is a high level protocol that defines how the message ID field is used, how data is formatted in the message, network management services etc, etc, etc.
Why ask that in the forum, ask the provider. Right. All I can say is that what we paid was very reasonable considering the time and money it would cost to develop it in-house (probably a good man-year). The quality of the code is pretty good, it is highly configurable, their support is very good and there are no royalty fees. I'm not familiar with 8051 processors but one thing to consider is how many mailboxes the CAN controller has. If you don't have enough to handle the needs of the stack for things like NMT message, transmit and receive PDOs, SDO channels, emergency message and etc, the stack will probably work in the queued mode. This takes a lot of RAM which I get the feeling is a scarce commodity on at least some 5081 controllers. Also the way our stacks work, is it will process 1 message each pass through the code. So you have to consider how long it will take to execute each pass and how much time you can dedicate to running the stack to determine the response time to process incoming and outgoing messages. We use 16 and 32-bit processors which are pretty quick and have plenty of mailboxes but you might want to look closely at this when using an 8-bitter. Hope this helps.
so, CAN is a low-level transport layer, and CANopen is at a higher-level using the CAN transport. Is that it?
Andrew, Yes, that's right. Marek, I don't know why I didn't think of this before but the Embedded Systems Academy offers Micro CANopen source code for free. It's a scaled down version offering only the basic features of CANopen and you would have to write your own device specific drivers but it might be worth a look. http://www.microcanopen.com/