Re: [bascom] RS485


From S_JBecker@t-online.de (Joerg Becker)
Date Fri, 1 Oct 1999 19:03:09 +0200

Hi Eric,
I have done some projects with CAN-interface professionally. 
There are essentially two ways towards CAN:
- use a controller with integrated CAN-module like Philips 80C592 (this is an 
  80C552 with integrated 80C200 CAN controller), Infineon (former Siemens) 
C505 
  or C515. These are 8051-compatible controllers and you get some good 
  application notes on the Philips and Siemens web servers.
  If you do not like 8051s so much (like me) there are a lot of other 
  controllers around. We use a 16bit 128k Flash ROM Fujitsu MB90F598, which 
is a 
  very nice chip (with free C-compiler), cost about 12 Euro.
or:
- use your favourite controller with an external so-called stand-alone CAN   
  controller. We for example use an Atmel AVR AT90S8515 together with a 
Philips 
  SJA1000 (about 3-4 Euro). 
  Again there are good application notes on the Philips server. The SJA is   
  connected to the multiplexed adress/data-bus and is quite easy to use. 

Apart from these controllers you will also (in almost any case) need a 
separate 'driver' chip, a so-called transceiver (e.g. philips 80C250). The 
transceiver will translate the TTL-levels of the controller to the 
differential 
CAN-bus signals.
  
I would recommend to use a controller you are familiar with in connection 
with 
the SJA1000. 
If some command sequences as C-sources would help you, please tell me, but I 
am 
first going to have holidays (yes, really) next week and leave in about two 
or 
three hours, sorry. I will be back on the 12. of october.

Cheers, Jörg. 


Eric Le Baron wrote:
> Would you recommend a uC with build in CA support or use a separate Can
> driver ?
> Suppose those drivers exist ?