RE: [ha] CEBus

Vermeulen Nic (
Tue, 24 Nov 1998 14:25:10 +0100

Ha list,

A lot of reading indeed, Robin.
During my absence, so I looked around a bit and for the section
'hardware', there are a lot of interesting devices (Atmel, Thomsom,
Microchip). Very small processors with sufficiant power and isp
The networking part is another story. Apparently, the first barrier is
the network and the protocol. Without a clear description, I don't think
we can start with the hardware design (what to use for physical layer?).

I browsed the CeBUS manual a bit, and I could not find a layer 1 & 2
definition. To be honest, I didn't find anything on the web that came
close to that except for the RS485 specs. There are a lot of fieldbusses
(HART, Bitbus, Profibus, CAN...) but no one is eager to tell the whole

Maybe an interesting device for powerline communication is the Philips
TDA5051? Can it be used if the protocol has a CSMA/CR scheme? (bit

The ultimate question is: do we adopt some existing communication
standard (ease of use, compatibility, devices in silicon) or do we try
to design our own (based on something known? are we capable?). The CeBUS
CAL is fine, and if it becomes a standard, devices with build in
protocol will become available (like CAN & philips MCU's) but I don't
it's easy to write such a stack for let's say a 90S1200.

Until we clear this out, I think we're stuck at zero. Don't want to
discourage anyone, just some thoughts that popped up.

OK, I'm gonna wade through the 300p specs. See if I can get on to the
same conlusions as Robin.


PS: Where is everyone. I thought my mailbox would flow over during my