Okay I'll try to keep this simple:

I have a six pin ribbon cable that is 10 feet long. I am connecting 5
devices on the bus. Each device will draw <200mA @ 5-6V from the cable.
I will be using a hardware SPI from a AVRTiny on each board. Now my
question is: Can I actually just use SPI to get the devices to talk
resonably? I don't mind low bit rate spi. Something like 800 bits per
second would even work. Is there something special I should include in
the design? I've blown the budget already, so I'd like to keep it simple.

Thanks,

Brett

Brett Foster wrote:

Multiple times 200mA from a flat ribbon cable is a lot.

Rene
--
Ing.Buero R.Tschaggelar - http://www.ibrtses.com
& commercial newsgroups - http://www.talkto.net

"Brett Foster" <fosterb.no.s.p.a.m@ioctl.ca> wrote in message
news:38l6qiF5p0qipU1@individual.net...
I don't think that you have enough wires for SPI. As well as the four wire
SPI you'll need chip selects on the slaves. I2C would be more suitable as it
uses 3 wires and doesn't need chip selects when used as a bus. You should be
able to find I2C implementions for the AVR.
Peter

"Brett Foster" <fosterb.no.s.p.a.m@ioctl.ca> wrote in message
news:38l6qiF5p0qipU1@individual.net...
It will probably work. SPI is used to program AVRs and it works OK over 2 m
or so of printer cable.

Leon