Hi,
I have a job coming up involving the switching of around 40-60 digital I/O and 10 analog inputs and about 20K of code on a Cygnal 8051 based SBC.

I was intending to use the SBC plus an I2C chip on each
output board (8 outputs on each) The job involves some low level safety critical hardware used in hospitals.

My customer is absolutely hell-bent on using a PC based SBC running windows NT embedded and an RS485 loop for the I/O cards, which will have to be designed with some intelligence on-board (uP+software). I think this is a ludicrous solution, considering the overkill and the general unreliability of Windows.

Has anyone any suggestions? i.e. How can I persuade my customer (or should I?).
Chris