Greetings everyone,

I'm working on a hobby project using a 12C508 to turn on and off the lights
on a model train locomotive. The locomotive has an ID ( 1 ~ 80 ) on the
track. The decoder circuit based around the 12C508 needs to have ID
selection switches by which I can assign the decoder an ID.

I can use a bigger chip and waste 4 pins just to hardwire the ID with DIP
switches or jumpers which seems a waste for such trivial thing. I was
looking at the AN512 Ohmmeter/Temperature sensor application note where I
could use a variable resistor to select the ID or the other thought was to
have a simple flasher circuit to clock the T0CK pin and then read the TMR0
register after a fixed amount of time to get the locomotives ID. Have a
variable to vary the pulsing rate of the flasher circuit.

Am I wasting my time with the 12C508 chip here and should just use a 16F84?
Does anyone know when the 12CE518 chip would be available? With that (and
also with the 16F84) I could write a routine to actually program and store
the decoders ID in the EEPROM by using a key sequence on the central
control unit.

I've got a few 12C508 around right now but I dont have any 16x84's which is
why I was just trying to use the 12C508 chip. If anyone has any ideas on
implementing a way to assign the 12C508 chip an ID (1 ~ 80) through
external circuitry which the chip can pick up during its program
initialization stage, I would like to hear it.

Thanks!

Shahid