Hi all

sorry i am using 74HC devices only.

Decoupling is done at the Supply pins of strip connector on the main board with 1uF Tantalum and 0.1 ceramic in parallel. Separate ground line for analog circuit.

Regarding Speed I need 50 MIPS for this application.

We have installed around 10 systems. at one place only it is giving lot of trouble.

i am gettng probelm only when i drive AC solenoids. some places i am driving DC solenoids 24V 2A with out any problem. 24V is from SMPS.

all the AC solenoids are given snubbers across coil.

my thinking is CPU is internally running at 50mhz and externally signals are less than 5khz . still is it requires 4 layer board?

i am running Philips RD2 at 22.1184MHZ in X2 clock mode (44.2mhz performance). but no problems yet.

Thanks for all.

!!Happy Dewali!!

Haribabu.