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Need help, need to delay the BE going high by at least 200nS after the RES line goes high. This is to force the W65C134 to use the external ROM from the start. I have proved that this works with using a pushbutton to hold the BE low till after the reset.

Any suggestions would be welcome.

I have attached the schematic for the W65C134SXB board that I am using.

You could just use something like a DS1318 to hold it low, it will do so for quite a while though (100ms or more, I think).

You can also use an RC circuit through a Schmitt trigger to wait about the right amount of time.

Or feed your clock signal through a counter to count the right number of clock cycles for your delay.