View Full Version : 10k PDs on Address Lines?

April 11th, 2012, 09:55 AM
Is the above acceptable in a PC or PC/XT?

I need A15 on a ROM to be ground or connected to the address bus A15 (user selectable via DIP switch preferably). But I was wondering whether it would be acceptable to have a 10k PD on that line?

Many thanks!

April 11th, 2012, 12:06 PM
I suppose that bus loading would be negligible and so okay, but essentially you're saying that bus A15 will have a PD all of the time? Did you run out of I/Os on your CPLD?

April 11th, 2012, 12:55 PM
Thanks, yes always with 10k PD on that line alone. It's for my ROM board (actually flash of course), to enable the user to select 32 or 64k operation (in a single window) by switching A15 on to the ROM, and off for the comparitor.