front panels

From: Hans B Pufal <>
Date: Tue Feb 24 10:00:19 1998

Allison J Parent wrote:
> The 8008 does not have memory mapped IO, there are distinct IO
> instructions. It's not to say MM/io is not done. The PDP-11 memory
> and devices are the same things and there are no specialized IO
> instructions.
> The altair...(8800 and 8800a) from the front pannel there is no way to
> interrogate an port mapped IO device or write to it. You must do it with
> a little code.

But surely this is a limitation of the front panel not the processor.
I/O bus cycles can (easily) be generated from an appropriately designed
front panel.

 Hans B. Pufal : <>
 Comprehensive Computer Catalogue : <>
Received on Tue Feb 24 1998 - 10:00:19 GMT

This archive was generated by hypermail 2.3.0 : Fri Oct 10 2014 - 23:30:54 BST