Synertek 6507

From: Eric Smith <eric_at_brouhaha.com>
Date: Thu Mar 13 21:40:01 2003

Tony wrote:
> Think of the 6507 as (very) programmable counter chain (in the simplest
> case just have it executing NOPs and JMPs).

Typically you want some instruction other than NOP. For instance,
using LDA immediate lets you fetch consecutive addresses on every
cycle.

> I once had this idea (which I've never followed up) to use a common,
> fast, 8 bit processor with no instruction pipelining (so you know what
> the buses are doing and when) as a microcode sequencer. Just give it 8+n
> bit wide memory, with the 8 bits consisting of NOPs and (conditional)
> jumps. the n bits are the control lines to whatever you're microcoding.

Back in 1993 or so, I was thinking about using an AMD 29005 RISC
microprocessor as a microprogram sequencer for a 36-bit computer.
But the 29005 doesn't qualify as common.
Received on Thu Mar 13 2003 - 21:40:01 GMT