Re: The 6502 is a dynamic CPU, the Z80 is a static one

From: smf <smf_at_null.net>
Date: Mon, 4 May 2020 18:58:44 +0100
Message-ID: <293debf5-5cd8-96f9-454f-4bcd1fd000f6_at_null.net>
On 04/05/2020 18:38, Jim Brain wrote:
> The original NMOS design relies on the fact that the charge on a wire
> will continue to live there for 300nS or so, as part of the operation
> of the 6502.  On the 65C02, such things were dumped into flops, to
> avoid the issue.
>
This may have been the same for the Z80, the CMOS versions are fully
static but the NMOS ones may not have been.

https://retrocomputing.stackexchange.com/questions/13584/zilog-z80-freezes-while-binary-counting-up-to-65-536-216
<https://retrocomputing.stackexchange.com/questions/13584/zilog-z80-freezes-while-binary-counting-up-to-65-536-216>

Registers are equivalent to RAM & the program counter is continuously
updated, they were more worried about speed and cost than being able to
run on low power.

The original 68000 wasn't fully static either.
Received on 2020-05-30 01:38:13

Archive generated by hypermail 2.3.0.