Re: mos 6551 / w65c51

From: laughton_at_cyg.net Date: Wed, 18 Oct 2023 09:04:46 -0400 Message-ID: <9586b21593a959f2bd91032bbf567ba5_at_cyg.net>

It's my understanding that all 65C51's made by WDC are affected, but all 
other versions such as mos 6551 are free of the transmit flag bug.

More on the bug on 6502.org, here:
http://forum.6502.org/viewtopic.php?p=26524#p26524

-- Jeff

On 2023-10-18 08:45, didier_at_aida.org wrote:
> Hi All :)
> 
> I made a board with a 65c816 and a 65c51
> I saw on the web that apparently the w65c51 has bug on the transmit 
> flag ...
> is there a way to identify the w65c51 with or without bugs ?
> I checked the plus4 rom code to check how the 6551 was programmed
> 
> is this bug only on the w65c51 or also on the mos 6551 ?
> 
> my goal was to study how to replace a mos 6502 by a 65c816... on a
> commodore 8032
> have a board with ram + 64ext on the board and run at 1 Mhz on the I/O
> and faster speed while accessing the ram  (8Mhz)
> 
> thanks