Re: FPGATED

From: silverdr_at_wfmh.org.pl
Date: Tue, 26 Jul 2016 08:22:46 +0200
Message-Id: <FA308099-AFEF-4E75-A8DD-DB66F1D2CB6A@wfmh.org.pl>
> On 2016-07-25, at 23:51, Hegedűs István <hegedusis@t-online.hu> wrote:
> 
> ... and when it comes out of TED it is called BA
> 
> -----Original Message----- From: Spiro Trikaliotis Sent: Monday, July 25, 2016 10:26 PM To: cbm-hackers@musoftware.de Subject: Re: FPGATED 
> Hello,
> 
> * On Sun, Jul 24, 2016 at 10:06:55PM +0200 silverdr@wfmh.org.pl wrote:
> 
>> Or changed, I'd say. Actually I recall seeing _HALT or _HLT more than
>> once in the old days (and not from your posts, Gerrit :-). I even
>> remember that I was later looking "where the heck is that pin about
>> halting the CPU?!" before I realised it's named differently. Don't ask
>> me where it was though.
> 
> As the 6800 pin is called "-HALT", that might be the reason why some
> people called it so on the 6502, too. ;)

Possibly. Especially that I guess, I am not the only one for whom it makes more sense.

> I believe the MOS hardware manual introduced the name RDY, but it also
> directly compared it to the HALT on the 6800 (chapter 1.2.1, p. 12, on
> Hardware Manual from Janury 1976, 2nd edition, Revision A,
> http://users.telenet.be/kim1-6502/6502/hwman.html)

Interesting read.

6800                              6501
Halt - Stops processor [...]      Ready - Stops Processor [...]

The only reason I can think of is that they wanted to somehow differentiate from how 6800 handles the signal (after completing the current instruction) as opposed to how 65xx does, but the choice of the name still seems like an unfortunate one for me. And they didn't change name for the VMA pin for example, even if the behaviour is different..

-- 
SD!


       Message was sent through the cbm-hackers mailing list
Received on 2016-07-26 07:00:03

Archive generated by hypermail 2.2.0.