Re: Converting a Commodore 64 from NTSC to PAL

From: Pasi 'Albert' Ojala <>
Date: Fri, 13 Apr 2012 23:57:27 +0300
Message-ID: <>
On 04/13/12 20:59, Gerrit Heitsch wrote:
> So unless the circuit that converts the 9V AC into a 50 Hz TTL-signal 
> contains some kind of filter, the TOD clocks cannot be accurate.


There is nothing impossible about using a filter at the TOD input pin, 
and it can have input hysteresis to guard for noise.

At least I remember the TOD clock was pretty accurate 20 years ago when 
I used it in my bbs software. I also used the TOD interrupts to keep 
track of the date, and had an asm routine to "sprintf" the time and date 
(with weekday) into a basic variable.

AIKA: 01:27.10  Sun 07.08.88


       Message was sent through the cbm-hackers mailing list
Received on 2012-04-13 21:00:05

Archive generated by hypermail 2.2.0.