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Re: How much of a ][ is needed to twitch?
- Subject: Re: How much of a ][ is needed to twitch?
- From: "Alex Freed" <alexf@mirrow.com>
- Date: Sun, 11 Feb 2007 18:59:23 -0800
- Newsgroups: comp.sys.apple2
- References: <45ce84be$0$83739$c30e37c6@lon-reader.news.telstra.net> <xcednTjqdZB4R1PYnZ2dnUVZ_rGinZ2d@comcast.com> <45cefcc4$0$83724$c30e37c6@lon-reader.news.telstra.net> <-fWdnWmyB9NSFFLYnZ2dnUVZ_tCtnZ2d@comcast.com> <45cfb024$0$52907$c30e37c6@lon-reader.news.telstra.net>
- Xref: g2news2.google.com comp.sys.apple2:17311
"Tristan Mumford" <xtristan.xmumford@xgmail.xcom> wrote in message
news:45cfb024$0$52907$c30e37c6@lon-reader.news.telstra.net...
>>
>> I am assuming this is the case because the Disk ][ Controller has
>> a reset generator that causes a longer reset pulse. If there had
>> not been an issue, this would not have been necessary.
>
> So that's why that is. It never occurred to me.
>
There *MAY* be a different explaination. Boot ROM at Cx00 is
only 256 bytes, so space is at premium. Better not to put a "soft"
delay there.
The first thing the disk code does is turns on the disk motor and moves
the head to track 0. Both actions draw a lot of power. Not good doing
it before the power supply is steady. Maybe that's why a longer reset
is needed when the disk drive is present?
-Alex.