Re: Commodore 15 Second disk format routine disassembled

From: Francesco Messineo <francesco.messineo_at_gmail.com>
Date: Sat, 11 Apr 2026 10:40:15 +0200
Message-ID: <CAESs-_whMjkowbgYM2no1BAYfySujsKJhY_DScnUS3VxqySK-w_at_mail.gmail.com>
The first fast format routine I've seen in the old days was the
"speeddos plus" one that was a very popular 1541/C64 hardware mod in
Italy since 1984 (if memory works). I think the speeddos plus
modification originated in Germany..
I seem to remember that it would just write each track without reading
back the sectors but I may be very well wrong after all these years. I
still have two speeddos plus systems, one is my original C64 and one
is an SX-64 donated from a local friend. Both were modified around mid
1985.
Frank IZ8DWF

On Sat, Apr 11, 2026 at 10:27 AM André Fachat <afachat_at_gmx.de> wrote:
>
>
>
> Am 11. April 2026 03:27:33 schrieb Jesus Cea <jcea_at_jcea.es>:
>
>> You could be interested in this:
>>
>> https://x.com/commodoreihs/status/2040555413326672219
>>
>> """
>> It took over a minute and a half to format a new disk using the native
>> Commodore 64 / 1541 disk drive commands. Mike J. Henry of Starpoint
>> Software and Basement Boys Software (Fast Hack-'em) fame wrote a 15
>> second format routine, which was apparently at some point modified by
>> Alf Maier. I don't know exactly what Alf modified, but I think this was
>> widely distributed on QuantumLink in the mid-to-late 80s.
>> You can download the program from Bo Zimmerman's site here:
>> https://zimmers.net/anonftp/pub/cbm/c64/diskutil/routines/Format%2015%20seconds.prg
>> I disassembled the code and uploaded the result to GitHub:
>> https://github.com/commodoreihs/15_second_format/tree/main
>> Does anyone know the precise history of 15 second format?
>> """
>>
>> https://github.com/commodoreihs/15_second_format/tree/main
>>
>> https://zimmers.net/anonftp/pub/cbm/c64/diskutil/routines/Format%2015%20seconds.prg
>
>
> Very cool work by Dave!
>
> That reminds me of the 12s format routine I once submitted to the German 64er magazin.
>
> It came back a remark on the paper 'bringen wenn funktioniert' which means publish it if it works. Which it didn't of course. I only had a single 1541 to test on, so it was a classic 'works on my machine'.
>
> I will certainly look into that routine!
>
> André
>>
>>
>> --
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>
Received on 2026-04-11 10:00:16

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