16 Jun
2014
16 Jun
'14
3:26 p.m.
On 06/16/2014 02:37 PM, Eric Smith wrote:
On Jun 16, 2014 10:38 AM, "Chuck Guzis"
<cclist at sydex.com> wrote:
Can you really cut the gaps short enough to do that
reliably? I'd expect
to need really tight motor speed control.
On an 8" drive, I don't think it's a problem. At any rate, Digital
Group, Octagon and Wave Mate used the 9x1024 track layout. I'd be more
concerned with an early (belt-drive, open-loop tach) 5.25" drive.
Most everything is easy on those. Except formatting a
disk with certain ID
field values betwen 0xF5 and 0xFF.
Just get yourself a WD1781 and pick whatever address mark set suits you.
Not very easy to find those--WD had problems with them and dropped
them from the 1984 databook. I've still got a couple--very useful if
you want to do something like MMFM or other nonstandard encoding.
And the 765 is even less tolerant than the 179x when it comes to address
marks (and layout).
The machine only supports 65KiB of RAM (64KiB DRAM and
1KiB SRAM), so that
would seriously reduce the TPA size.
Ah, too bad--setting aside 9K for a track buffer might take a too-large
byte, but maybe not. To bad there's no bankswitching hardware in your box.
--Chuck