18 May
2026
18 May
'26
2:10 a.m.
On Sun, May 17, 2026 at 7:46 PM Robert Armstrong via cctalk <
cctalk(a)classiccmp.org> wrote:
I have a Rainbow 100A with the Univation hard disk.
Works (wow!), but
the
Univation HDD controller was not DEC compatible and you have to boot from a
floppy to get the disk drivers loaded. And of course, the 100A ROMs
didn't
support any kind of hard disk, DEC or otherwise.
Correct.
Did anybody ever make an updated ROM image for the
100A that supported
booting from the Univation directly? I think the 100A used 2716 EPROMs,
and it'd be easy enough to burn some new ones.
Not that I ever heard of. But I didn't sail too close to the 3rd party
marketplace.
The Univation HDD controller connects through SASI to its hard disks (which
were sold with a SASI to MFM adapter board). I disassembled the driver in
the
hopes of using the Univation card I bought on ebay, but I wasn't able to get
my card working: the system always hung for me, even when messing with
the jumpers (I have a Rainbow 100B from back in the day I take out and
play. with from time to time). I had hoped to add Univation sport to Venix,
but I gave up on that in part due to the booting issue. Univation also has a
different on disk partition table than the DEC controller used.
https://github.com/bsdimp/rainbow100.git has my efforts, in
3rdparty/univation.
./rainbow100/3rdparty/univation/src/univdrv.S has fully comments source. I
think
I use the gnu assembler, not masm, there. It's been a while and I've not
checked
tonight. It's too late, but I had to reply.
Warner
And is there any surviving documentation for the Univation? Bitsavers
seems to have nothing.
Thanks!