Windows 1.0 For DEC Rainbow (mirror of Latrobe ftp anybody ?)

Warner Losh imp at
Thu May 4 21:17:35 CDT 2017

On Thu, May 4, 2017 at 7:58 PM, Fred Cisin via cctalk
<cctalk at> wrote:
> On Thu, 4 May 2017, Warner Losh via cctalk wrote:
>> The old fashioned way: copy the files on the rainbow to the hard
>> drive, kermit to my unix box.
>> I have a kryoflux, but it's being nothing but frustrating to me since
>> I don't know if I have a known good floppy it supports or not. I mean
>> I have two 5.25 1.2M floppy drives, just have no way of knowing if
>> they are good or not and am loathe to try to buy another one...  So
>> I'm reading them the only way I know how: via an RX-50 on my
>> Rainbow...
> Rainbow disks are readable on a PC with 1.2M.  But, it's sometimes a little
> easier if you use a 720K 5.25" drive.

True. I have two I bought back in the day for the Rainbow that I've
not been able to get to work on my PC or kyroflux. They are TEAC

> 96tpi, 300 RPM with 250K data transfer rate
> (or, with some 1.2M drives: 360RPM with 300K data transfer rate, but NOT
> double stepping as would be done for 360K disk at that data transfer rate)

Correct. I've done it before years ago on FreeBSD, I thought with the
TEAC 55FRs, but it may have been with the 55GRF that I have...

> There are commercial programs available for the PC to read/write Rainbow,
> and even programs for the Rainbow to read/write PC 160K/180K disks.
> (for writing PC on the Rainbow, start with a virgin disk, and format it on
> the Rainbow in PC format, or in a PC using a 1.2M drive in 190K format -same
> track width problems as rewriting 360K disks in 1.2M drive)

Yes. And you could use the IMPDRIVE.SYS that I wrote and put a 720k
3.5" drive into the Rainbow and do the transfer that way too, since it
allowed you to read/write standard IBM disks. Trouble with that is
that my newer computers don't even have a floppy port and the older
ones in the bone yard are broken... I have 40 or 50 backup disks that
I should read into the my unix boxes sometimes.


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