This is the slowest and most stupid of our SCSI-drivers, but it is there
and it works. It has been tested with CD-ROM and disk.
It uses no interrupts, no DMA, just polled I/0.
Transfer-rate is <= 100Kbyte/sec.
If you set the jumpers on the board, you can change the unit-number and
you will be able to have four of these co-exist in one computer, why one
would do that is somewhat unclear though.
If I ever get my hand on the docs for this, I will improve it of course,
but for now we can install and access those CD-ROMs.
