[TUHS] Fwd: Choice of Unix for 11/03 and 11/23+ Systems

[Noel Chiappa]

    > Would also be great if supported RL02 drives. ;)

_Support_ for RL02's will not be a problem (but there are probably some issues
- see below). I have an RL11 driver for V6, which will be easy to include in a
system build. There is also a RL V6 boostrap (which lives in block 0 - it
loads the OS from a V6 filesystem); how to load it off the RL pack on actual
hardware, I'm not sure; do you have some PROM device that has an RL bootstrap
in it?

Or do you have some other drive which is going to be your boot device? If not,
how are you going to get the bits onto an RL pack? This was a bit of an issue
for Fritz Muelller with his -11/45 (with an RK05 drive); he finally wound up
having to load it over a serial line, which took several hours. He used
something called PDP11GUI, and you're in luck, that does support RL02's.

Also, I'm not sure if you've had any experience with an old removable-pack
drive. If not, you have to be very careful with them; if you have a head
crash, the heads are now unobtainium, so a head crash will turn the drive into
junk. (Which is a big part of why Dave Bridgham and I are doing to QSIC RK11
emulator...) The packs need to be absolutely clean; a number of people have
experience with them, you should probably qget some lessons from them before trying
to use it.


    > I'd imagine the V6 TTY driver would support boards with multiple serial
    > ports. Guess that's what's needed for multi user access.

The TTY code in V6 consists of two levels of driver. The bottom layer is a
driver which is specific to the particular type of card one's using; DL-11,
DZ-11, etc. If the card supports multiple lines, that driver will too. Then
there's a layer above that, tty.c, which the low-level driver uses to interace
to the OS; the user talks to that. That layer is multi-line.

   Noel