30 Sep
2023
30 Sep
'23
10:18 p.m.
On Sep 30, 2023, at 1:32 PM, Johnny Billquist
<bqt(a)softjar.se> wrote:
On 2023-09-30 19:04, Robert Armstrong wrote:
No. You can start with that interrupts are handled completely differently to a PDP-11,
and this then immediately leads to a console terminal driver will not work on the Pro.
Non-interrupt driven communication to the console is the same as a PDP-11, so some
diagnostics are possible. But any OS will be interrupt driven, so everything related to
interrupts needs to be done differently.
And no, nobody have done this. Part of the bigger problem is that the device drivers for
the Pro disk controller is not around, so any porting would require rewriting that one, as
things stand.
In RSTS/E 10.1, the INIT component (the part that boots first, discovers the hardware, and
then asks you if you want to "start timesharing" does ship with the Pro support
included. So you can take that code and put it onto an RX50, then write the
"DZ" bootstrap (RX50 Pro bootstrap). My utility "FLX" can do that.
And yes, that includes just enough of the interrupt controller machinery to poke at
devices and verify they interrupt correctly, a "glass TTY" console display
driver and keyboard driver, and the RX50 and hard disk controllers. No extended video, no
networking, though it will recognize the presence of the extended video feature, and it
will also recognize the 4-line UART board. But the OS support for all that is only in my
workspace, awaiting me getting enough tuits to send it out
paul
Johnny
Billquist <bqt(a)softjar.se> wrote:
DEC in all it's wisdom decided to make the Pro hardware not really that
PDP-11 compatible. So any OS that you want to run on the Pro will need
to be rehacked in order to make it possible.
I thought it was mostly a matter of
device drivers for the PRO
peripherals, which are all non-standard (when compared to their real PDP-11
cousins). And I thought somebody had already done this. FWIW, I thought there also existed a similarly
modified version of RT11
for the PRO too.
Yes. DEC did provide an unsupported version of RT-11. Included drivers that were needed
for the Pro. I *think* they also do the console on the graphic subsystem, which again is a
bit of work.
I *think* Paul also have the never officially released port of RSTS/E for the Pro. But
noone did a port of RSX - after all, they had P/OS...