Which RT-11 for an 11/03

[Mattis Lind]

>
> SIMH has never directly supported mounting/attaching virtual TU58 devices.
> Altho the required serial interface
> is emulated (ie, a plain DL11 at 776500/300) the TU58 drive behind the
> serial interface has never been emulated.
>
>
>
I just tested the latest SimH from github and it is indeed possible to
enable tdc and attach an image file to the tdc0 device. I then booted into
RT11 from a DU-device and did INIT DD0: no problem.
Then I made a bootable DD image. I did even do a BOOT DD0: which gave me a
RT11-prompt. But booting from SimH failed on me. I am not sure why.

MattisMacBook:BIN mattis$ ./pdp11
PDP-11 simulator V4.0-0 Beta        git commit id: 1b6f28a7
sim> set tdc enable
sim> attach tdc0 rt11-dd.dsk
TDC: creating new file
TDC: buffering file in memory
sim> attach rq0 rt11v53-games.dsk
sim> b rq0

RT-11SJ  V05.03

.init dd0:
DD0:/Initialize; Are you sure? Y

.copy dd.sys dd0:
 Files copied:
DK:DD.SYS      to DD0:DD.SYS
**** Copying some files *****


.copy rt11sj.sys dd0:
 Files copied:
DK:RT11SJ.SYS  to DD0:RT11SJ.SYS

.copy/boot rt11sj.sys dd0:
.boot dd0:

RT-11SJ  V05.03

.dir

DD    .SYS     5P 20-Dec-85      TT    .SYS     2P 20-Dec-85
SWAP  .SYS    27P 20-Dec-85      STARTS.COM     1P 20-Dec-85
DIR   .SAV    19P 20-Dec-85      DUP   .SAV    47P 20-Dec-85
DU    .SYS     8P 20-Dec-85      RT11SJ.SYS    79P 20-Dec-85
 8 Files, 188 Blocks
 316 Free blocks

.boot du0:


RT-11SJ  V05.03

.

Simulation stopped, PC: 146414 (BCC 146446)
sim> exit
Goodbye
TDC: writing buffer to file

PDP-11 simulator V4.0-0 Beta        git commit id: 1b6f28a7
sim> set tdc enable
sim> attach tdc0 rt11-dd.dsk
TDC: buffering file in memory
sim> b tdc0


Trap stack push abort, PC: 000000 (WAIT)
sim>

I have no idea why SimH is not able to boot from the simulated DD0: device.
The steps to make a bootable dd0: was exactly the same steps as to make a
bootable RK0: which works just fine.


Ersatz-11 on the other hand works fine with the same image:

E11>assign tt1: dda:
E11>mount dda0: rt11v53_dd.dsk
E11>b tt1:

RT-11SJ  V05.03

.dir

TT    .SYS     2P 20-Dec-85      DD    .SYS     5P 20-Dec-85
RT11SJ.SYS    79P 20-Dec-85      SWAP  .SYS    27P 20-Dec-85
STARTS.COM     1P 20-Dec-85      DIR   .SAV    19P 20-Dec-85
RESORC.SAV    25P 20-Dec-85
 7 Files, 158 Blocks
 346 Free blocks

.


This is the image that boots in Ersatz-11 but not in SimH:
https://dl.dropboxusercontent.com/u/96935524/rt11v53_dd.dsk.gz
Since it boots on Ersatz-11 when set to 11/03 CPU it should work on the
real hardware.

BTW. It not so that the LTC interrupt is enabled in your system? I have had
problem with that one. In certain cases it need to be disabled. If I
remember correctly I had problems booting RT11 from MSCP devices with LTC
enabled.

/Mattis



> Don
>