Which RT-11 for an 11/03

Richard Cini rich.cini at verizon.net
Thu Mar 10 19:24:51 CST 2016

Gary, et. al.--

Ok, I spent some time trying this again, and here’s what I did. The system is very basic — LSI-11 CPU, 32kw of RAM and two SLU cards. Using PDP11GUI and TU58em emulator. XXDPD2D tape image loads and runs properly with this configuration and the standard boot loader.

Based on the instructions on Malcom Macleod’s site, I prepared an RT-11 TU58-target tape image from the base RK05 image from the SIMH distribution. The key incantation is:


What this should do is make the disk image bootable as a TU58 image. 

Next, I fired-up TU58em, loaded the boot loader into the H11 and ran it. Here’s the log from TU58:

D:\DEC>tu58em -v -p 3 -s 9600 -w rtv4_dd.dsk >>log.txt
info: unit 0 rw   file 'rtv4_dd.dsk'
info: serial port 3 at 9600 baud
info: TU58 emulation start
info: R restart, S toggle send init, V toggle verbose, D toggle debug, Q quit
info: emulator started
info: boot     unit=0 blk=0x0000 cnt=0x0200
info: read     unit=0 sw=0x00 mod=0x00 blk=0x0002 cnt=0x0800
info: read     unit=0 sw=0x00 mod=0x00 blk=0x0006 cnt=0x0400
info: read     unit=0 sw=0x00 mod=0x00 blk=0x0008 cnt=0x0400
info: read     unit=0 sw=0x00 mod=0x00 blk=0x000A cnt=0x0400
info: read     unit=0 sw=0x00 mod=0x00 blk=0x000C cnt=0x0400
info: read     unit=0 sw=0x00 mod=0x00 blk=0x0134 cnt=0x0A00
info: read     unit=0 sw=0x00 mod=0x00 blk=0x0085 cnt=0x0132
info: read     unit=0 sw=0x00 mod=0x00 blk=0x0086 cnt=0x3CC8

At this point, the RUN LED goes off and the system halts.  It looks like the boot loader is loading and running the second-level loader on the tape, but something happens after that. Not sure where to go from here. 

Thanks all!


Rich Cini
Collector of Classic Computers
Build Master and lead engineer, Altair32 Emulator

On 3/10/16, 5:51 PM, "cctalk on behalf of Richard Cini" <cctalk-bounces at classiccmp.org on behalf of rich.cini at verizon.net> wrote:

Thanks Gary. This is my understanding as well since everything works with XXDP right from DEC and I'm not using the H-27. So, I remain optimistic that I can get this working. 


Sent from my iPhone

 On Mar 10, 2016, at 5:46 PM, Gary L. Messick <Gary at realtimecomp.com> wrote:
 There is no difference in the LSI-11 board on an H-11 and a pdp-11/03.  What DEC did do was cripple Heath's version of RT-11 (called HT-11).  It would only work with Heath's H-27 floppy drive unit.  The Heath serial, parallel, and memory cards were all compatible with DEC's offerings, AFAIK.
 That being said, I personally don't have experience with true RT-11 on the H-11.
 -------- Original message --------
 From: Richard Cini
 Date:03/10/2016 4:09 PM (GMT-05:00)
 To: "General Discussion: On-Topic and Off-Topic Posts"
 Subject: Re: Which RT-11 for an 11/03
 If I have time tonight I'll log the session with "verbose" set on the TU58EM. Again, I'm trying the trick of booting from a TU58 emulator and an RK image with DD as the boot target (supposedly can work but maybe slow). I can see the blocks being read in but it stops and doesn't give me the sign-on banner.
 Sent from my iPhone

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