Ersatz-11 and BSD Unix

Jonathan Harston

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Jan 20, 2022, 4:24:57 PM1/20/22

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Can somebody give me a .ini file to boot BSD2-11 Unix on Ersatz-11?
I got BSD2-11 from https://skn.noip.me/pdp11/ as rp0.dsk
I can boot into it with SIMH with:
set cpu 11/70 2M nofpp
set clk 50hz
set rp1 RP06
attach rp1 rp1.dsk
boot rp1

But after an hour's fiddling I can't work out what to use for Ersatz-11.
I've got Unix5/6/7 and RT11 all working find on Ersatz-11.

Ta.
jgh

Bill Gunshannon

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Jan 20, 2022, 6:30:54 PM1/20/22

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Why don't you grab a copy of the tape and just do a fresh install
for whatever hardware you choose?

bill

Johnny Billquist

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Jan 21, 2022, 11:58:02 AM1/21/22

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What happens when you try 2.11 then? Because I don't expect there should
be any problems. And what are you setting e11 up with when booting 2.11?

Johnny

Jonathan Harston

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Jan 23, 2022, 1:17:53 PM1/23/22

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On Friday, 21 January 2022 at 16:58:02 UTC, Johnny Billquist wrote:
> What happens when you try 2.11 then? Because I don't expect there should
> be any problems. And what are you setting e11 up with when booting 2.11?

I don't want to start from scratch as my BSD2.11 image already has code on
that I've been working on.

In all cases I start with:
start C:\Apps\Emulators\Ersatz11\E11 /initfile:H:\Develop\PDP11\Unix\e11bsd2-11.ini

I've tried the ini file containing:
set cpu 45
mount dl0: H:\develop\pdp11\unix\bsd2-11.dsk
boot dl0:

All attempts end up with Ersatz displaying:
%HALT
R0/156772 R1/174400 R2/000000 R3/000000 CM=K PM=K PRIO=1
R4/100020 R5/000000 SP/000012 PC/012714 N=0 Z=1 V=1 C=1
012714 halt
E11>

Starting unix7 with the following works fine:
set cpu 45
mount dl0: H:\develop\pdp11\unix\unix_v7_rl.dsk /rl02
boot dl0:

Tim

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Jan 23, 2022, 3:50:28 PM1/23/22

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On Sunday, January 23, 2022 at 12:17:53 PM UTC-6, j...@mdfs.net wrote:
> On Friday, 21 January 2022 at 16:58:02 UTC, Johnny Billquist wrote:

> mount dl0: H:\develop\pdp11\unix\bsd2-11.dsk

What size/type of disk is this defined as? Maybe it's not big enough and something is truncated?
Or maybe it's too big? The other disk for Unix 7 seems to be an RL02. I had an issue with using
a disk image on my SCSI2SD. The image runs fine under Simh. But tries to boot on real hardware
but then dies. I believe it must have to do with how I configured the disk on the UC17. I could have
sworn it used to work. Someday I will re-sysgen a RSTS/E image and try again.

Jonathan Harston

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Jan 23, 2022, 8:12:59 PM1/23/22

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The image is 166M in size.
Booting starts up with:
xp(0,1,0)unix
Within unix, disklabel gives:
# disklabel xp1
# /dev/rxp1a:
type: SMD
disk: SMD
label: DEFAULT
flags:
bytes/sector: 512
sectors/track: 22
tracks/cylinder: 19
sectors/cylinder: 418
cylinders: 815
rpm: 3600
interleave: 1
trackskew: 0
cylinderskew: 0
headswitch: 0 # milliseconds
track-to-track seek: 0 # milliseconds
drivedata: 1

3 partitions:
# size offset fstype [fsize bsize]
a: 332310 0 2.11BSD 1024 1024 # (Cyl. 0 - 794)
b: 8360 332310 swap # (Cyl. 795 - 814)
c: 340670 0 unused 1024 1024 # (Cyl. 0 - 814)
#

Johnny Billquist

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Jan 23, 2022, 11:41:43 PM1/23/22

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This makes no sense...

You .ini file suggest that you are trying to attach something as an RL
disk. But what you are showing below is a massbus disk.

They are not the same, and the boot block and various boot information
is not the same between them. You need to attach the disk with the right
disk controller!

Johnny

Walter F.J. Müller

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Jun 8, 2022, 2:37:22 AM6/8/22

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On Thursday, January 20, 2022 at 10:24:57 PM UTC+1, j...@mdfs.net wrote:
> Can somebody give me a .ini file to boot BSD2-11 Unix on Ersatz-11?
> I got BSD2-11 from https://skn.noip.me/pdp11/ as rp0.dsk
> I can boot into it with SIMH with:
> set cpu 11/70 2M nofpp

...

Disabling the FPP with `nofpp` is not a good idea.
SimH simulates the FPP, so why not use it ?
Running without FPP is only relevant for real hardware without a functioning FPP.
BSD2.11 has a build-in FPP emulation, but that was broken. I fixed that in 2007,2009, and 2017 see
https://wfjm.github.io/blogs/211bsd/2007-01-03-patch-445.html
https://wfjm.github.io/blogs/211bsd/2009-01-04-patch-446+447.html
https://wfjm.github.io/blogs/211bsd/2017-06-06-kernel-panic-here-doc-tcsh.html

If you really want to boot with `nofpp` ensure that you use a BSD2.11 with at least patch level 447.
Some tape distributions are older than that.

Jonathan Harston

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Jul 7, 2022, 6:53:16 PM7/7/22

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Following up on this, this works for me:

set cpu 70
mount db0: H:\develop\pdp11\unix\bsd2-11.dsk /rp06
boot db0: