Re: KA630: how does console I/O actually work?

I do hope someone can help you... your issue reminds me of something I
encountered with both open-simh and "classic" simh.  You appear to make
further progress on your second boot than either of them, if I am
understanding the issue you are discussing.

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MicroVAX 3900 simulator Open SIMH V4.1-0 Current        simh git commit id: d4f85d01

KA655X-B V5.3, VMB 2.7
Performing normal system tests.
40..39..38..37..36..35..34..33..32..31..30..29..28..27..26..25..
24..23..22..21..20..19..18..17..16..15..14..13..12..11..10..09..
08..07..06..05..04..03..
Tests completed.

>>>boot dua0
(BOOT/R5:0 DUA0

  2..
-DUA0
  1..0..

>> NetBSD/vax boot [1.12 (Sun Nov  5 18:30:08 UTC 2023)] <<

[   1.0000000] NetBSD 10.0_RC1 (GENERIC) #0: Sun Nov  5 18:30:08 UTC 2023

NetBSD/vax (open-sim) (constty)

[  58.1000700] syncing disks... done
[  58.1200700] unmounting file systems...
[  58.6200700] unmounting done

HALT instruction, PC: 8001542C (RET)
sim> boot dua0

Invalid argument, PC: 8001542C (RET)
sim>
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VAX simulator V3.12-4

KA655X-B V5.3, VMB 2.7
Performing normal system tests.
40..39..38..37..36..35..34..33..32..31..30..29..28..27..26..25..
24..23..22..21..20..19..18..17..16..15..14..13..12..11..10..09..
08..07..06..05..04..03..
Tests completed.

>>>boot dua0
(BOOT/R5:0 DUA0

  2..
-DUA0
  1..0..

>> NetBSD/vax boot [1.12 (Wed Nov 29 12:36:24 UTC 2023)] <<

[   1.0000000] NetBSD 10.0_RC1 (GENERIC) #0: Wed Nov 29 12:36:24 UTC 2023

NetBSD/vax (sim3vax10) (constty)

[  52.5000030] syncing disks... done
[  52.5100030] unmounting file systems...
[  52.9000030] unmounting done

HALT instruction, PC: 8001542C (RET)
sim> boot dua0
Non-existent device
sim>
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