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PDP11: Fix bug in KG11 emulation

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Reported by Reindert Voorhorst: if several bytes/words are processed
by the KG11 without intervening status/config register writes, the
wrong answer is produced.  The issue is a missing reset of the pulse
count internal register, which should be cleared by a data register
write.  The manual (DEC-11-KKGAA-B-D) has the details.
This commit is contained in:
Paul Koning 2022-02-04 08:00:07 -08:00 committed by Mark Pizzolato
parent 35503f4765
commit 34a6388114
1 changed files with 1 additions and 0 deletions
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PDP11/pdp11_kg.c
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@ -342,6 +342,7 @@ static t_stat kg_wr (int32 data, int32 PA, int32 access)
fprintf (sim_deb, ">>KG%d: wr DR %06o, data %06o, PC %06o\n",
unit, kg_unit[unit].DR, data, PC);
kg_unit[unit].SR &= ~KGSR_M_DONE;
kg_unit[unit].PULSCNT = 0;
/* In a typical device, this is normally where we would use sim_activate()
to initiate an I/O to be completed later. The KG is a little