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3b2: Fix for clock drift when idling

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When the 3B2 simulator was set to allow idling, there was significant
clock drift related to the primary timer unit. It turns out that the
simulator was using `AIO_SET_INTERRUPT_LATENCY` and `sim_rtcn_tick_ack`
incorrectly. They are not needed with the structure of system timers in
the 3B2 architecture.
This commit is contained in:
Seth Morabito 2022-12-06 17:13:03 -08:00 • committed by Paul Koning
parent dcd3e48048
commit da6dcef801
2 changed files with 0 additions and 3 deletions
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1
3B2/3b2_stddev.c
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@ -388,7 +388,6 @@ static t_stat tod_svc(UNIT *uptr)
sim_activate_after(uptr, 1000000/CLK_TPS); sim_activate_after(uptr, 1000000/CLK_TPS);
tmr_poll = t; tmr_poll = t;
tmxr_poll = t; tmxr_poll = t;
AIO_SET_INTERRUPT_LATENCY(tmr_poll * CLK_TPS);
return SCPE_OK; return SCPE_OK;
} }

2
3B2/3b2_timer.c
View file

@ -345,8 +345,6 @@ uint32 timer_read(uint32 pa, size_t size)
of also clearing pending interrupts */ of also clearing pending interrupts */
CSRBIT(CSRCLK, FALSE); CSRBIT(CSRCLK, FALSE);
CPU_CLR_INT(INT_CLOCK); CPU_CLR_INT(INT_CLOCK);
/* Acknowledge a clock tick */
sim_rtcn_tick_ack(1, TMR_CLK);
retval = 0; retval = 0;
break; break;
default: default: