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The original SET CONSOLE SPEED=nnn was added to a allow direct wired
terminal connected to a host system serial port to be a simulator's console.
The current change generalizes all console I/O such that speed is a reliable
option for direct console connections as well as serial and telnet connections.
The simple recipe to get well behaved console output speed is:
1) call tmxr_set_console_units() in the reset routine of the console DEVICE.
2) In the code path that engages console output do something similar
to this as appropriate for the system being simulated:
void txdb_wr (int32 data)
{
tto_unit.buf = data & 0377;
tto_csr = tto_csr & ~CSR_DONE;
CLR_INT (TTO);
sim_activate (&tto_unit, tto_unit.wait);
}
3) In the output unit's service routine the console output unit's service
routine do something similar to this as appropriate for the system
being simulated:
t_stat tto_svc (UNIT *uptr)
{
int32 c;
c = sim_tt_outcvt (tto_unit.buf, TT_GET_MODE (uptr->flags));
if (c >= 0) {
t_stat r;
if ((r = sim_putchar_s (c)) != SCPE_OK) { /* output; error? */
sim_activate (uptr, uptr->wait); /* retry */
return ((r == SCPE_STALL)? SCPE_OK: r); /* !stall? report */
}
}
tto_csr = tto_csr | CSR_DONE;
if (tto_csr & CSR_IE)
SET_INT (TTO);
}
The almost all of the current simh simulators already are implemented
with logic like the above example. These will work just fine with the
newly regulated console speed.