/* pdp8_clk.c: PDP-8 real-time clock simulator | |
Copyright (c) 1993-2012, Robert M Supnik | |
Permission is hereby granted, free of charge, to any person obtaining a | |
copy of this software and associated documentation files (the "Software"), | |
to deal in the Software without restriction, including without limitation | |
the rights to use, copy, modify, merge, publish, distribute, sublicense, | |
and/or sell copies of the Software, and to permit persons to whom the | |
Software is furnished to do so, subject to the following conditions: | |
The above copyright notice and this permission notice shall be included in | |
all copies or substantial portions of the Software. | |
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | |
ROBERT M SUPNIK BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER | |
IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN | |
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. | |
Except as contained in this notice, the name of Robert M Supnik shall not be | |
used in advertising or otherwise to promote the sale, use or other dealings | |
in this Software without prior written authorization from Robert M Supnik. | |
clk real time clock | |
18-Apr-12 RMS Added clock coscheduling | |
18-Jun-07 RMS Added UNIT_IDLE flag | |
01-Mar-03 RMS Aded SET/SHOW CLK FREQ support | |
04-Oct-02 RMS Added DIB, device number support | |
30-Dec-01 RMS Removed for generalized timers | |
05-Sep-01 RMS Added terminal multiplexor support | |
17-Jul-01 RMS Moved function prototype | |
05-Mar-01 RMS Added clock calibration support | |
Note: includes the IOT's for both the PDP-8/E and PDP-8/A clocks | |
*/ | |
#include "pdp8_defs.h" | |
extern int32 int_req, int_enable, dev_done, stop_inst; | |
int32 clk_tps = 60; /* ticks/second */ | |
int32 tmxr_poll = 16000; /* term mux poll */ | |
int32 clk (int32 IR, int32 AC); | |
t_stat clk_svc (UNIT *uptr); | |
t_stat clk_reset (DEVICE *dptr); | |
t_stat clk_set_freq (UNIT *uptr, int32 val, CONST char *cptr, void *desc); | |
t_stat clk_show_freq (FILE *st, UNIT *uptr, int32 val, CONST void *desc); | |
/* CLK data structures | |
clk_dev CLK device descriptor | |
clk_unit CLK unit descriptor | |
clk_reg CLK register list | |
*/ | |
DIB clk_dib = { DEV_CLK, 1, { &clk } }; | |
UNIT clk_unit = { UDATA (&clk_svc, UNIT_IDLE, 0), 16000 }; | |
REG clk_reg[] = { | |
{ FLDATAD (DONE, dev_done, INT_V_CLK, "device done flag") }, | |
{ FLDATAD (ENABLE, int_enable, INT_V_CLK, "interrupt enable flag") }, | |
{ FLDATAD (INT, int_req, INT_V_CLK, "interrupt pending flag") }, | |
{ DRDATAD (TIME, clk_unit.wait, 24, "clock interval"), REG_NZ + PV_LEFT }, | |
{ DRDATA (TPS, clk_tps, 8), PV_LEFT + REG_HRO }, | |
{ NULL } | |
}; | |
MTAB clk_mod[] = { | |
{ MTAB_XTD|MTAB_VDV, 50, NULL, "50HZ", | |
&clk_set_freq, NULL, NULL }, | |
{ MTAB_XTD|MTAB_VDV, 60, NULL, "60HZ", | |
&clk_set_freq, NULL, NULL }, | |
{ MTAB_XTD|MTAB_VDV, 0, "FREQUENCY", NULL, | |
NULL, &clk_show_freq, NULL }, | |
{ MTAB_XTD|MTAB_VDV, 0, "DEVNO", NULL, NULL, &show_dev }, | |
{ 0 } | |
}; | |
DEVICE clk_dev = { | |
"CLK", &clk_unit, clk_reg, clk_mod, | |
1, 0, 0, 0, 0, 0, | |
NULL, NULL, &clk_reset, | |
NULL, NULL, NULL, | |
&clk_dib, 0 | |
}; | |
/* IOT routine | |
IOT's 6131-6133 are the PDP-8/E clock | |
IOT's 6135-6137 are the PDP-8/A clock | |
*/ | |
int32 clk (int32 IR, int32 AC) | |
{ | |
switch (IR & 07) { /* decode IR<9:11> */ | |
case 1: /* CLEI */ | |
int_enable = int_enable | INT_CLK; /* enable clk ints */ | |
int_req = INT_UPDATE; /* update interrupts */ | |
return AC; | |
case 2: /* CLDI */ | |
int_enable = int_enable & ~INT_CLK; /* disable clk ints */ | |
int_req = int_req & ~INT_CLK; /* update interrupts */ | |
return AC; | |
case 3: /* CLSC */ | |
if (dev_done & INT_CLK) { /* flag set? */ | |
dev_done = dev_done & ~INT_CLK; /* clear flag */ | |
int_req = int_req & ~INT_CLK; /* clear int req */ | |
return IOT_SKP + AC; | |
} | |
return AC; | |
case 5: /* CLLE */ | |
if (AC & 1) /* test AC<11> */ | |
int_enable = int_enable | INT_CLK; | |
else int_enable = int_enable & ~INT_CLK; | |
int_req = INT_UPDATE; /* update interrupts */ | |
return AC; | |
case 6: /* CLCL */ | |
dev_done = dev_done & ~INT_CLK; /* clear flag */ | |
int_req = int_req & ~INT_CLK; /* clear int req */ | |
return AC; | |
case 7: /* CLSK */ | |
return (dev_done & INT_CLK)? IOT_SKP + AC: AC; | |
default: | |
return (stop_inst << IOT_V_REASON) + AC; | |
} /* end switch */ | |
} | |
/* Unit service */ | |
t_stat clk_svc (UNIT *uptr) | |
{ | |
dev_done = dev_done | INT_CLK; /* set done */ | |
int_req = INT_UPDATE; /* update interrupts */ | |
tmxr_poll = sim_rtcn_calb (clk_tps, TMR_CLK); /* calibrate clock */ | |
sim_activate_after (uptr, 1000000/clk_tps); /* reactivate unit */ | |
return SCPE_OK; | |
} | |
/* Reset routine */ | |
t_stat clk_reset (DEVICE *dptr) | |
{ | |
dev_done = dev_done & ~INT_CLK; /* clear done, int */ | |
int_req = int_req & ~INT_CLK; | |
int_enable = int_enable & ~INT_CLK; /* clear enable */ | |
if (!sim_is_running) { /* RESET (not CAF)? */ | |
tmxr_poll = sim_rtcn_init_unit (&clk_unit, clk_unit.wait, TMR_CLK);/* init 100Hz timer */ | |
sim_activate_after (&clk_unit, 1000000/clk_tps); /* activate 100Hz unit */ | |
} | |
return SCPE_OK; | |
} | |
/* Set frequency */ | |
t_stat clk_set_freq (UNIT *uptr, int32 val, CONST char *cptr, void *desc) | |
{ | |
if (cptr) | |
return SCPE_ARG; | |
if ((val != 50) && (val != 60)) | |
return SCPE_IERR; | |
clk_tps = val; | |
return SCPE_OK; | |
} | |
/* Show frequency */ | |
t_stat clk_show_freq (FILE *st, UNIT *uptr, int32 val, CONST void *desc) | |
{ | |
fprintf (st, (clk_tps == 50)? "50Hz": "60Hz"); | |
return SCPE_OK; | |
} |