emu: implemented a better clock; implemented repeat functionality, no knobs on panel yet

README.md

@@ -37,7 +37,8 @@ Otherwise you need SDL and pthread.
 
 The cpu (apr), console tty, paper tape and punch,
 the data control and DECtape are implemented.
-The only things missing from the cpu is the repeat key mechanism.
+The panel is missing the repeat delay knobs,
+but the functionality is implemented.
 
 ## Verilog Simulation
 
@@ -125,7 +126,7 @@ misc	nothing important
 
 ## To do
 
-- repeat and maint. switches
+- repeat and maint. switches on panel
 - improve timing
 - implement 340 display
 - do more tests

emu/Makefile

@@ -1,4 +1,4 @@
-SRC=emu.c util.c threading.c cmd.c apr.c mem.c tty.c pt.c dc.c dt.c netmem.c ../tools/pdp6common.c
+SRC=emu.c apr.c mem.c tty.c pt.c dc.c dt.c netmem.c cmd.c util.c threading.c rtc.c ../tools/pdp6common.c
 H=pdp6.h ../tools/pdp6common.h threading.h
 # clang
 #CFLAGS= -Wno-shift-op-parentheses -Wno-logical-op-parentheses \

emu/apr.c

@@ -240,6 +240,9 @@ makeapr(int argc, char *argv[])
 	t = (Task){ nil, aprcycle, apr, 1, 0 };
 	addtask(t);
 
+	apr->clkchan = chancreate(sizeof(int), 1);
+	apr->rptchan = chancreate(sizeof(int), 1);
+
 	return &apr->dev;
 }
 
@@ -3290,9 +3293,25 @@ defpulse(key_go)
 
 defpulse_(kt4)
 {
+	/* low end of ranges. unsure, but not totally off */
+	static word ranges[6] = {
+		     3400,
+		    41718,	// *12.27
+		   602407,	// *14.44
+		  6024079,	// *10
+		 60240792,	// *10
+		269878748,	// *4.48
+	};
+	static RtcMsg rpt = { 1, 0, nil, 0 };
+
 	if(apr->run && (apr->key_ex_st || apr->key_dep_st))
 		pulse(apr, &key_go, 0); 	// 5-2
-	// TODO check repeat switch
+
+	rpt.c = apr->rptchan;
+	rpt.interval = ranges[apr->speed_range];
+	/* TODO: is this just a multiplier */
+	rpt.interval *= 1 + apr->speed_set/100.0f*14.0f;
+	chansend(rtcchan, &rpt);
 }
 
 defpulse(kt3)
@@ -3381,11 +3400,11 @@ updatebus(void *bus)
 	b->c34_pulse = (b->c34_prev ^ b->c34) & b->c34;
 }
 
-#define TIMESTEP (1000.0/60.0)
-
 void
 aprstart(Apr *apr)
 {
+	static RtcMsg lineclk = { 1, 1, nil, 1000000000/60 };
+
 	int i;
 	printf("[aprstart]\n");
 
@@ -3404,8 +3423,10 @@ aprstart(Apr *apr)
 	apr->iobus.c34 = 0;
 
 	pulse(apr, &mr_pwr_clr, 100);	// random value
-	apr->lasttick = getms();
 	apr->powered = 1;
+
+	lineclk.c = apr->clkchan;
+	chansend(rtcchan, &lineclk);
 }
 
 static void
@@ -3423,21 +3444,17 @@ aprcycle(void *p)
 	}else if(!apr->powered)
 		aprstart(apr);
 
-/*
-	if(apr->pulsestepping){
-		int c;
-		while(c = getchar(), c != EOF && c != '\n')
-			if(c == 'x')
-				apr->pulsestepping = 0;
-	}
-*/
-
-	apr->tick = getms();
-	if(apr->tick-apr->lasttick >= TIMESTEP){
-		apr->lasttick = apr->lasttick+TIMESTEP;
+	int foo;
+	if(channbrecv(apr->clkchan, &foo) == 1){
+//		printf("tick\n");
 		apr->cpa_clock_flag = 1;
 		recalc_cpa_req(apr);
 	}
+	if(channbrecv(apr->rptchan, &foo) == 1){
+//		printf("rpt\n");
+		if(KEY_MANUAL)
+			pulse(apr, &kt0a, 1);
+	}
 
 	apr->iobus.c12_prev = apr->iobus.c12;
 	apr->iobus.c34_prev = apr->iobus.c34;

emu/main_panel.c

@@ -35,12 +35,6 @@ struct Element
 	int active;
 };
 
-u32
-getms(void)
-{
-	return SDL_GetTicks();
-}
-
 SDL_Surface*
 mustloadimg(const char *path)
 {
@@ -544,12 +538,12 @@ threadmain(int argc, char *argv[])
 	default:
 		usage();
 	}ARGEND;
+
 	if(debugfp = fopen(outfile, "w"), debugfp == nil){
 		fprintf(stderr, "Can't open %s\n", outfile);
 		exit(1);
 	}
 
-
 	if(SDL_Init(SDL_INIT_VIDEO) < 0)
 		err("%s", SDL_GetError());
 
@@ -638,6 +632,8 @@ threadmain(int argc, char *argv[])
 
 	extra_l = e; e += 1;
 
+	rtcchan = chancreate(sizeof(RtcMsg), 20);
+
 	dofile("init.ini");
 	apr = (Apr*)getdevice("apr");
 	tty = (Tty*)getdevice("tty");
@@ -650,6 +646,7 @@ threadmain(int argc, char *argv[])
 	addtask(t);
 	threadcreate(simthread, nil);
 	threadcreate(cmdthread, cmdchans);
+	threadcreate(rtcthread, nil);
 
 	for(;;){
 		while(SDL_PollEvent(&ev))

emu/main_serial.c

@@ -9,13 +9,6 @@
 // TODO: get rid of this
 void updatepanel(Apr *apr) {}
 
-u32
-getms(void)
-{
-	// TODO
-	return 0;
-}
-
 #define KEYPULSE(k) (apr->k && !oldapr.k)
 
 void
@@ -179,12 +172,12 @@ threadmain(int argc, char *argv[])
 	default:
 		usage();
 	}ARGEND;
+
 	if(debugfp = fopen(outfile, "w"), debugfp == nil){
 		fprintf(stderr, "Can't open %s\n", outfile);
 		exit(1);
 	}
 
-
 	dofile("init.ini");
 	apr = (Apr*)getdevice("apr");
 	ptr = (Ptr*)getdevice("ptr");

emu/pdp6.h

@@ -25,7 +25,6 @@ extern int dotrace;
 void trace(char *fmt, ...);
 void debug(char *fmt, ...);
 void err(char *fmt, ...);
-u32 getms(void);
 
 void strtolower(char *s);
 int hasinput(int fd);
@@ -39,6 +38,7 @@ void cli(FILE *f, Channel **c);
 void readcmdchan(void *p);
 void *cmdthread(void *);
 void *simthread(void *p);
+void *rtcthread(void *p);
 void dofile(const char *path);
 
 enum {
@@ -100,6 +100,16 @@ struct Task
 extern Task *tasks;
 void addtask(Task t);
 
+typedef struct RtcMsg RtcMsg;
+struct RtcMsg
+{
+	int msg;	// 1 - start; 0 - stop
+	int repeat;
+	Channel *c;
+	word interval;
+};
+extern Channel *rtcchan;
+
 typedef struct Device Device;
 struct Device
 {
@@ -352,6 +362,9 @@ struct Apr
 	bool key_ex, key_ex_nxt;
 	bool key_rd_off, key_rd_on;
 	bool key_pt_rd, key_pt_wr;
+	/* knobs */
+	int speed_range;	// 0-5
+	int speed_set;		// 1-100
 
 	/* PI */
 	u8 pio, pir, pih, pi_req;
@@ -426,11 +439,9 @@ struct Apr
 	bool fc_e_pse;
 	bool pc_set;
 
-	/* needed for the emulation */
-	double lasttick, tick;
+	Channel *clkchan, *rptchan;
 	int extpulse;
 	bool ia_inh;	// this is asserted for some time
-	int pulsestepping;
 
 	/* This could be abstracted away */
 	TPulse pulses[MAXPULSE];

emu/rtc.c

@@ -0,0 +1,163 @@
+#include "pdp6.h"
+#include <time.h>
+
+struct timespec
+timesub(struct timespec t1, struct timespec t2)
+{
+	struct timespec d;
+	d.tv_sec = t2.tv_sec - t1.tv_sec;
+	d.tv_nsec = t2.tv_nsec - t1.tv_nsec;
+	if(d.tv_nsec < 0){
+		d.tv_nsec += 1000000000;
+		d.tv_sec -= 1;
+	}
+	return d;
+}
+
+struct timespec
+timeadd(struct timespec t1, struct timespec t2)
+{
+	struct timespec s;
+	s.tv_sec = t1.tv_sec + t2.tv_sec;
+	s.tv_nsec = t1.tv_nsec + t2.tv_nsec;
+	if(s.tv_nsec >= 1000000000){
+		s.tv_nsec -= 1000000000;
+		s.tv_sec += 1;
+	}
+	return s;
+}
+
+/* is t2 after t1 */
+int
+timeafter(struct timespec t1, struct timespec t2)
+{
+	if(t1.tv_sec == t2.tv_sec)
+		return t1.tv_nsec < t2.tv_nsec;
+	return t1.tv_sec < t2.tv_sec;
+}
+
+/* is t2 before t1 */
+int
+timebefore(struct timespec t1, struct timespec t2)
+{
+	if(t1.tv_sec == t2.tv_sec)
+		return t1.tv_nsec > t2.tv_nsec;
+	return t1.tv_sec > t2.tv_sec;
+}
+
+typedef struct Clockchan Clockchan;
+struct Clockchan
+{
+	int active;
+	Channel *c;
+	struct timespec start;
+	struct timespec timeout;
+	struct timespec interval;
+	int repeat;
+	Clockchan *next;
+};
+static Clockchan *channels;
+Channel *rtcchan;
+
+static Clockchan*
+getchan(Channel *c)
+{
+	Clockchan *cc;
+	for(cc = channels; cc; cc = cc->next)
+		if(cc->c == c)
+			return cc;
+	return nil;
+}
+
+static void
+rtcstart(Channel *c, word interval, int repeat)
+{
+	Clockchan *cc;
+
+	cc = getchan(c);
+	if(cc == nil){
+		cc = malloc(sizeof(Clockchan));
+		memset(cc, 0, sizeof(Clockchan));
+		cc->next = channels;
+		channels = cc;
+	}
+
+	cc->active = 1;
+	cc->c = c;
+	clock_gettime(CLOCK_REALTIME, &cc->start);
+	cc->interval.tv_sec = interval / 1000000000;
+	cc->interval.tv_nsec = interval % 1000000000;
+	cc->timeout = timeadd(cc->start, cc->interval);
+	cc->repeat = repeat;
+}
+
+static void
+rtcstop(Channel *c)
+{
+	Clockchan *cc;
+
+	cc = getchan(c);
+	if(cc)
+		cc->active = 0;
+}
+
+void*
+rtcthread(void *p)
+{
+	struct timespec now;
+	Clockchan *cc;
+	RtcMsg msg;
+	int loss;
+
+	loss = 0;
+	for(;;){
+		clock_gettime(CLOCK_REALTIME, &now);
+
+		/* Check all channels for a timeout */
+		for(cc = channels; cc; cc = cc->next){
+			if(!cc->active || timebefore(cc->timeout, now))
+				continue;
+
+			/* I *hope* this is ok */
+			if(channbsend(cc->c, &loss) == 0)
+				;//printf("missed clock\n");
+			if(cc->repeat)
+				cc->timeout = timeadd(cc->timeout, cc->interval);
+			else
+				cc->active = 0;
+		}
+
+		if(channbrecv(rtcchan, &msg) == 1){
+			if(msg.msg == 1)
+				rtcstart(msg.c, msg.interval, msg.repeat);
+			else
+				rtcstop(msg.c);
+		}
+	}
+}
+
+
+/*
+int
+main()
+{
+	long max = 0;
+	int n = 0x7FFFFFFF;
+
+	struct timespec interval = { 0, 500000000 };
+	struct timespec timeout, now;
+
+	clock_gettime(CLOCK_REALTIME, &timeout);
+	timeout = timeadd(timeout, interval);
+
+	while(n--){
+		clock_gettime(CLOCK_REALTIME, &now);
+		if(timeafter(timeout, now)){
+			timeout = timeadd(timeout, interval);
+			printf("tick\n");		
+		}
+	}
+
+	return 0;
+}
+*/