remove old verilog code; implement shared memory for panel6; sblk output for ld6

Author: aap

README.md

@@ -1,4 +1,4 @@
-# PDP-6 Emulator and Verilog Simulation
+# PDP-6 Emulator
 
 This project aims to revive the PDP-6 (and later PDP-10)
 computers by DEC.
@@ -41,23 +41,6 @@ the data control and DECtape are implemented.
 The panel is missing the repeat delay knobs,
 but the functionality is implemented.
 
-## Verilog Simulation
-
-The verilog code is a very accurate transcription of the schematics as well.
-Since the real machine is asynchronous I had to pull some tricks to make it
-work on an FPGA.
-The real machine uses delays that are triggered by pulses and output another
-pulse after some time. Instead of pulses I use clock enables, and delays are
-implemented by a counter synchronized to the 50MHz system clock.
-
-### FPGA
-
-I'm using a DE0-Nano-SoC with has an ARM hps connected to the Cyclone V FPGA.
-On the ARM side runs fe6 (a DDT-like interface) which communicates with
-the FPGA through memory mapped IO registers.
-The quartus project is not yet part of this repo
-but the important modules are in the verilog directory.
-
 ## File tree
 NB: not up to date
 
@@ -100,9 +83,6 @@ tools/test2.s
 tools/ptdump.c	print a paper tape file in octal
 tools/dtdump.c	print dtr DECtape
 
-verilog
-verilog/...	fpga stuff
-
 code	random code for the PDP-6, mostly testing
 code/bootstrap.txt	a list of boot loaders
 code/dtboot.s		loads the first block from a DECtape

emu/util.c

@@ -2,6 +2,10 @@
 #include <string.h>
 #include <ctype.h>
 
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/mman.h>
 #include <sys/socket.h>
 #include <netinet/in.h>
 #include <netinet/tcp.h>
@@ -135,3 +139,51 @@ nodelay(int fd)
 	int flag = 1;
 	setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &flag, sizeof(flag));
 }
+
+
+void*
+createseg(const char *name, size_t sz)
+{
+	int fd;
+	void *p;
+
+	mode_t mask = umask(0);
+	fd = open(name, O_RDWR|O_CREAT, 0666);
+	umask(mask);
+	// if we try to open a /tmp file owned by another user
+	// with O_CREAT, the above will fail (even for root).
+	// so try again without O_CREAT
+	if(fd == -1)
+		fd = open(name, O_RDWR);
+	if(fd == -1) {
+		fprintf(stderr, "couldn't open file %s\n", name);
+		return NULL;
+	}
+	ftruncate(fd, sz);
+	p = mmap(NULL, sz, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
+	if(p == MAP_FAILED) {
+		fprintf(stderr, "couldn't mmap file\n");
+		return NULL;
+	}
+
+	return p;
+}
+void*
+attachseg(const char *name, size_t sz)
+{
+	int fd;
+	void *p;
+
+	fd = open(name, O_RDWR);
+	if(fd == -1) {
+		fprintf(stderr, "couldn't open file %s\n", name);
+		return NULL;
+	}
+	p = mmap(NULL, sz, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
+	if(p == MAP_FAILED) {
+		fprintf(stderr, "couldn't mmap file\n");
+		return NULL;
+	}
+
+	return p;
+}

emu/util.h

@@ -5,3 +5,6 @@ int readn(int fd, void *data, int n);
 int dial(const char *host, int port);
 void serve(int port, void (*handlecon)(int, void*), void *arg);
 void nodelay(int fd);
+
+void *createseg(const char *name, size_t sz);
+void *attachseg(const char *name, size_t sz);

panel/panel6.c

@@ -161,6 +161,7 @@ set36lights(uchar *b, Element *l)
 	setlights(b[4], l+32, 4);
 }
 
+
 uchar
 getswitches(Element *sw, int n, int state)
 {
@@ -183,6 +184,25 @@ getswitches_(Element *sw, int n, int state)
 	return b;
 }
 
+void
+setnlights(int b, Element *l, int n, int bit)
+{
+	int i;
+	for(i = 0; i < n; i++, bit >>= 1)
+		l[i].state = !!(b & bit);
+}
+
+int
+getnswitches(Element *sw, int bit, int n, int state)
+{
+	int b, i;
+	b = 0;
+	for(i = 0; i < n; i++, bit >>= 1)
+		if(sw[i].state == state)
+			b |= bit;
+	return b;
+}
+
 
 uchar
 get18switches(uchar *b, Element *sw)
@@ -472,6 +492,81 @@ servethread(void *x)
 	serve(2000, handlenetwork, nil);
 }
 
+#include "panel6.h"
+
+void*
+shmthread(void *x)
+{
+	int key = 666;
+	int id;
+	Panel6 *p;
+	int sw;
+
+	p = createseg("/tmp/pdp6_panel", sizeof(Panel6));
+	if(p == nil)
+		exit(1);
+
+	// set switches from previous state
+	setnlights(p->sw0, data_sw+18, 18, 0400000);
+	setnlights(p->sw1, data_sw, 18, 0400000);
+	setnlights(p->sw2, ma_sw, 18, 0400000);
+	misc_sw[0].state = !!(p->sw3 & SW_REPEAT);
+	misc_sw[1].state = !!(p->sw3 & SW_ADDR_STOP);
+	misc_sw[2].state = !!(p->sw3 & SW_POWER);
+	misc_sw[3].state = !!(p->sw3 & SW_MEM_DISABLE);
+
+	for(;;) {
+		p->sw0 = getnswitches(data_sw+18, 0400000, 18, 1);
+		p->sw1 = getnswitches(data_sw, 0400000, 18, 1);
+		p->sw2 = getnswitches(ma_sw, 0400000, 18, 1);
+		sw = 0;
+		if(keys[0].state == 1) sw |= KEY_START;
+		if(keys[0].state == 2) sw |= KEY_READIN;
+		if(keys[1].state == 1) sw |= KEY_INST_CONT;
+		if(keys[1].state == 2) sw |= KEY_MEM_CONT;
+		if(keys[2].state == 1) sw |= KEY_INST_STOP;
+		if(keys[2].state == 2) sw |= KEY_MEM_STOP;
+		if(keys[3].state == 1) sw |= KEY_IO_RESET;
+		if(keys[3].state == 2) sw |= KEY_EXEC;
+		if(keys[4].state == 1) sw |= KEY_DEP;
+		if(keys[4].state == 2) sw |= KEY_DEP_NXT;
+		if(keys[5].state == 1) sw |= KEY_EX;
+		if(keys[5].state == 2) sw |= KEY_EX_NXT;
+		if(misc_sw[0].state == 1) sw |= SW_REPEAT;
+		if(misc_sw[1].state == 1) sw |= SW_ADDR_STOP;
+		if(misc_sw[2].state == 1) sw |= SW_POWER;
+		if(misc_sw[3].state == 1) sw |= SW_MEM_DISABLE;
+		p->sw3 = sw;
+
+		sw = 0;
+		if(keys[6].state == 1) sw |= KEY_MOTOR_OFF;
+		if(keys[6].state == 2) sw |= KEY_MOTOR_ON;
+		if(keys[7].state == 1) sw |= KEY_PTP_FEED;
+		if(keys[7].state == 2) sw |= KEY_PTR_FEED;
+		p->sw4 = sw;
+
+		setnlights(p->lights0, mi_l+18, 18, 0400000);
+		setnlights(p->lights1, mi_l, 18, 0400000);
+		setnlights(p->lights2, ma_l, 18, 0400000);
+		setnlights(p->lights3, ir_l, 18, 0400000);
+		setnlights(p->lights4, pc_l, 18, 0400000);
+
+		misc_l[0].state = !!(p->lights5 & L5_PI_ON);
+		misc_l[1].state = !!(p->lights5 & L5_MC_STOP);
+		misc_l[2].state = !!(p->lights5 & L5_RUN);
+		misc_l[3].state = !!(p->lights5 & L5_REPEAT);
+		misc_l[4].state = !!(p->lights5 & L5_ADDR_STOP);
+		misc_l[5].state = !!(p->lights5 & L5_POWER);
+		misc_l[6].state = !!(p->lights5 & L5_MEM_DISABLE);
+		setnlights(p->lights5, pio_l, 7, 0100);
+
+		setnlights(p->lights6, pir_l, 7, 0100);
+		setnlights(p->lights6, pih_l, 7, 020000);
+
+		usleep(30);
+	}
+}
+
 void*
 openserial(void *x)
 {
@@ -677,8 +772,9 @@ main(int argc, char *argv[])
 	extra_l = e; e += 1;
 
 //	pthread_create(&comthread, nil, talki2c, nil);
-	pthread_create(&comthread, nil, servethread, nil);
+//	pthread_create(&comthread, nil, servethread, nil);
 //	pthread_create(&comthread, nil, talkserial, nil);
+	pthread_create(&comthread, nil, shmthread, nil);
 
 	for(;;){
 		while(SDL_PollEvent(&ev))
@@ -714,6 +810,7 @@ main(int argc, char *argv[])
 			drawelement(renderer, e, 1);
 
 		SDL_RenderPresent(renderer);
+		SDL_Delay(30);
 	}
 	return 0;
 }

panel/panel6.h

@@ -0,0 +1,65 @@
+
+enum {
+	// sw0 data right
+	// sw1 data left
+	// sw2 addr
+	// sw3
+	KEY_START	= 01,
+	KEY_READIN	= 02,
+	KEY_INST_CONT	= 04,
+	KEY_MEM_CONT	= 010,
+	KEY_INST_STOP	= 020,
+	KEY_MEM_STOP	= 040,
+	KEY_IO_RESET	= 0100,
+	KEY_EXEC	= 0200,
+	KEY_DEP		= 0400,
+	KEY_DEP_NXT	= 01000,
+	KEY_EX		= 02000,
+	KEY_EX_NXT	= 04000,
+
+	SW_POWER	= 0400000,
+	SW_REPEAT	= 0200000,
+	SW_MEM_DISABLE	= 0100000,
+	SW_ADDR_STOP	= 040000,
+
+	// sw4
+	KEY_MOTOR_ON	= 01,
+	KEY_MOTOR_OFF	= 02,
+	KEY_PTR_FEED	= 04,
+	KEY_PTP_FEED	= 010,
+
+	// l0	MI right
+	// l1	MI left
+	// l2	MA
+	// l3	IR
+	// l4	PC
+	// l5
+	L5_POWER	= 0400000,
+	L5_REPEAT	= 0200000,
+	L5_MEM_DISABLE	= 0100000,
+	L5_ADDR_STOP	= 0040000,
+	L5_RUN		= 0010000,
+	L5_MC_STOP	= 0004000,
+	L5_PI_ON	= 0002000,
+	// pio		000177
+	// l6
+	// pih		037600
+	// pir		000177
+};
+
+typedef struct Panel6 Panel6;
+struct Panel6
+{
+	int sw0;
+	int sw1;
+	int sw2;
+	int sw3;
+	int sw4;
+	int lights0;
+	int lights1;
+	int lights2;
+	int lights3;
+	int lights4;
+	int lights5;
+	int lights6;
+};