implemented instruction fetch

Makefile

@@ -1,5 +1,8 @@
-SRC=main.c apr.c mem.c
-CFLAGS=-Wno-shift-op-parentheses -Wno-logical-op-parentheses\
-	 -L/usr/local/lib -I/usr/local/include -lSDL -lSDL_image -lpthread
+SRC=main.c apr.c mem.c io.c
+CFLAGS= -Wno-shift-op-parentheses -Wno-logical-op-parentheses\
+        -Wno-bitwise-op-parentheses\
+        -L/usr/local/lib -I/usr/local/include -lSDL -lSDL_image -lpthread
+
+
 pdp6: $(SRC) pdp6.h
 	$(CC) $(CFLAGS) $(SRC) -o pdp6

apr.c

@@ -30,6 +30,25 @@ set_pi_cyc(bool value)
 		apr.ex_pi_sync = 1;	// 5-13
 }
 
+void
+set_pir(u8 value)
+{
+	int chan;
+	u8 req;
+	// 8-3
+	apr.pir = value;
+	apr.pi_req = 0;
+	if(apr.pi_active){
+		req = apr.pir & ~apr.pih;
+		for(chan = 0100; chan; chan >>= 1)
+			if(req & chan){
+				apr.pi_req = chan;
+				break;
+			}
+	}
+	apr.pi_rq = !!apr.pi_req;	// 8-4
+}
+
 void
 set_mc_rq(bool value)
 {
@@ -66,6 +85,7 @@ set_mc_rd(bool value)
 void
 set_key_rim_sbr(bool value)
 {
+	// not sure if this is correct
 	apr.key_rim_sbr = value | apr.sw_rim_maint;	// 5-2
 }
 
@@ -77,12 +97,12 @@ calcaddr(void)
 
 	// 5-13
 	apr.ex_inh_rel = !apr.ex_user || apr.ex_pi_sync ||
-	                 (apr.ma&0777760) == 0 || apr.ex_ill_op;
+	                 (apr.ma & 0777760) == 0 || apr.ex_ill_op;
 	// 7-4
 	ma18_25 = apr.ma>>10 & 0377;
 	ma_ok = ma18_25 <= apr.pr;
 	// 7-2
-	ma_fmc_select = !apr.key_rim_sbr && (apr.ma&0777760) == 0;
+	ma_fmc_select = !apr.key_rim_sbr && (apr.ma & 0777760) == 0;
 	// 7-5
 	apr.rla = ma18_25;
 	if(!apr.ex_inh_rel)
@@ -101,15 +121,19 @@ calcaddr(void)
 }
 
 pulse(kt4);
+pulse(it1);
+pulse(at1);
+pulse(iat0);
 pulse(mc_wr_rs);
+pulse(mc_rd_rq_pulse);
 
-// TODO: find PI REQ, A LONG
+// TODO: find A LONG
 
 pulse(pi_reset){
 	printf("PI RESET\n");
 	apr.pi_active = 0;	// 8-4
 	apr.pih = 0;		// 8-4
-	apr.pir = 0;		// 8-4
+	set_pir(0);		// 8-4
 	apr.pio = 0;		// 8-3
 	return NULL;
 }
@@ -141,10 +165,13 @@ pulse(mr_clr){
 	set_ex_mode_sync(0);	// 5-13
 	apr.ex_uuo_sync = 0;	// 5-13
 	apr.ex_pi_sync = 0;	// 5-13
+
+	apr.a_long = 0;		// nowhere to be found :(
 	// TODO: MP CLR, DS CLR
 
 	/* sbr flip-flops */
 	apr.key_rd_wr = 0;	// 5-2
+	apr.if1a = 0;		// 5-3
 	mc_rst1_ret = NULL;
 	return NULL;
 }
@@ -193,9 +220,87 @@ pulse(st7){
 	return NULL;
 }
 
+/*
+ * Priority Interrupt
+ */
+
+pulse(pir_stb){
+	printf("PIR STB\n");
+	set_pir(apr.pir | apr.pio & iobus1);	// 8-3
+	return NULL;
+}
+
+pulse(pi_sync){
+	printf("PI SYNC\n");
+	if(!apr.pi_cyc)
+		pir_stb();
+	// 5-3
+	if(apr.pi_rq && !apr.pi_cyc)
+		return iat0;
+	// TODO: IA INH/AT INH
+	if(apr.if1a)
+		return it1;
+	return at1;
+}
+
+/*
+ * Address
+ */
+
+pulse(at1){
+	printf("AT1\n");
+	return NULL;
+}
+
+pulse(at0){
+	printf("AT0\n");
+	return NULL;
+}
+
+/*
+ * Instruction
+ */
+
+pulse(iat0){
+	printf("IAT0\n");
+	mr_clr();
+	set_pi_cyc(1);
+	return it1;
+}
+
 pulse(it1a){
 	printf("IT1A\n");
-	return NULL;
+	apr.if1a = 0;
+	apr.ir |= (apr.mb & 0777740000000) >> 18;	// 5-7
+	if(apr.ma & 0777760)
+		set_key_rim_sbr(0);	// 5-2
+	return at0;
+}
+
+pulse(it1){
+	printf("IT1\n");
+	hword n;
+	u8 r;
+	if(apr.pi_cyc){
+		// 7-3
+		r = apr.pi_req;
+		for(n = 7; !(r & 1); n--, r >>= 1);
+		apr.ma = 040 | n<<1;
+	}else
+		apr.ma = apr.pc;	// 7-3
+	if(apr.pi_ov)
+		apr.ma = (apr.ma+1)&0777777;	// 7-3
+	apr.if1a = 1;
+	mc_rst1_ret = it1a;
+	return mc_rd_rq_pulse;
+}
+
+pulse(it0){
+	printf("IT0\n");
+	apr.ma = 0;
+	mr_clr();
+	apr.if1a = 1;		// 5-3
+	return pi_sync;
 }
 
 /*
@@ -359,7 +464,7 @@ pulse(key_go){
 	apr.key_dep_st = 0;
 	apr.key_ex_sync = 0;
 	apr.key_dep_sync = 0;
-	return NULL;
+	return it0;
 }
 
 pulse(kt4){

main.c

@@ -353,6 +353,8 @@ Light ind_lights[] = {
 	{ lampsurf, { 407, 127, 14, 22 }, 0 },
 	{ lampsurf, { 407, 144, 14, 22 }, 0 },
 	{ lampsurf, { 407, 161, 14, 22 }, 0 },
+	/* sbr flip-flops */
+	{ lampsurf, {  99,  42, 14, 22 }, 0 },
 };
 Light extra_lights[] = {
 	/* MEMBUS */
@@ -828,12 +830,13 @@ error:
 		ff_lght[31].state = apr.cpa_pia35;
 		ff_lght[32].state = apr.pi_ov;
 		ff_lght[33].state = apr.pi_cyc;
-		ff_lght[34].state = apr.pi_req;
+		ff_lght[34].state = apr.pi_rq;
 		ff_lght[35].state = apr.iot_go;
 		ff_lght[36].state = apr.a_long;
 		ff_lght[37].state = apr.ma == apr.mas;
 		ff_lght[38].state = apr.uuo_f1;
 		ff_lght[39].state = apr.cpa_pdl_ov;
+		ff_lght[40].state = apr.if1a;
 
 		setlights(membus0, membus_lght, 36);
 		setlights(apr.pr, pr_lght, 8);

mem

@@ -1,5 +1,4 @@
-1234
-4321
+201040001234
 0
 0
 0

pdp6.h

@@ -22,10 +22,9 @@ struct Apr {
 	word mb;
 	word ar;
 	word mq;
-	u8 pio, pir, pih;
 	u16 sc, fe;
 	u8 pr, rlr, rla;
-	bool run, pi_active;
+	bool run;
 	bool sw_addr_stop, sw_repeat, sw_mem_disable, sw_power;
 	bool sw_rim_maint;
 	/* keys */
@@ -38,10 +37,14 @@ struct Apr {
 	bool key_rd_off, key_rd_on;
 	bool key_pt_rd, key_pt_wr;
 
+	/* PI */
+	u8 pio, pir, pih, pi_req;
+	bool pi_active;
+	bool pi_ov, pi_cyc, pi_rq;
+
 	/* flip-flops */
 	bool ex_mode_sync, ex_uuo_sync, ex_pi_sync, ex_ill_op, ex_user;
 	bool pc_chg_flag, ar_ov_flag, ar_cry0_flag, ar_cry1_flag;
-	bool pi_ov, pi_cyc, pi_req;
 
 	bool key_ex_st, key_ex_sync;
 	bool key_dep_st, key_dep_sync;
@@ -59,6 +62,7 @@ struct Apr {
 	bool iot_go, a_long, uuo_f1;
 
 	/* sbr flip-flops */
+	bool if1a;
 	bool chf7;
 
 	/* temporaries */
@@ -93,3 +97,5 @@ enum {
 	MEMBUS_MAI_ADDR_ACK = 0400000000000,
 };
 extern word membus0, membus1;
+
+extern word iobus0, iobus1;