Add emu_6800_alt, and fairly simple tests based on Altair 6800 BASIC

diff --git a/.gitignore b/.gitignore
index e5ab023..e8b5b2c 100644 (file)
--- a/.gitignore
+++ b/.gitignore
@@ -2,5 +2,7 @@
 *.o
 /emu_65c02
 /emu_65c02_alt
+/emu_6800
+/emu_6800_alt
 /emu_z80
 /emu_z80_alt

diff --git a/.gitmodules b/.gitmodules
index 06f6c19..df13f4e 100644 (file)
--- a/.gitmodules
+++ b/.gitmodules
@@ -10,3 +10,6 @@
 [submodule "ZEXALL"]
        path = ZEXALL
        url = https://github.com/nickd4/ZEXALL.git
+[submodule "sim68xx"]
+       path = sim68xx
+       url = https://github.com/nickd4/sim68xx.git

diff --git a/Makefile b/Makefile
index 38482dd..7f2316d 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,8 @@
 BIN2HEX=bin2hex.py
 
 CFLAGS=-g -Og -Wall -Wno-attributes -Wno-unused-function
+ALT_65C02_CFLAGS=-DALT_BACKEND=1 -DVR_6502_EMU_STATIC=1
+ALT_6800_CFLAGS=-DALT_BACKEND=1 -DUSE_PROTOTYPES -DM6800 -Isim68xx/inc/arch/m6800 -Isim68xx/inc/arch/m68xx -Isim68xx/inc/base
 
 .PHONY: all
 all: \
@@ -8,11 +10,14 @@ emu_65c02 \
 emu_65c02_alt \
 6502_functional_test.ihx \
 65C02_extended_opcodes_test.ihx \
+emu_6800_alt \
 emu_z80 \
 emu_z80_alt \
 zexall.ihx \
 zexdoc.ihx
+#emu_6800
 
+# 65C02
 emu_65c02: emu_65c02.o cpu_65c02.o
        ${CC} ${CFLAGS} -o $@ $^
 
@@ -24,10 +29,10 @@ emu_65c02_alt: emu_65c02_alt.o vrEmu6502.o
        ${CC} ${CFLAGS} -o $@ $^
 
 emu_65c02_alt.o: emu_65c02.c vrEmu6502/src/vrEmu6502.h
-       ${CC} ${CFLAGS} -DALT_BACKEND=1 -DVR_6502_EMU_STATIC=1 -o $@ -c $<
+       ${CC} ${CFLAGS} ${ALT_65C02_CFLAGS} -o $@ -c $<
 
 vrEmu6502.o: vrEmu6502/src/vrEmu6502.c vrEmu6502/src/vrEmu6502.h
-       ${CC} ${CFLAGS} -DVR_6502_EMU_STATIC=1 -c $<
+       ${CC} ${CFLAGS} ${ALT_65C02_CFLAGS} -c $<
 
 6502_functional_test.ihx: \
 6502_65C02_functional_tests/bin_files/6502_functional_test.bin
@@ -41,6 +46,61 @@ vrEmu6502.o: vrEmu6502/src/vrEmu6502.c vrEmu6502/src/vrEmu6502.h
        ./entry_point.py 0x400 __temp__.ihx $@
        rm __temp__.ihx
 
+# 6800
+emu_6800: emu_6800.o cpu_6800.o
+       ${CC} ${CFLAGS} -o $@ $^
+
+emu_6800.o: cpu_6800.h
+
+cpu_6800.o: cpu_6800.h
+
+emu_6800_alt: \
+emu_6800_alt.o \
+m6800_callstac.o \
+m6800_cpu.o \
+m6800_error.o \
+m6800_instr.o \
+m6800_reg.o \
+m6800_symtab.o \
+m6800_opfunc.o \
+m6800_optab.o
+       ${CC} ${CFLAGS} -o $@ $^
+#m6800_alu.o
+
+emu_6800_alt.o: \
+emu_6800.c \
+sim68xx/inc/arch/m68xx/instr.h \
+sim68xx/inc/arch/m68xx/reg.h
+       ${CC} ${CFLAGS} ${ALT_6800_CFLAGS} -o $@ -c $<
+
+m6800_alu.o: sim68xx/src/arch/m68xx/alu.c
+       ${CC} ${CFLAGS} ${ALT_6800_CFLAGS} -o $@ -c $<
+
+m6800_callstac.o: sim68xx/src/base/callstac.c
+       ${CC} ${CFLAGS} ${ALT_6800_CFLAGS} -o $@ -c $<
+
+m6800_cpu.o: sim68xx/src/base/cpu.c
+       ${CC} ${CFLAGS} ${ALT_6800_CFLAGS} -o $@ -c $<
+
+m6800_error.o: sim68xx/src/base/error.c
+       ${CC} ${CFLAGS} ${ALT_6800_CFLAGS} -o $@ -c $<
+
+m6800_instr.o: sim68xx/src/arch/m6800/instr.c
+       ${CC} ${CFLAGS} ${ALT_6800_CFLAGS} -o $@ -c $<
+
+m6800_reg.o: sim68xx/src/arch/m68xx/reg.c
+       ${CC} ${CFLAGS} ${ALT_6800_CFLAGS} -o $@ -c $<
+
+m6800_symtab.o: sim68xx/src/base/symtab.c
+       ${CC} ${CFLAGS} ${ALT_6800_CFLAGS} -o $@ -c $<
+
+m6800_opfunc.o: sim68xx/src/arch/m68xx/opfunc.c
+       ${CC} ${CFLAGS} ${ALT_6800_CFLAGS} -o $@ -c $<
+
+m6800_optab.o: sim68xx/src/arch/m6800/optab.c
+       ${CC} ${CFLAGS} ${ALT_6800_CFLAGS} -o $@ -c $<
+
+# Z80
 emu_z80: emu_z80.o cpu_z80.o
        ${CC} ${CFLAGS} -o $@ $^
 

diff --git a/basic_6800.s19 b/basic_6800.s19
new file mode 100644 (file)
index 0000000..27cda4d
--- /dev/null
+++ b/basic_6800.s19
@@ -0,0 +1,480 @@
+* see https://gitlab.com/retroabandon/altair-680-basic.git
+*
+* nick@jane:~/src/sim68xx/src/boards$ ./sim6800 basic.s19
+* Couldn't open symbol file
+* PC=ffd8 A:B=0000 X=0000 SP=0000 CCR=d0(11hInzvc)     [0]
+* ffd8 8e 00 f3        lds  #00f3
+* 
+* >g
+* ffd8: Running...
+* 
+* .J 0000
+* MEMORY SIZE? 32768
+* TERMINAL WIDTH? 80
+* WANT SIN-COS-TAN-ATN? Y
+* 
+* 26330 BYTES FREE
+* 
+* MITS ALTAIR 680 BASIC VERSION 1.1 REV 3.2
+* COPYRIGHT 1976 BY MITS INC.
+* 
+* OK
+
+ALTAIR BASIC for 6800 
+May 20, 2002
+MITS-RAW.BIN      
+
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+S9
+ ALTAIR 680B PROM MONITOR
+ ACIA VERSION 1.0
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+S9

diff --git a/basic_test.txt b/basic_test.txt
new file mode 100644 (file)
index 0000000..6a007bd
--- /dev/null
+++ b/basic_test.txt
@@ -0,0 +1,61 @@
+J0000
+80
+Y
+10 PRINT "HELLO"
+20 REM P9=X9^Y9 === GOSUB 60030
+30 X9=.3:Y9=.7:GOSUB 60030:PRINT .3^.7,P9
+40 REM L9=LOG(X9) === GOSUB 60090
+50 X9=.4:GOSUB 60090:PRINT LOG(.4),L9
+60 REM E9=EXP(X9) === GOSUB 60160
+70 X9=.5:GOSUB 60160:PRINT EXP(.5),E9
+80 REM C9=COS(X9) === GOSUB 60240
+90 X9=.6:GOSUB 60240:PRINT COS(.6),C9
+100 REM T9=TAN(X9) === GOSUB 60280
+110 X9=.7:GOSUB 60280:PRINT TAN(.7),T9
+120 REM A9=ATN(X9) === GOSUB 60310
+130 X9=.8:GOSUB 60310:PRINT ATN(.8),A9
+140 END
+60000 REM EXPONENTIATI0N: P9=X9^Y9
+60010 REM NEED: EXP, LOG
+60020 REM VARIABLES USED: A9,B9,C9,E9,L9,P9,X9,Y9
+60030 P9=1 : E9=0 : IF Y9=0 THEN RETURN
+60040 IF X9<0 THEN IF INT(Y9)=Y9 THEN P9=1-2*Y9+4*INT(Y9/2) : X9=-X9
+60050 IF X9<>0 THEN GOSUB 60090 : X9=Y9*L9 : GOSUB 60160
+60060 P9=P9*E9 : RETURN
+60070 REM NATURAL LOGARITHM: L9=LOG(X9)
+60080 REM VARIABLES USED: A9,B9,C9,E9,L9,X9
+60090 E9=0 : IF X9<=0 THEN PRINT "LOG FC ERROR"; : ST0P
+60095 A9=1 : B9=2 : C9=.5 : REM THIS WILL SPEED UP THE FOLLOWING
+60100 IF X9>=A9 THEN X9=C9*X9 : E9=E9+A9 : GOTO 60100
+60110 IF X9<C9 THEN X9=B9*X9 : E9=E9-A9 : GOTO 60110
+60120 X9=(X9-.707107)/(X9+.707107) : L9=X9*X9
+60130 L9=(((.598979*L9+.961471)*L9+2.88539)*X9+E9-.5)*.693147
+60135 RETURN
+60190 REM EXPONENTIAL: E9=EXP(X9)
+60150 REM VARIABLES USED: A9,E9,L9,X9
+60160 L9=INT(1.4427*X9)+1 : IF L9<1E7 THEN 60180
+60170 IF X9>0 THEN PRINT "EXP OV ERR0R"; : STOP
+60175 E9=0 : RETURN
+60180 E9=.693147*L9-X9 : A9=1.32988E-3-1.41316E-4*E9
+60190 A9=((A9*E9-8.30136E-3)*E9+4.16574E-2)*E9
+60195 E9=(((A9-.166665)*E9+.5)*E9-1)*E9+1 : A9=2
+60197 IF L9<=0 THEN A9=.5 : L9=-L9 : IF L9=0 THEN RETURN
+60200 FOR X9=1 TO L9 : E9=A9*E9 : NEXT X9 : RETURN
+60210 REM COSINE: C9=COS(X9)
+60220 REM N.B. SIN MUST BE RETAINED AT LOAD-TIME
+60230 REM VARIABLES USED: C9,X9
+60240 C9=SIN(X9+1.5708) : RETURN
+60250 REM TANGENT: T9=TAN(X9)
+60260 REM NEEDS COS. (SIN NUST BE RETAINED AT LOAD-TIME)
+60270 REM VARIABLES USED: C9,T9,X9
+60280 GOSUB 60240 : T9=SIN(X9)/C9 : RETURN
+60290 REM ARCTANGENT: A9=ATN(X9)
+60300 REM VARIABLES USED: A9,B9,C9,T9,X9
+60310 T9=SGN(X9): X9=ABS(X9): C9=0 : IF X9>1 THEN C9=1 : X9=1/X9
+60320 A9=X9*X9 : B9=((2.86623E-3*A9-1.61657E-2)*A9+4.29096E-2)*A9
+60330 B9=((((B9-7.5289E-2)*A9+.106563)*A9-.142089)*A9+.199936)*A9
+60340 A9=((B9-.333332)*A9+1)*X9 : IF C9=1 THEN A9=1.5708-A9
+60350 A9=T9*A9 : RETURN
+RUN
+                                                                                                                                                                                                
+PRINT "DONE"

diff --git a/doc/BASIC Manual 75.pdf b/doc/BASIC Manual 75.pdf
new file mode 100644 (file)
index 0000000..668d0af
Binary files /dev/null and b/doc/BASIC Manual 75.pdf differ

diff --git a/doc/Undocumented Flags · hoglet67_Z80Decoder Wiki.pdf b/doc/Undocumented Flags · hoglet67_Z80Decoder Wiki.pdf
new file mode 100644 (file)
index 0000000..d34ea65
Binary files /dev/null and "b/doc/Undocumented Flags \302\267 hoglet67_Z80Decoder Wiki.pdf" differ

diff --git a/doc/z80-documented.pdf b/doc/z80-documented.pdf
new file mode 100644 (file)
index 0000000..52be048
Binary files /dev/null and b/doc/z80-documented.pdf differ

diff --git a/emu_6800.c b/emu_6800.c
new file mode 100644 (file)
index 0000000..02b40b7
--- /dev/null
+++ b/emu_6800.c
@@ -0,0 +1,244 @@
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#if ALT_BACKEND
+#include "sim68xx/inc/base/cpu.h"
+#include "sim68xx/inc/arch/m68xx/instr.h"
+#include "sim68xx/inc/arch/m68xx/reg.h"
+#else
+#include "cpu_6800.h"
+#endif
+
+#define REG_TRACE 0
+#define MEM_TRACE 0
+
+#define MEM_SIZE 0x10000
+uint8_t mem[MEM_SIZE];
+
+void load_s19(char *name) {
+  FILE *fp = fopen(name, "r");
+  if (fp == NULL) {
+    perror(name);
+    exit(EXIT_FAILURE);
+  }
+
+  char line[0x100];
+  while (fgets(line, 0x100, fp)) {
+    for (char *p = line; *p; ++p)
+      if (*p == '\n') {
+        *p = 0;
+        break;
+      }
+
+    // allow comments and concatenation
+    if (line[0] != 'S' || line[1] != '1')
+      continue;
+
+    uint8_t buf[0x7f];
+    int len;
+    for (len = 0; len < 0x7f; ++len) {
+      char *p = line + 2 + len * 2;
+      if (*p == 0)
+        break;
+      if (*p == '\n') {
+        *p = 0;
+        break;
+      }
+      uint8_t c = p[2];
+      p[2] = 0;
+
+      char *q;
+      buf[len] = (uint8_t)strtol(p, &q, 16);
+      p[2] = c;
+      if (q != p + 2) {
+        fprintf(stderr, "not hex byte: %s\n", p);
+        exit(EXIT_FAILURE);
+      }
+    }
+
+    if (len < 4) {
+      fprintf(stderr, "too short: %s\n", line);
+      exit(EXIT_FAILURE);
+    }
+
+    uint8_t checksum = 0;
+    for (int i = 0; i < len; ++i)
+      checksum += buf[i];
+    if (checksum != 0xff) {
+      checksum -= 0xff + buf[len - 1];
+      fprintf(
+        stderr,
+        "checksum %02x, should be %02x\n",
+        checksum,
+        buf[len - 1]
+      );
+      exit(EXIT_FAILURE);
+    }
+
+    if (len != buf[0] + 1) {
+      fprintf(stderr, "incorrect length: %s\n", line);
+      exit(EXIT_FAILURE);
+    }
+    len -= 4;
+
+    int addr = (buf[1] << 8) | buf[2], end_addr;
+    end_addr = addr + len;
+    if (end_addr < addr || end_addr > MEM_SIZE) {
+      fprintf(stderr, "invalid load range: [0x%x, 0x%x)\n", addr, end_addr);
+      exit(EXIT_FAILURE);
+    }
+    memcpy(mem + addr, buf + 3, len);
+  }
+
+  fclose(fp);
+}
+
+int read_byte(void *context, int addr) {
+  int data;
+  switch (addr) {
+  case 0xf001:
+    data = getchar();
+    switch (data) {
+    case '\n':
+      data = '\r';
+      break;
+    case 0x7f:
+      data = '\b';
+      break;
+    case EOF:
+      exit(EXIT_SUCCESS);
+      break;
+    }
+    break;
+  default:
+    data = mem[addr];
+    break;
+  }
+#if MEM_TRACE
+  fprintf(stderr, "addr=%04x rd=%02x\n", addr, data);
+#endif
+  return data;
+}
+
+void write_byte(void *context, int addr, int data) {
+#if MEM_TRACE
+  fprintf(stderr, "addr=%04x wr=%02x\n", addr, data);
+#endif
+  switch (addr) {
+  case 0xf000:
+    break;
+  case 0xf001:
+    data &= 0x7f;
+    switch (data) {
+    case '\r':
+      putchar('\n');
+      break;
+    case '\n':
+      break;
+    default:
+      putchar(data);
+      break;
+    }
+    break;
+  default:
+    mem[addr] = data;
+  }
+}
+
+#if ALT_BACKEND
+int nerrors;
+
+u_char mem_getb(u_int addr) {
+  return read_byte(NULL, addr);
+}
+
+u_int mem_getw(u_int addr) {
+  /* Make sure hi byte is accessed first */
+  u_char hi = mem_getb(addr);
+  u_char lo = mem_getb(addr + 1);
+  return (hi << 8) | lo;
+}
+
+void mem_putb(u_int addr, u_char value) {
+  write_byte(NULL, addr, value);
+}
+
+void mem_putw(u_int addr, u_int value) {
+  mem_putb(addr, value >> 8);          /* hi byte */
+  mem_putb(addr + 1, value & 0xFF);    /* lo byte */
+}
+#endif
+
+int main(int argc, char **argv) {
+  if (argc < 2) {
+    printf("usage: %s image.s19\n", argv[0]);
+    exit(EXIT_FAILURE);
+  }
+  load_s19(argv[1]);
+
+  mem[0xf000] = 3; // bit 0 = rdrf, bit 1 = tdre
+
+#if ALT_BACKEND
+  cpu_reset();
+
+  while (true) {
+#if REG_TRACE
+    fprintf(
+      stderr,
+      "pc=%04x d=%04x ix=%02x sp=%04x ccr=%02x hf=%d if=%d nf=%d zf=%d vf=%d cf=%d\n",
+      regs.pc,
+      (regs.accd.a << 8) | regs.accd.b,
+      regs.ix,
+      regs.sp,
+      regs.ccr | 0xc0,
+      (regs.ccr >> 5) & 1,
+      (regs.ccr >> 4) & 1,
+      (regs.ccr >> 3) & 1,
+      (regs.ccr >> 2) & 1,
+      (regs.ccr >> 1) & 1,
+      regs.ccr & 1
+    );
+#endif
+
+    instr_exec();
+  }
+#else
+  struct cpu_6800 cpu;
+  cpu_6800_init(&cpu, read_byte, NULL, write_byte, NULL);
+  cpu_6800_reset(&cpu);
+  cpu.regs.word.pc = entry_point;
+  cpu.regs.byte.s = 0xff;
+
+  while (true) {
+#if REG_TRACE
+    fprintf(
+      stderr,
+      "pc=%04x a=%02x x=%02x y=%02x s=%02x p=%02x cf=%d zf=%d if=%d df=%d vf=%d nf=%d\n",
+      cpu.regs.word.pc,
+      cpu.regs.byte.a,
+      cpu.regs.byte.x,
+      cpu.regs.byte.y,
+      cpu.regs.byte.s,
+      cpu.regs.byte.p,
+      cpu.regs.bit.cf,
+      cpu.regs.bit.zf,
+      cpu.regs.bit._if,
+      cpu.regs.bit.df,
+      cpu.regs.bit.vf,
+      cpu.regs.bit.nf
+    );
+#endif
+
+    int pc = cpu.regs.word.pc;
+    cpu_6800_execute(&cpu);
+    if (pc == cpu.regs.word.pc) {
+      printf("hung at %04x\n", pc);
+      break;
+    }
+  }
+#endif
+
+  return 0;
+}

diff --git a/sim68xx b/sim68xx
new file mode 160000 (submodule)
index 0000000..27b5518
--- /dev/null
+++ b/sim68xx
@@ -0,0 +1 @@
+Subproject commit 27b551853274856ca0f7c50c5a2108d98f00d11d