nascom.c

   1 /*   VirtualNascom, a Nascom II emulator.
   2
   3    Copyright (C) 2000  Tommy Thorn
   4    Copyright (C) 1995,1998  Frank D. Cringle.
   5
   6 NasEmu is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 2 of the License, or (at your
   9 option) any later version.
  10
  11 This program is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with this program; if not, write to the Free Software
  18 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  19
  20
  21
  22    A Nascom consists of:
  23
  24     - a Z80 CPU,
  25     - an UART,
  26     - a bitmapped keyboard,
  27     - memory:
  28         0000 - 07ff  2 KB ROM monitor,
  29         0800 - 0bff  1 KB screen memory,
  30         0c00 - 0fff  1 KB workspace
  31         1000 - dfff       memory
  32         e000 - ffff  8 KB of MS Basic
  33
  34   With the Z80 emulator in place the first thing to get working is the
  35   screen memory.  The "correct" way to simulate screen memory is to
  36   trap upon writes, but that would be slow.  We do it any just to get
  37   started.
  38
  39
  40   */
  41
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44 #include <getopt.h>
  45 #include <ctype.h>
  46 #include "simz80.h"
  47 #include "nascom.h"
  48
  49
  50 unsigned char keym[9] = {
  51     0,  /* ? ? ? Shift ? ? ? ? */
  52     0,  /* ?!TXF5BH  ! = Up*/
  53     0,  /* ?!YZD6NJ  ! = Left*/
  54     0,  /* ?!USE7MK  ! = Down */
  55     0,  /* ?!IAW8,L  ! = Right */
  56     0,  /* ??OQ39.; */
  57     0,  /* ?[P120/: */
  58     0,  /* ?]R C4VG */
  59     0   /* ? ? CR - Newline BS */
  60 };
  61
  62 unsigned char keyp = 0;
  63 unsigned char port0;
  64
  65 static void
  66 usage(void)
  67 {
  68     fprintf(stderr,
  69             "Usage: %s {flags} {commands}\n"
  70             "           -m <file>       use <file> as monitor (default is nasysy3.nal)\n"
  71             "           -v              verbose\n"
  72             ,progname);
  73     exit (1);
  74 }
  75
  76 void load_nascom(const char *file)
  77 {
  78     FILE *f = fopen(file, "r");
  79     int a, b1, b2, b3, b4, b5, b6, b7, b8;
  80     int count = 0;
  81     int ch;
  82
  83     if (!f) {
  84         perror(file);
  85         exit(1);
  86     }
  87
  88     if (vflag)
  89         printf("Loading %s", file);
  90
  91     for (; !feof(f) ;) {
  92         if (fscanf(f, "%x %x %x %x %x %x %x %x %x",
  93                    &a, &b1, &b2, &b3, &b4, &b5, &b6, &b7, &b8) == 9) {
  94             RAM(a)   = b1;
  95             RAM(a+1) = b2;
  96             RAM(a+2) = b3;
  97             RAM(a+3) = b4;
  98             RAM(a+4) = b5;
  99             RAM(a+5) = b6;
 100             RAM(a+6) = b7;
 101             RAM(a+7) = b8;
 102             count += 8;
 103         }
 104
 105         do
 106             ch = fgetc(f);
 107         while (ch != -1 && ch != '\n');
 108
 109         if (ch == -1)
 110             break;
 111     }
 112
 113     fclose(f);
 114     if (vflag)
 115         printf(". Successfully loaded %d bytes\n", count);
 116 }
 117
 118 int main(int argc, char **argv)
 119 {
 120     int c;
 121
 122     setup(argc, argv);
 123
 124     monitor = "nassys3.nal";
 125     progname = argv[0];
 126
 127
 128 #ifdef MMU
 129     for (c=0; c<MEMSIZE/4; ++c) pagetable[c]=ram+(c<<12);
 130 #endif
 131
 132     while ((c = getopt(argc, argv, "m:v")) != EOF)
 133         switch (c) {
 134         case 'm':
 135             monitor = optarg;
 136             break;
 137         case 'v':
 138             vflag = 1;
 139             break;
 140         case '?':
 141             usage();
 142         }
 143
 144     if (vflag)
 145         puts("VirtualNascom, a Nascom 2 emulator version " VERSION "\n"
 146              "Copyright 2000 Tommy Thorn.  Based on\n"
 147              "Yet Another Z80 Emulator version " YAZEVERSION
 148              ", Copyright 1995,1998 Frank D. Cringle.\n"
 149              "NasEmu comes with ABSOLUTELY NO WARRANTY; for details\n"
 150              "see the file \"COPYING\" in the distribution directory.\n");
 151
 152     load_nascom(monitor);
 153     load_nascom("basic.nal");
 154
 155     for ( ; optind < argc; optind++)
 156         load_nascom(argv[optind]);
 157
 158     simz80(pc, 20, NULL /*xhandleevent*/);
 159
 160     fprintf(stderr,"HALT\n\r");
 161     fprintf(stderr,"PC   SP   IR   IX   IY   AF   BC   DE   HL   AF'  BC'  DE'  HL'\n\r");
 162     fprintf(stderr,"%04x %04x %04x %04x %04x %04x %04x %04x %04x %04x %04x %04x %04x\n\r",pc,sp,ir,ix,iy,af[af_sel],regs[regs_sel].bc,regs[regs_sel].de,regs[regs_sel].hl,af[1-af_sel],regs[1-regs_sel].bc,regs[1-regs_sel].de,regs[1-regs_sel].hl);
 163     exit(0);
 164 }
 165
 166 void out(unsigned int port, unsigned char value)
 167 {
 168     unsigned int down_trans;
 169
 170     if (0) fprintf(stdout, "[%02x] <- %02x\n", port, value);
 171
 172     switch (port) {
 173     case 0:
 174         /* KBD */
 175         down_trans = port0 & ~value;
 176         port0 = value;
 177
 178         if ((1 & down_trans) && keyp < 9) keyp++;
 179         if (2 & down_trans) keyp = 0;
 180         break;
 181
 182     default: ;
 183     }
 184 }
 185
 186 int in(unsigned int port)
 187 {
 188     if (0) fprintf(stdout, "<- [%02x]\n", port);
 189
 190     switch (port) {
 191     case 0:
 192         /* KBD */
 193         /* printf("[%d]", keyp); */
 194         return ~keym[keyp];
 195     case 2:
 196         /* Status port on the UART */
 197         return 0;
 198     default:
 199         return 0;
 200     }
 201 }
 202
 203 #if 0
 204
 205 #include "xvirtualnascom.h"
 206 #include <X11/Intrinsic.h>
 207 #include <X11/StringDefs.h>
 208 #include <X11/Xos.h>
 209 #include <X11/cursorfont.h>
 210 #include <X11/Xutil.h>
 211 #include <X11/xpm.h>
 212
 213 #define XK_MISCELLANY 1
 214 #include <X11/keysymdef.h>
 215
 216 void slow_write(unsigned int a, unsigned char v)
 217 {
 218     if (INSCREEN(a)) {
 219         unsigned int y = (a-0x800) / 64;
 220         unsigned int x = (a-0x800) % 64;
 221         /* fprintf(stdout, "putbyte %04x %02x '%c'\n", a, v, v); */
 222         if (10 <= x && x < 58 && ' ' <= v) {
 223             if (y == 15)
 224                 y = 0;
 225             else
 226                 ++y;
 227
 228             xputch(x-10, y, v);
 229         }
 230     }
 231     if (0x800 <= a && a <= 0xE000)
 232         RAM(a) = v;
 233 }
 234
 235 static char * kbd_translation[] = {
 236 /* 0 */  "xxxxxxxx",
 237 /* 1 */  "xyTXF5BH",
 238 /* 2 */  "xyYZD6NJ",
 239 /* 3 */  "xyUSE7MK",
 240 /* 4 */  "xyIAW8,L",
 241 /* 5 */  "xxOQ39.;",
 242 /* 6 */  "x[P120/'",
 243 /* 7 */  "x]R C4VG",
 244 /* 8 */  "x\rxxx-\n\007"
 245 };
 246
 247 void EventHandler(Widget w, caddr_t data, XEvent *ev)
 248 {
 249     KeySym keysym;
 250     int i = -1, bit = 0;
 251
 252     if (ev->xany.type != KeyPress && ev->xany.type != KeyRelease)
 253         return;
 254
 255     keysym = XKeycodeToKeysym(dpy, ev->xkey.keycode, 0);
 256
 257     if ((unsigned long) keysym < 128) {
 258         int ch = toupper(keysym);
 259         for (i = 0; i < 9; ++i)
 260             for (bit = 0; bit < 8; ++bit)
 261                 if (kbd_translation[i][7-bit] == ch)
 262                     goto found;
 263         i = -1;
 264         found:;
 265     } else
 266         switch (keysym) {
 267         case XK_Shift_L:
 268         case XK_Shift_R:   i = 0, bit = 4; break;
 269         case XK_Up:        i = 1, bit = 6; break;
 270         case XK_Left:      i = 2, bit = 6; break;
 271         case XK_Down:      i = 3, bit = 6; break;
 272         case XK_Right:     i = 4, bit = 6; break;
 273         case XK_BackSpace: i = 8, bit = 0; break;
 274         case XK_Return:    i = 8, bit = 1; break;
 275         case XK_End: {
 276             /* Undocumented hack */
 277             FILE *f;
 278             f = fopen("screendump", "w");
 279             fwrite((const void *) (ram+0x800), 1, 1024, f);
 280             fclose(f);
 281             if (vflag) printf("Screen dumped\n");
 282             break;
 283         }}
 284
 285     if (i != -1) {
 286         if (ev->xany.type == KeyPress)
 287             keym[i] |= 1 << bit;
 288         else
 289             keym[i] &= ~(1 << bit);
 290     }
 291 }
 292
 293 #endif