Add support for Trevor Flowers' mini VT100.

vt100/Makefile

@@ -10,7 +10,7 @@ endif
 check: vt100 ../test/test.sh
 	cd ..; sh test/test.sh
 WARN=-Wall -Wno-unused-parameter -Wno-parentheses -Wno-unused-result
-SRC=main.c cpu.c sys.c ddt.c pusart.c \
+SRC=main.c cpu.c sys.c ddt.c pusart.c flowers.c \
 	nvr.c keyboard.c video.c rom.c sound.c render.c \
 	../common/sdl.c ../common/opengl.c ../common/event.c \
 	../common/logger.c ../common/pty.c

vt100/flowers.c

@@ -0,0 +1,66 @@
+#include <fcntl.h>
+#include <errno.h>
+#include <unistd.h>
+#include <string.h>
+#include <termios.h>
+#include <sys/ioctl.h>
+#include "vt100.h"
+
+int flowers = -1; // Trevor Flowers' mini VT100.
+
+void flowers_init(const char *device)
+{
+  struct termios t;
+
+  flowers = open(device, O_RDWR);
+  if (flowers == -1)
+    panic("Couldn't open %s: %s", optarg, strerror (errno));
+
+  memset(&t, 0, sizeof t);
+  tcsetattr(flowers, TCSAFLUSH, &t);
+}
+
+void flowers_leds(u8 data)
+{
+  char command[100];
+  int n;
+  if (flowers < 0)
+    return;
+  n = snprintf(command, sizeof command, "\nSET_ALL_LEDS %c%c%c%c%c%c%c\n",
+               (data & 0x20) ? '0' : '1',
+               (data & 0x20) ? '1' : '0',
+               (data & 0x10) ? '1' : '0',
+               (data & 0x08) ? '1' : '0',
+               (data & 0x04) ? '1' : '0',
+               (data & 0x02) ? '1' : '0',
+               (data & 0x01) ? '1' : '0');
+  write(flowers, command, n);
+}
+
+static const char *const prefix = "SPECIAL_KEY: ";
+static const char *pointer = prefix;
+
+int flowers_key(void)
+{
+  char data;
+  int n;
+
+  if (ioctl(flowers, FIONREAD, &n) != 0)
+    return -1;
+  if (n < 1)
+    return -1;
+  if (read(flowers, &data, 1) != 1)
+    return -1;
+
+  if (*pointer == 0) {
+    pointer = prefix;
+    return data;
+  }
+
+  if (data != *pointer)
+    pointer = prefix;
+  if (data == *pointer)
+    pointer++;
+
+  return -1;
+}

vt100/keyboard.c

@@ -10,6 +10,8 @@ static SDL_SpinLock kbd_lock;
 
 static void scanning (void);
 static EVENT (scan_event, scanning);
+static void check_flowers (void);
+static EVENT (flowers_event, check_flowers);
 
 uint8_t keymap (SDL_Scancode key)
 {
@@ -122,6 +124,8 @@ static void keyboard_out (u8 port, u8 data)
   u8 changed = previous ^ data;
   if ((vt100_flags & 0x80) == 0)
     return;
+  if (changed & 0x3F)
+    flowers_leds(data);
   if (changed & ~0x40)
     LOG (KEY, "LED:%c%c%c%c %s %s%s",
             (data & 0x08) ? '1' : '-',
@@ -180,11 +184,30 @@ static void scanning (void)
   SDL_AtomicUnlock (&kbd_lock);
 }
 
+static void check_flowers (void)
+{
+  int key = flowers_key ();
+  add_event (1000, &flowers_event);
+  SDL_AtomicLock (&kbd_lock);
+  switch (key) {
+  case '2': // SETUP
+    down[0x7B] ^= 1;
+    break;
+  case '3': // BREAK
+    down[0x23] ^= 1;
+    break;
+  }
+  SDL_AtomicUnlock (&kbd_lock);
+}
+
 void reset_keyboard (void)
 {
   register_port (0x82, keyboard_in, keyboard_out);
   vt100_flags |= 0x80;
   memset (down, 0, sizeof down);
   down[0x7F] = 1;
   scan = 0x80;
+  flowers_leds(0);
+  if (flowers > 0)
+    add_event (1000, &flowers_event);
 }

vt100/main.c

@@ -136,6 +136,7 @@ void help(void)
     "  -B      Treat backspace as rubout (currently not implemented).\n"
     "  -R PROG Run CP/M binary file [path/to/]PROG.\n"
     "  -D      Debug mode.\n"
+    "  -F DEV  Open DEV to talk to Trevor Flowers' mini VT100\n"
     "\n"
     "Project page: https://github.com/larsbrinkhoff/terminal-simulator\n"
     , argv0);
@@ -157,7 +158,7 @@ int main (int argc, char **argv)
   sdl_capslock (0x7E); //Default is capslock.
 
   argv0 = argv[0];
-  while ((opt = getopt (argc, argv, "aghB2fR:DCQN:c:")) != -1) {
+  while ((opt = getopt (argc, argv, "aghB2fF:R:DCQN:c:")) != -1) {
     switch (opt) {
     case 'g':
       pixcolor = 1;
@@ -195,6 +196,9 @@ int main (int argc, char **argv)
     case 'c':
       curvature = atof (optarg);
       break;
+    case 'F':
+      flowers_init(optarg);
+      break;
     default:
       usage();
       break;

vt100/vt100.h

@@ -14,6 +14,8 @@ typedef uint8_t u8;
 #define RST6 0xF7
 #define RST7 0xFF
 
+extern void panic (char *fmt, ...);
+
 extern u8 memory[0x10000];
 extern u16 starta;
 extern unsigned long long get_cycles (void);
@@ -62,3 +64,8 @@ extern void reset_sound (void);
 extern void nvr_clock (void);
 extern void key_down (u8 code);
 extern void key_up (u8 code);
+
+extern int flowers;
+extern void flowers_init(const char *device);
+extern void flowers_leds(u8 data);
+extern int flowers_key(void);