Serial read support, add embedded Forp repl over serial port to game

defs.frp

@@ -69,11 +69,3 @@ key  const sp
   begin dup @ not while suspend repeat ( wait for mail )
   dup @ 0 rot ! ;
 
-
-: start-repl activate
-  stdout
-  ' log-emit task-echo !
-  begin receive loadstring again ;
-task const REPL
-
-REPL start-repl

game.frp

@@ -0,0 +1,7 @@
+: start-repl activate
+  ' seremit task-emit !
+  ' log-emit task-echo !
+  begin receive loadstring again ;
+task const REPL
+
+REPL start-repl

serial.c

@@ -1,3 +1,4 @@
+#include <stdio.h>
 #include <dos.h>
 #include "serial.h"
 
@@ -6,18 +7,72 @@ int comport = 0;
 #define SER_LATCH_LO 0
 #define SER_LATCH_HI 1
 #define SER_TX 0
+#define SER_RX 0
+#define SER_IER 1
 #define SER_LCR 3
+#define SER_MCR 4
 #define SER_LSR 5
 
+#define PIC1 0x20
+#define OCW1 0x21
+#define PIC_EOI 0x20
+
+// COM1 - IRQ4, COM2 - IRQ3, COM3 - IRQ4, COM4 - IRQ3
+#define SER_IRQ(port) (4 - (port % 2))
+#define SER_VECTOR(irq) (0x08 + (irq))
+
+static char readbuf[SER_READ_BUFFER_SIZE];
+static int ireadbufStart = 0;
+static volatile int ireadbufLim = 0;
+static int irq = 0;
+
+static void interrupt (*oldSerISR)() = NULL;
+
+static void interrupt ser_isr() {
+  while (inp(comport + SER_LSR) & 0x01) {
+    readbuf[ireadbufLim] = inp(comport + SER_RX);
+    ireadbufLim = (ireadbufLim + 1) % SER_READ_BUFFER_SIZE;
+  }
+  outp(PIC1, PIC_EOI);
+}
+
+static void ser_cleanup() {
+  if (irq) {
+    int ocw = inp(OCW1) | (1 << irq);
+    outp(OCW1, ocw);
+    setvect(SER_VECTOR(irq), oldSerISR);
+    irq = 0;
+  }
+}
+
 void ser_init(int port, int baudrate, int protocol) {
   int far *comport_addr = MK_FP(0x0040, 0x0000);
-  int lcr;
+  int lcr, ocw;
   comport = comport_addr[port];
+  irq = SER_IRQ(port);
 
   outp(comport + SER_LCR, 0x80);
   outp(comport + SER_LATCH_HI, baudrate >> 8);
   outp(comport + SER_LATCH_LO, baudrate & 0xff);
   outp(comport + SER_LCR, protocol);
+  outp(comport + SER_MCR, 0x0b);
+
+  oldSerISR = getvect(SER_VECTOR(irq));
+  setvect(SER_VECTOR(irq), ser_isr);
+  ocw = inp(OCW1) & ~(1 << irq);
+  outp(OCW1, ocw);
+  outp(comport + SER_IER, 0x01);
+
+  atexit(ser_cleanup);
+}
+
+int ser_poll() {
+  int result = SER_NODATA;
+  if (ireadbufStart != ireadbufLim) {
+    result = readbuf[ireadbufStart];
+    ireadbufStart = (ireadbufStart + 1) % SER_READ_BUFFER_SIZE;
+  }
+  return result;
 }
 
 void ser_write_byte(char byte) {

serial.h

@@ -19,6 +19,10 @@
 #define BAUD_57600  0x0002
 #define BAUD_115200 0x0001
 
+#define SER_READ_BUFFER_SIZE 0x200
+#define SER_NODATA -1
+
 void ser_init(int port, int baudrate, int protocol);
+int ser_poll();
 void ser_write_byte(char byte);
 void ser_write(char *str);

testbed.c

@@ -148,17 +148,83 @@ void overworldThink() {
   scroll(game.player.x - 152, game.player.y - 92);
 }
 
-int main() {
+int main3() {
   f_init();
   f_repl();
+  return 0;
 }
-int main2() {
+
+void f_seremit() {
+  ser_write_byte(TOP().i);
+  if (TOP().i == '\n') {
+    ser_write_byte('\r');
+  }
+  DROP(1);
+}
+
+void f_keyWasPressed() {
+  TOP().i = keyWasPressed(TOP().i);
+}
+void f_keyIsDown() {
+  TOP().i = keyIsDown(TOP().i);
+}
+void f_drawSprite() { // ( x y sprite -- )
+  drawSprite(&sprites[TOP().i * SPRITE_STRIDE], ST2().i, ST1().i);
+  DROP(3);
+}
+void f_scroll() { // ( x y -- )
+  scroll(ST1().i, TOP().i);
+}
+
+void game_f_init() {
+  f_init();
+  CDEF("seremit", f_seremit);
+  CDEF("key-pressed", f_keyWasPressed);
+  CDEF("key-down", f_keyIsDown);
+  CDEF("sprite", f_drawSprite);
+  CDEF("scroll", f_scroll);
+  CDEF("draw", drawScreen);
+
+  f_loadfile("game.frp");
+}
+
+void f_poll() {
+  static char line[256] = { 0 };
+
+  int i = strlen(line);
+  int value;
+  for (value = ser_poll(); value != SER_NODATA; value = ser_poll()) {
+    if (value == '\b' || value == 127) {
+      i --;
+    } else {
+      line[i] = value;
+      i ++;
+    }
+    line[i] = '\0';
+    ser_write_byte(value); // echo
+
+    if (value == '\r') {
+      line[i - 1] = '\n';
+      ser_write_byte('\n');
+      PUSHS(line);
+      f_runstring("REPL send");
+      f_taskloop();
+      i = 0;
+      line[i] = '\0';
+    }
+  }
+}
+
+int main() {
   game_init();
+  game_f_init();
+
   ser_init(SER_COM2, BAUD_19200, SER_8N1);
-  ser_write("JORTS QUEST DEBUG OUTPUT\r\n");
 
   while (!keyIsDown(K_ESC)) {
     kbd_debounce();
+    f_poll();
+
     if (game.state == STATE_MAP) {
       overworldThink();
     } else if (game.state == STATE_DIALOG) {