Fix BASIC

Fix cycle waiting
Fix warnings

src/main.c

@@ -1,18 +1,23 @@
-#include "cpu.h"
-#include "ram.h"
-#include "rom.h"
-
 #include <fcntl.h>
+#include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <termios.h>
 #include <time.h>
 #include <unistd.h>
 
-#define MACHINE_SPEED_HZ 1e6 // 1 MHz;
+#include "cpu.h"
+#include "ram.h"
+#include "rom.h"
 
-static struct termios orig_termios;
-static struct timespec sleepTime;
+#define MACHINE_SPEED_HZ 1000000ULL // 1 MHz;
+#define SYNC_CYCLES 100
+
+struct termios orig_termios;
+struct timespec emulationStart;
+
+uint64_t totalCycles = 0;
+uint64_t lastSyncCycles = 0;
 
 void restore_terminal(void) { tcsetattr(STDIN_FILENO, TCSANOW, &orig_termios); }
 
@@ -36,11 +41,13 @@ void set_nonblocking_input(void) {
 }
 
 int main(void) {
+  uint8_t *ram = NULL;
+  CPU cpu;
+
   printf("6502PC Emulator with MS Basic\n");
   printf("CTRL + G to exit\n");
 
-  uint8_t *ram = NULL;
-  CPU cpu;
+  clock_gettime(CLOCK_MONOTONIC, &emulationStart);
 
   set_nonblocking_input();
 
@@ -51,44 +58,40 @@ int main(void) {
     exit(EXIT_FAILURE);
   }
 
-  /* DEBUG */
-
-  // FILE *fp = fopen("/Users/Kili2/Documents/Projekte/6502pc/6502_65C02_functional_tests/6502_functional_test.bin", "rb");
-  // FILE *fp = fopen("/Users/Kili2/Documents/Projekte/6502pc/6502_65C02_functional_tests/6502_decimal_test.bin", "rb");
-  // FILE *fp = fopen("/mnt/c/Users/llego/source/repos/6502PC/6502_65C02_functional_tests/6502_functional_test.bin", "rb");
-  // FILE *fp = fopen("/mnt/c/Users/llego/source/repos/6502PC/6502_65C02_functional_tests/6502_decimal_test.bin", "rb");
-  /*
-  if (!fp) {
-    perror("fopen");
-    exit(EXIT_FAILURE);
-  }
-
-  fread(ram, 1, RAM_SIZE, fp);
-  if (ferror(fp)) {
-    perror("fread");
-    fclose(fp);
-    exit(EXIT_FAILURE);
-  }
-
-  fclose(fp);
-  */
-
-  /* DEBUG END*/
-
   initCPU(&cpu);
   resetCPU(&cpu, rom);
 
   while (1) {
-    uint8_t sleep = runCycle(&cpu, ram, rom);
-    if (sleep == 1) {
+    uint8_t cycles = runCycle(&cpu, ram, rom);
+    totalCycles += cycles;
+
+    // No 1 cycle instruction exists
+    if (cycles == 1) {
       printf("Illegal opcode $%02X at $%04X "
              "A=$%02X X=$%02X Y=$%02X SP=$%02X\n",
              ram[cpu.ProgrammeCounter - 1], cpu.ProgrammeCounter - 1, cpu.Accumulator, cpu.X, cpu.Y, cpu.StackPointer);
       exit(EXIT_FAILURE);
     }
-    sleepTime.tv_sec = 0;
-    sleepTime.tv_nsec = sleep * (1000 / MACHINE_SPEED_HZ);
-    nanosleep(&sleepTime, NULL);
+
+    // Sleep if batch is full
+    if (totalCycles - lastSyncCycles >= SYNC_CYCLES) {
+      struct timespec now;
+      clock_gettime(CLOCK_MONOTONIC, &now);
+
+      uint64_t elapsed_ns =
+          (uint64_t)(now.tv_sec - emulationStart.tv_sec) * 1000000000ULL + (uint64_t)(now.tv_nsec - emulationStart.tv_nsec);
+      uint64_t target_ns = totalCycles * 1000000000ULL / MACHINE_SPEED_HZ;
+
+      if (target_ns > elapsed_ns) {
+        uint64_t wait_ns = target_ns - elapsed_ns;
+
+        struct timespec wait = {.tv_sec = wait_ns / 1000000000ULL, .tv_nsec = wait_ns % 1000000000ULL};
+
+        nanosleep(&wait, NULL);
+      }
+
+      lastSyncCycles = totalCycles;
+    }
   }
 
   destroyRAM(ram);