Changeset ebc8f69 in buchla-emu

Timestamp:

07/20/2017 08:18:39 PM (7 years ago)

Author:

Thomas Lopatic <thomas@…>

Branches:

master

Children:

4c71d39

Parents:

2147e53

Message:

Throttle CPU to 7 MHz.

Location:

emu

Files:

• all.h (modified) (1 diff)
• cpu.c (modified) (3 diffs)
• sdl.c (modified) (1 diff)

emu/all.h

@@ -21 +21 @@
 #include <stdio.h>
 #include <unistd.h>
+
+#include <xmmintrin.h>
 
 #include <m68k.h>

emu/cpu.c

@@ -26 +26 @@
 bool cpu_verbose = false;
 
-#define CYCLES 70
+#define CPU_FREQ 7000000
+#define PER_SEC 100000
 
 #define APP_START 0x10000
@@ -450 +451 @@
         m68k_pulse_reset();
 
+        uint64_t freq = SDL_GetPerformanceFrequency();
+        uint64_t quan = freq / PER_SEC;
+        inf("freq %" PRIu64 " quan %" PRIu64, freq, quan);
+
         bool run = true;
 
         while (run) {
-                m68k_execute(CYCLES);
+                uint64_t until = SDL_GetPerformanceCounter() + quan;
+
+                m68k_execute(CPU_FREQ / PER_SEC);
                 hw_exec();
 
@@ -461 +468 @@
                         if (ev.type == SDL_QUIT) {
                                 run = false;
-                                break;
                         }
                 }
+
+                while (SDL_GetPerformanceCounter() < until) {
+                        _mm_pause();
+                }
         }
 

emu/sdl.c

@@ -28 +28 @@
 void sdl_init(void)
 {
-        if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_EVENTS) < 0) {
+        if (SDL_Init(SDL_INIT_VIDEO | SDL_INIT_EVENTS | SDL_INIT_TIMER) < 0) {
                 fprintf(stderr, "SDL_Init() failed: %s\n", SDL_GetError());
                 exit(1);