Implement game pad and timer

core/cpu.c

@@ -1825,8 +1825,18 @@ static void cpuReset(VB *sim) {
 
 /* Determine how many clocks are guaranteed to process */
 static uint32_t cpuUntil(VB *sim, uint32_t clocks) {
-    return sim->cpu.halt || sim->cpu.clocks > clocks ?
-        clocks : sim->cpu.clocks;
+
+    /* Halting */
+    if (sim->cpu.halt) {
+        return
+            sim->cpu.operation == CPU_HALTING                      &&
+            !(sim->cpu.psw.id | sim->cpu.psw.ep | sim->cpu.psw.np) &&
+            IRQ_LEVELS[sim->cpu.irq] < sim->cpu.psw.i
+        ? 0 : clocks;
+    }
+
+    /* Not halting */
+    return sim->cpu.clocks > clocks ? clocks : sim->cpu.clocks;
 }
 
 #endif /* VBAPI */