Implement game pad and timer

core/vb.c

@@ -90,6 +90,39 @@ struct VB {
         int      step;      /* Operation sub-task ID */
     } cpu;
 
+    /* Game pad */
+    struct {
+
+        /* Hardware state */
+        uint8_t  k_int_inh; /* Interrupt acknowledge/disable */
+        uint8_t  para_si;   /* Read reset signal */
+        uint8_t  s_abt_dis; /* Abort hardware read */
+        uint8_t  sdhr;      /* High key bits */
+        uint8_t  sdlr;      /* Low key bits */
+        uint32_t si_stat;   /* Hardware read in progress */
+        uint8_t  soft_ck;   /* Controller communication signal */
+
+        /* Simulation state */
+        uint8_t keys; /* Next input bits */
+        int     step; /* Software read processing phase */
+    } pad;
+
+    /* Timer */
+    struct {
+
+        /* Hardware state */
+        uint8_t t_clk_sel; /* Counter tick duration */
+        uint8_t t_enb;     /* Enable timer */
+        uint8_t tim_z_int; /* Enable interrupt */
+        uint8_t z_stat;    /* Zero status */
+
+        /* Simulation state */
+        uint32_t clocks;  /* Master clocks to wait */
+        uint16_t counter; /* Current counter value */
+        uint16_t reload;  /* Reload counter value */
+        uint32_t until;   /* Clocks until interrupt condition */
+    } tmr;
+
     /* VIP */
     struct {
 
@@ -168,6 +201,7 @@ struct VB {
     } vip;
 
     /* Other state */
+    uint8_t wcr;           /* Wait controller state */
     uint8_t wram[0x10000]; /* System RAM */
 
     /* Application data */
@@ -199,6 +233,8 @@ static int32_t SignExtend(int32_t value, int32_t bits) {
 
 /******************************** Sub-Modules ********************************/
 
+#include "game-pad.c"
+#include "timer.c"
 #include "bus.c"
 #include "cpu.c"
 #include "vip.c"
@@ -211,7 +247,9 @@ static int32_t SignExtend(int32_t value, int32_t bits) {
 static int sysEmulate(VB *sim, uint32_t clocks) {
     return
         cpuEmulate(sim, clocks) |
-        vipEmulate(sim, clocks)
+        vipEmulate(sim, clocks) |
+        padEmulate(sim, clocks) |
+        tmrEmulate(sim, clocks)
     ;
 }
 
@@ -219,6 +257,8 @@ static int sysEmulate(VB *sim, uint32_t clocks) {
 static uint32_t sysUntil(VB *sim, uint32_t clocks) {
     clocks = cpuUntil(sim, clocks);
     clocks = vipUntil(sim, clocks);
+    clocks = padUntil(sim, clocks);
+    clocks = tmrUntil(sim, clocks);
     return clocks;
 }
 
@@ -295,6 +335,11 @@ VBAPI vbOnFrame vbGetFrameCallback(VB *sim) {
     return sim->onFrame;
 }
 
+/* Retrieve the current game pad key state */
+VBAPI uint16_t vbGetKeys(VB *sim) {
+    return sim->pad.keys;
+}
+
 /* Retrieve the most recent frame image pixels */
 VBAPI void vbGetPixels(VB *sim, void *left, int leftStrideX, int leftStrideY,
     void *right, int rightStrideX, int rightStrideY) {
@@ -391,6 +436,9 @@ VBAPI int32_t vbRead(VB *sim, uint32_t address, int type) {
 VBAPI VB* vbReset(VB *sim) {
     int x; /* Iterator */
 
+    /* Wait controller */
+    sim->wcr = 0x00;
+
     /* WRAM (the hardware does not do this) */
     for (x = 0; x < 0x10000; x++)
         sim->wram[x] = 0x00;
@@ -398,6 +446,8 @@ VBAPI VB* vbReset(VB *sim) {
     /* Components */
     cpuReset(sim);
     vipReset(sim);
+    padReset(sim);
+    tmrReset(sim);
     return sim;
 }
 
@@ -451,6 +501,11 @@ VBAPI vbOnFrame vbSetFrameCallback(VB *sim, vbOnFrame callback) {
     return prev;
 }
 
+/* Specify new game pad keys */
+VBAPI uint16_t vbSetKeys(VB *sim, uint16_t keys) {
+    return sim->pad.keys = keys;
+}
+
 /* Specify a new value for the program counter */
 VBAPI uint32_t vbSetProgramCounter(VB *sim, uint32_t value) {
     sim->cpu.operation = CPU_FETCH;