HALT fix, QoL tweaks

app/App.js

@@ -121,7 +121,7 @@ globalThis.App = class App {
     // ROM buffer has been configured
     setROM(msg) {
         let dbg = this.debuggers[msg.sim];
-        dbg.refresh();
+        dbg.refresh(true);
     }
 
 

app/Debugger.js

@@ -46,8 +46,8 @@ globalThis.Debugger = class Debugger {
     }
 
     // Reload all output
-    refresh() {
+    refresh(seekToPC) {
-        this.cpu   .refresh();
+        this.cpu   .refresh(seekToPC);
         this.memory.refresh();
     }
 

app/windows/CPUWindow.js

@@ -234,7 +234,7 @@
             case "ReadBuffer"  : this.readBuffer  (msg); break;
             case "SetRegister" : this.setRegister (msg); break;
             case "RunNext": case "SingleStep":
-                this.refresh(true); break;
+                this.debug.refresh(true); break;
         }
     }
 

app/windows/Disassembler.js

@@ -345,7 +345,9 @@
         let reg2 = this.PROREGNAMES[bits >> 21 & 31];
         let reg1 = this.PROREGNAMES[bits >> 16 & 31];
         let disp = this.signExtend(bits & 0xFFFF, 16);
-        disp = disp == 0 ? "" : (disp < 0 ? "-" : "") + "0x" +
+        disp = disp == 0 ? "" : (disp < -255 || disp > 255) ? "0x" +
+            ("000" + (disp & 0xFFFF).toString(16).toUpperCase()).slice(-4) :
+            (disp < 0 ? "-" : "") + "0x" +
                 Math.abs(disp).toString(16).toUpperCase();
         switch (inst.opcode) {
             case 0b110000: // LD.B

app/windows/MemoryWindow.js

@@ -99,8 +99,8 @@ globalThis.MemoryWindow = class MemoryWindow extends Toolkit.Window {
     // Message received
     message(msg) {
         switch (msg.command) {
-            case "ReadBuffer": this.readBuffer(msg); break;
+            case "ReadBuffer": this.readBuffer(msg)     ; break;
-            case "Write"     : this.debug.refresh(); break;
+            case "Write"     : this.debug.refresh(false); break;
         }
     }
 
@@ -380,6 +380,7 @@ MemoryWindow.Row = class Row extends Toolkit.Panel {
 
         // Configure element
         this.element.setAttribute("role", "row");
+        this.element.addEventListener("pointerdown", e=>this.onpointerdown(e));
 
         // Address label
         this.addr = this.add(parent.newLabel({ text: "\u00a0" }));
@@ -418,6 +419,31 @@ MemoryWindow.Row = class Row extends Toolkit.Panel {
         return (this.wnd.address + this.offset & 0xFFFFFFFF) >>> 0;
     }
 
+    // Pointer down event handler
+    onpointerdown(e) {
+
+        // Error checking
+        if (e.button != 0)
+            return;
+
+        // Check whether the click is within the columns of cells
+        let next = this.cells[0].getBounds();
+        if (e.x < next.left)
+            return;
+
+        // Compute which cell was clicked
+        for (let x = 0; x < 16; x++) {
+            let cur = next;
+            if (x < 15) {
+                next = this.cells[x + 1].getBounds();
+                if (e.x < (cur.right + next.left) / 2)
+                    return this.wnd.setSelected(this.cells[x].address());
+            } else if (e.x < cur.right)
+                return this.wnd.setSelected(this.cells[x].address());
+        }
+
+    }
+
 };
 
 // One cell of output
@@ -435,7 +461,6 @@ MemoryWindow.Cell = class Cell extends Toolkit.Label {
         // Configure element
         this.element.setAttribute("role", "gridcell");
         this.element.setAttribute("name", "byte");
-        this.element.addEventListener("pointerdown", e=>this.onpointerdown(e));
 
         parent.add(this);
     }
@@ -473,10 +498,4 @@ MemoryWindow.Cell = class Cell extends Toolkit.Label {
         return (this.wnd.address + this.offset & 0xFFFFFFFF) >>> 0;
     }
 
-    // Pointer down event handler
-    onpointerdown(e) {
-        if (e.button == 0)
-            this.wnd.setSelected(this.address());
-    }
-
 };

core/cpu.c

@@ -979,7 +979,7 @@ static void cpuDIVU(VB *emu, VB_INSTRUCTION *inst) {
 static void cpuHALT(VB *emu, VB_INSTRUCTION *inst) {
     emu->cpu.state = CPU_HALTED;
     inst->size     = 0;
-    /* TODO: Find out how many clocks this takes */
+    /* emu->cpu.clocks = ? */
 }
 
 /* Input Byte */
@@ -1491,8 +1491,8 @@ static int cpuExecute(VB *emu) {
     /* Post-instruction tasks */
     if (emu->cpu.causeCode == 0 && !emu->cpu.busWait) {
 
-        /* Advance to next instruction if not processing a bit string */
+        /* Advance to next instruction */
-        if (!emu->cpu.substring)
+        if (emu->cpu.state != CPU_HALTED && !emu->cpu.substring)
             emu->cpu.pc += inst->size;
 
         /* Check for interrupts */
@@ -1505,11 +1505,10 @@ static int cpuExecute(VB *emu) {
         emu->cpu.substring = 0;
     }
 
-    /* Switch to fetch mode if not halting and execution has completed */
+    /* Switch to fetch mode */
     else if (emu->cpu.state != CPU_HALTED &&
         !emu->cpu.busWait && !emu->cpu.substring) {
         emu->cpu.state = CPU_FETCH;
-        emu->cpu.fetch = 0;
     }
 
     return 0;
@@ -1518,6 +1517,7 @@ static int cpuExecute(VB *emu) {
 /* Enter an exception state */
 static int cpuException(VB *emu) {
     uint16_t causeCode = emu->cpu.causeCode;
+    int      irq       = causeCode < 0xFF00;
 
     /* Fatal exception */
     if (emu->cpu.psw.np) {
@@ -1587,7 +1587,7 @@ static int cpuException(VB *emu) {
     else {
         emu->cpu.ecr.eicc = causeCode;
         emu->cpu.eipsw    = vbGetSystemRegister(emu, VB_PSW);
-        emu->cpu.eipc     = emu->cpu.pc;
+        emu->cpu.eipc     = emu->cpu.pc + (irq ? 2 : 0);
         emu->cpu.eipcFrom = emu->cpu.pcFrom;
         emu->cpu.eipcTo   = emu->cpu.pcTo;
         emu->cpu.psw.ep   = 1;
@@ -1596,7 +1596,7 @@ static int cpuException(VB *emu) {
     }
 
     /* Interrupt */
-    if (causeCode < 0xFF00)
+    if (irq)
         emu->cpu.psw.i += emu->cpu.psw.i == 15 ? 0 : 1;
 
     /* Update state */
@@ -1690,10 +1690,11 @@ static int cpuEmulate(VB *emu, uint32_t clocks) {
 
         /* Processing by operations state */
         switch (emu->cpu.state) {
-            case CPU_FETCH    : if (cpuFetch    (emu)) return 1; break;
+            case CPU_EXCEPTION: if ( cpuException(emu)) return 1; break;
-            case CPU_EXECUTE  : if (cpuExecute  (emu)) return 1; break;
+            case CPU_EXECUTE  : if ( cpuExecute  (emu)) return 1; break;
-            case CPU_EXCEPTION: if (cpuException(emu)) return 1; break;
+            case CPU_FATAL    :                         return 0; break;
-            case CPU_HALTED   : if (cpuCheckIRQs(emu)) return 0; break;
+            case CPU_FETCH    : if ( cpuFetch    (emu)) return 1; break;
+            case CPU_HALTED   : if (!cpuCheckIRQs(emu)) return 0; break;
         }
 
     } while (clocks > 0);
@@ -1702,6 +1703,45 @@ static int cpuEmulate(VB *emu, uint32_t clocks) {
     return 0;
 }
 
+/* Simulate a hardware reset */
+static void cpuReset(VB *emu) {
+    int x; /* Iterator */
+
+    /* Registers */
+    vbSetProgramCounter(emu,         0xFFFFFFF0);
+    vbSetSystemRegister(emu, VB_ECR, 0x0000FFF0);
+    vbSetSystemRegister(emu, VB_PSW, 0x00008000);
+
+    /* Cache */
+    vbSetSystemRegister(emu, VB_CHCW, 0x00000000);
+
+    /* Other state */
+    emu->cpu.busWait   = 0;
+    emu->cpu.state     = CPU_FETCH;
+    emu->cpu.substring = 0;
+    for (x = 0; x < 5; x++)
+        emu->cpu.irq[x] = 0;
+
+    /* Other registers (the hardware does not do this) */
+    for (x = 0; x < 32; x++)
+        emu->cpu.program[x] = 0x00000000;
+    emu->cpu.adtre    = 0x00000000;
+    emu->cpu.eipc     = 0x00000000;
+    emu->cpu.eipsw    = 0x00000000;
+    emu->cpu.fepc     = 0x00000000;
+    emu->cpu.fepsw    = 0x00000000;
+    emu->cpu.sr29     = 0x00000000;
+    emu->cpu.sr31     = 0x00000000;
+
+    /* History tracking */
+    emu->cpu.eipcFrom = 0xFFFFFFF0;
+    emu->cpu.eipcTo   = 0xFFFFFFF0;
+    emu->cpu.fepcFrom = 0xFFFFFFF0;
+    emu->cpu.fepcTo   = 0xFFFFFFF0;
+    emu->cpu.pcFrom   = 0xFFFFFFF0;
+    emu->cpu.pcTo     = 0xFFFFFFF0;
+}
+
 /* Determine the number of clocks before a break condititon could occur */
 static uint32_t cpuUntil(VB *emu, uint32_t clocks) {
 

core/vb.c

@@ -197,36 +197,8 @@ int32_t vbRead(VB *emu, uint32_t address, int type, int debug) {
 void vbReset(VB *emu) {
     uint32_t x; /* Iterator */
 
-    /* CPU registers */
+    /* Subsystem components */
-    vbSetProgramCounter(emu,         0xFFFFFFF0);
+    cpuReset(emu);
-    vbSetSystemRegister(emu, VB_ECR, 0x0000FFF0);
-    vbSetSystemRegister(emu, VB_PSW, 0x00008000);
-
-    /* Extra CPU registers (the hardware does not do this) */
-    for (x = 0; x < 32; x++)
-        emu->cpu.program[x] = 0x00000000;
-    emu->cpu.adtre  = 0x00000000;
-    emu->cpu.eipc   = 0x00000000;
-    emu->cpu.eipsw  = 0x00000000;
-    emu->cpu.fepc   = 0x00000000;
-    emu->cpu.fepsw  = 0x00000000;
-    emu->cpu.sr29   = 0x00000000;
-    emu->cpu.sr31   = 0x00000000;
-
-    /* History tracking */
-    emu->cpu.eipcFrom = 0xFFFFFFF0;
-    emu->cpu.eipcTo   = 0xFFFFFFF0;
-    emu->cpu.fepcFrom = 0xFFFFFFF0;
-    emu->cpu.fepcTo   = 0xFFFFFFF0;
-    emu->cpu.pcFrom   = 0xFFFFFFF0;
-    emu->cpu.pcTo     = 0xFFFFFFF0;
-
-    /* Other CPU state */
-    emu->cpu.busWait   = 0;
-    emu->cpu.state     = CPU_FETCH;
-    emu->cpu.substring = 0;
-    for (x = 0; x < 5; x++)
-        emu->cpu.irq[x] = 0;
 
     /* WRAM (the hardware does not do this) */
     for (x = 0; x < 0x10000; x++)