+ + + + +
+ +LEDs: +
+ D7 D6 D5 D4 D3 D2 D1 D0
+ ○
+ ○
+ ○
+ ○
+ ○
+ ○
+ ○
+ ○
+
+ A15 A14 A13 A12 A11 A10 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0
+ ○
+ ○
+ ○
+ ○
+ ○
+ ○
+ ○
+ ○
+ ○
+ ○
+ ○
+ ○
+ ○
+ ○
+ ○
+ ○
+
CPU dump: +
+ + +Memory dump: +
+ diff --git a/js/sim8800.js b/js/sim8800.js index 4d94978..4f43d31 100644 --- a/js/sim8800.js +++ b/js/sim8800.js @@ -24,12 +24,18 @@ class Sim8800 { /** * @param {number} memSize The memory size, in bytes. * @param {number} clockRate The clock rate. + * @param {Element?} dumpCpuElem The DOM element used to render + * dumped CPU status. null to disable the feature. + * @param {Element?} dumpMemElem The DOM element used to render + * dumped memory contents. null to disable the feature. */ - constructor(memSize, clockRate) { - /** @type {number} */ + constructor(memSize, clockRate, + dumpCpuElem, dumpMemElem) { this.clockRate = clockRate; - /** @type {Array\n'];
+ for (let i = 0; i < this.mem.length; i += 16) {
+ sb.push(Sim8800.toHex(i, 4));
+ sb.push(' ');
+ for (let j = i;
+ j < Math.min(this.mem.length, i + 16);
+ j++) {
+ sb.push(Sim8800.toHex(this.mem[j], 2));
+ sb.push((j + 1) % 8 == 0 ? ' ' : ' ');
+ }
+ sb.push('\n');
+ }
+ sb.push('\n');
+ this.dumpMemElem.innerHTML = sb.join('');
+ }
+ }
+
+ /**
+ * Decodes the FLAGs register.
+ * @param {number} flags The value of the FLAGs register.
+ * @return {Object} The decoded flags.
+ */
+ decodeFlags(flags) {
+ var ret = {};
+ ret.sign = flags & 0x80 != 0;
+ ret.zero = flags & 0x40 != 0;
+ ret.auxiliaryCarry = flags & 0x10 != 0;
+ ret.parity = flags & 0x04 != 0;
+ ret.carry = flags & 0x01 != 0;
+ return ret;
+ }
+
+ /**
+ * Dumps the internal CPU status to HTML, for debugging or mornitoring.
+ */
+ dumpCpu() {
+ if (this.dumpCpuElem) {
+ var cpu = CPU8080.status();
+ var sb = ['\n'];
+ sb.push('PC = ' + Sim8800.toHex(cpu.pc, 4) + ' ');
+ sb.push('SP = ' + Sim8800.toHex(cpu.sp, 4) + '\n');
+ sb.push('A = ' + Sim8800.toHex(cpu.a, 2) + ' ');
+ sb.push('B = ' + Sim8800.toHex(cpu.b, 2) + ' ');
+ sb.push('C = ' + Sim8800.toHex(cpu.c, 2) + ' ');
+ sb.push('D = ' + Sim8800.toHex(cpu.d, 2) + '\n');
+ sb.push('E = ' + Sim8800.toHex(cpu.e, 2) + ' ');
+ sb.push('F = ' + Sim8800.toHex(cpu.f, 2) + ' ');
+ sb.push('H = ' + Sim8800.toHex(cpu.h, 2) + ' ');
+ sb.push('L = ' + Sim8800.toHex(cpu.l, 2) + '\n');
+ var flags = this.decodeFlags(cpu.f);
+ sb.push('FLAGS: ');
+ if (flags.sign) sb.push('SIGN ');
+ if (flags.zero) sb.push('ZERO ');
+ if (flags.auxiliaryCarry) sb.push('AC ');
+ if (flags.parity) sb.push('PARITY ');
+ if (flags.carry) sb.push('CARRY ');
+ sb.push('\n');
+ this.dumpCpuElem.innerHTML = sb.join('');
+ }
+ }
+
/**
* Returns the byteTo (write memory) callback.
* @return {function(number, number)}
@@ -47,8 +182,6 @@ class Sim8800 {
return function(address, value) {
address = address % self.mem.length;
self.mem[address] = value;
- window.console.log('writing byte @' + Sim8800.toHex(address, 8)
- + ' : ' + Sim8800.toHex(value, 2));
};
}
@@ -61,8 +194,6 @@ class Sim8800 {
return function(address) {
address = address % self.mem.length;
var value = self.mem[address];
- window.console.log('reading byte @' + Sim8800.toHex(address, 8)
- + ' : ' + Sim8800.toHex(value, 2));
return value;
};
}
@@ -74,8 +205,6 @@ class Sim8800 {
getWritePortCallback() {
var self = this;
return function(address, value) {
- window.console.log('writing port @' + Sim8800.toHex(address, 8)
- + ' : ' + Sim8800.toHex(value, 2));
if (address == 0xff) {
// We only care about port 0xff.
}
@@ -93,70 +222,73 @@ class Sim8800 {
if (address == 0xff) {
// We only care about port 0xff.
}
- window.console.log('reading port @' + Sim8800.toHex(address, 8)
- + ' : ' + Sim8800.toHex(value, 2));
return value;
};
}
/**
- * Formats a number to fixed length hex string.
- * @param {number} n The number to be formatted.
- * @param {number} len The output length, with leading zeros.
+ * Gets the clock ticker callback.
+ * @return {function()}
*/
- static toHex(n, len) {
- var leadingZeros = (new Array(len)).fill('0').join('');
- return (leadingZeros + n.toString(16)).substr(-len);
- }
-
- /**
- * Fills the memory with random numbers.
- */
- initMem() {
- for (let i = 0; i < this.mem.length; i++) {
- this.mem[i] = Math.floor(Math.random() * 256);
- }
- }
-
- /**
- * Dumps the memory to HTML, for debugging or monitoring.
- * @param {Element} containerElem The DOM element to hold the generated HTML.
- */
- dumpMem(containerElem) {
- var sb = ['\n'];
- for (let i = 0; i < this.mem.length; i += 16) {
- sb.push(Sim8800.toHex(i, 4));
- sb.push(' ');
- for (let j = i;
- j < Math.min(this.mem.length, i + 16);
- j++) {
- sb.push(Sim8800.toHex(this.mem[j], 2));
- sb.push((j + 1) % 8 == 0 ? ' ' : ' ');
+ getClockTickerCallback() {
+ var self = this;
+ return function(timestamp) {
+ if (self.running) {
+ var cycles = self.clockRate / 1000;
+ CPU8080.steps(cycles);
+ self.dumpCpu();
+ self.dumpMem();
+ window.setTimeout(self.getClockTickerCallback(), 1);
}
- sb.push('\n');
- }
- sb.push('\n');
- containerElem.innerHTML = sb.join('');
+ };
}
/**
- * Dumps the internal CPU status to HTML, for debugging or mornitoring.
- * @param {Element} containerElem The DOM element to hold the generated HTML.
+ * Runs a single CPU step.
*/
- dumpCpu(containerElem) {
- var cpu = CPU8080.status();
- var sb = ['\n'];
- sb.push('PC = ' + Sim8800.toHex(cpu.pc, 4) + ' ');
- sb.push('SP = ' + Sim8800.toHex(cpu.sp, 4) + '\n');
- sb.push('A = ' + Sim8800.toHex(cpu.a, 2) + ' ');
- sb.push('B = ' + Sim8800.toHex(cpu.b, 2) + ' ');
- sb.push('C = ' + Sim8800.toHex(cpu.c, 2) + ' ');
- sb.push('D = ' + Sim8800.toHex(cpu.d, 2) + '\n');
- sb.push('E = ' + Sim8800.toHex(cpu.e, 2) + ' ');
- sb.push('F = ' + Sim8800.toHex(cpu.f, 2) + ' ');
- sb.push('H = ' + Sim8800.toHex(cpu.h, 2) + ' ');
- sb.push('L = ' + Sim8800.toHex(cpu.l, 2) + '\n');
- sb.push('\n');
- containerElem.innerHTML = sb.join('');
+ singleStep() {
+ CPU8080.steps(1);
+ this.dumpCpu();
+ this.dumpMem();
+ }
+
+ /**
+ * Powers on the machine.
+ */
+ powerOn() {
+ this.stop();
+ reset();
+ this.initMem();
+ }
+
+ /**
+ * Powers off the machine.
+ */
+ powerOff() {
+ this.stop();
+ reset();
+ this.initMem();
+ }
+
+ /**
+ * Resets the machine.
+ */
+ reset() {
+ CPU8080.reset();
+ }
+
+ /**
+ * Stops the CPU.
+ */
+ stop() {
+ this.running = false;
+ }
+
+ /**
+ * Starts the CPU.
+ */
+ start() {
+ this.running = true;
+ window.setTimeout(this.getClockTickerCallback(), 1);
}
};