helper_functions.js

var loadCounter = 0;

function loadProperty(propname, defval, convtobool){
	var prop = window.localStorage.getItem(propname);

	if (prop == null) {
		prop = defval;
		window.localStorage.setItem(propname, prop);
		return prop;
	}

	if (convtobool){
		prop = (prop == "true");
	}

	return prop;
}

function RAMbou() {
	if (RAM.length > 32768) {  // 32KB max size
		RAM = RAM.subarray(0, 32768);
		console.log("Maximum RAM memory size is 32KB, memory area reduced");
	}
	else if (RAM.length % 2048 != 0) {  // Real processor uses a RAM chips multiple of 2KB min
		var nRAM = new Uint8Array((Math.floor(RAM.length / 2048)+1)*2048);
		nRAM.set(RAM);
		RAM = nRAM;
		console.log(`The RAM size must be a multiple of 2KB, increasing the area to ${RAM.length / 1024}KB.`);
	}
}

function ROMbou() {
	if (ROM.length > 32768) {  // 32KB max size
		ROM = ROM.subarray(0, 32768);
		console.log("Maximum ROM memory size is 32KB, memory area reduced");
	}
	else if (ROM.length % 8192 != 0) {  // Real processor uses a ROM chips multiple of 8KB min
		var nROM = new Uint8Array((Math.floor(ROM.length / 8192)+1)*8192);
		nROM.set(ROM);
		ROM = nROM;
		console.log(`The ROM size must be a multiple of 8KB, increasing the area to ${ROM.length / 1024}KB.`);
	}
}

/* http://stackoverflow.com/questions/21797299/convert-base64-string-to-arraybuffer */

function base64ToArrayBuffer(base64) {
    var binary_string =  window.atob(base64);
    var len = binary_string.length;
    var bytes = new Uint8Array( len );
    for (let i = 0; i < len; i++)        {
        bytes[i] = binary_string.charCodeAt(i);
    }
    return bytes.buffer;
}

/* ---------- */

/* https://stackoverflow.com/questions/814613/how-to-read-get-data-from-a-url-using-javascript */

function parseURLParams(url) {
    var queryStart = url.indexOf("?") + 1,
        queryEnd   = url.indexOf("#") + 1 || url.length + 1,
        query = url.slice(queryStart, queryEnd - 1),
        pairs = query.replace(/\+/g, " ").split("&"),
        parms = {}, i, n, v, nv;

    if (query === url || query === "") return;

    for (i = 0; i < pairs.length; i++) {
        nv = pairs[i].split("=", 2);
        n = decodeURIComponent(nv[0]);
        v = decodeURIComponent(nv[1]);

        if (!parms.hasOwnProperty(n)) parms[n] = [];
        parms[n].push(nv.length === 2 ? v : null);
    }
    return parms;
}

/* ---------- */

function loadBinaryHTTP(urlBIN, callback, errCallback) {
	if (typeof urlBIN.substring == "undefined") urlBIN = urlBIN.toString();
	if (urlBIN.substring(0,5) != window.location.href.substring(0,5) && window.location.href[4] == "s") {
		urlBIN = "https" + urlBIN.substring(4)
	}
	
	var oReq = new XMLHttpRequest();
	oReq.open("GET", urlBIN, true);
	oReq.responseType = "arraybuffer";
	loadCounter++;
	oReq.onload = function (oEvent) {
		if (oReq.status != 200) {
			console.log(`Failed to load ${urlBIN.toString().split('/').pop()}! Error`, oReq.status);
			if(typeof errCallback == 'function') errCallback();
			return;
		}

		var arrayBuffer = oReq.response; // Note: not oReq.responseText
		if (arrayBuffer) {
			console.log(`File ${urlBIN.toString().split('/').pop()} loaded!`);
			if(typeof callback == 'function') callback(arrayBuffer);
		};
	};
	oReq.send(null);
}

function ramAutoInit() {
	uniquesPressed.push("init");

	setTimeout(function () {
		uniquesPressed.splice("init", 1);
		window.localStorage.setItem('mk_ram', btoa(String.fromCharCode.apply(null, RAM)));
	  }, 500)
}

function devicePower() {
	if (POWER) {
		PAN.panelStop();
		LCD.stopAnimating();
		LCD.clearScreen();
		DBG.debugStop();
		document.getElementById("stst").innerText = "Pause";
		document.getElementById("dstst").innerText = "Pause";

		document.getElementById("dbst").disabled = POWER;
		document.getElementById("dbsts").disabled = POWER;
		document.getElementById("dbbr").disabled = POWER;
		document.getElementById("stps").disabled = POWER;
		document.getElementById("brkp").disabled = POWER;
		document.getElementById("regist").disabled = POWER;
        document.getElementById("reged").disabled = POWER;
        document.getElementById("edreg").disabled = POWER;
		
		stopped = false;
	}
	else {
		MK85CPU = new CPU();
		startEmu();
		PAN.panelStart();
		DBG.debugStart();
	}

	document.getElementById("swi").setAttributeNS(null, "opacity", POWER ? 1 : 0);
	document.getElementById("stst").disabled = POWER;
	document.getElementById("rst").disabled = POWER;
	document.getElementById("dstst").disabled = POWER;
	document.getElementById("drst").disabled = POWER;
	document.getElementById("cspm").disabled = POWER;
	document.getElementById("rstm").disabled = POWER;

	document.getElementById("disu").disabled = !POWER;
	document.getElementById("dispu").disabled = !POWER;
	document.getElementById("disgo").disabled = !POWER;
	document.getElementById("disgob").disabled = !POWER;
	document.getElementById("dispd").disabled = !POWER;
	document.getElementById("disd").disabled = !POWER;
	document.getElementById("disr").disabled = !POWER;
	document.getElementById("dised").disabled = !POWER;
	document.getElementById("diss").disabled = !POWER;
	
	POWER = !POWER;
}

function startEmu() {
	glueCPU();
	LCD.timerCallback = function () {
		if(keysRead(PP)>0 || ((uniquesPressed.indexOf("stop")!=-1) && (PP&2)))
		{
//			if(uniquesPressed.indexOf("stop")!=-1) MK85CPU.flag_halt = true;
			MK85CPU.cpuctrl |= 0x0400;	// enable CPU clock if key in selected by PP rows is pressed
		}
		MK85CPU.steps = 1;
		for(var steps = 0; steps < MK85CPU.steps; steps++)
		{

			if(uniquesPressed.indexOf("stop")!=-1) {
				return; // looks like real MK stays "frozen" until STOP button will not be released
			}

			MK85CPU.step();

			if (BREAKPOINT<0) {
				panelSwState();
				BREAKPOINT = false;
				return;
			}
			
			if (SKIPBSTEP){SKIPBSTEP=false;}

			if(((MK85CPU.cpuctrl&0x1000)!=0) && !MK85CPU.ignorePowerOff) {
				console.log("Device was turned off by firmware (bit 12 in cpuctrl was set)!");
				devicePower();
				setTimeout(LCD.clearScreen.bind(LCD), 100); //clear screen after last update
				return;
			}

			if (typeof DEBUG_STEPS == "number") {
				MK85CPU.steps = DEBUG_STEPS;
			} else {
				MK85CPU.steps = (((MK85CPU.cpuctrl&0x0008)==0) && !MK85CPU.forceTurbo) ? SPEED_NORMAL : SPEED_TURBO;
			}
			
/*			if(MK85CPU.reg_u16[7] == 0x00f4) {
				console.log("HALT INTERRUPT");
				DEBUG = true;
			}*/
			if(MK85CPU.psw&MK85CPU.flags.H) console.log(MK85CPU.reg_u16[7].toString(16));
		}
			
	}
	LCD.animate(LCD_ANIMSPEED);
}

var PP = 0;	// CPU parallel port for now

// Attach CPU to everything else
function glueCPU() {
		
	var ramLastAddr = 0x8000+RAM.length;
	var romLastAddr = 0x0000+ROM.length;
	
	MK85CPU.readCallback = function (addr) {
		if((addr&0xfffe)==0x0100) return (keysRead(PP)>>((addr&1)?8:0))&0xff;
		if((addr<0x8000)&&(addr<romLastAddr)) return ROM[addr];
		if((addr>=0x8000)&&(addr<ramLastAddr)) return RAM[addr&0x7FFF]; // For any RAM size 
		// keyboard column regs
		return 0xFF;
	};

	MK85CPU.writeCallback = function (addr, byteVal) {
		if((addr>0x7f)&&(addr<0xe0)) {	// 0x80...0xDF is LCD contoller memory
			LCD.videoMemory[addr&0x7f] = byteVal;
			return;
		}
		if(addr==0xe0) {			// 0xe0 - LCD cursor register
			LCD.cursorReg = byteVal;
			return;
		}
		if(addr==0x102) {			// 0x102 - keyboard rows
			PP &= 0xff00;
			PP |= byteVal;
			return;
		}
		if(addr==0x103) {			// 0x102 - keyboard rows
			PP &= 0x00ff; 
			PP |= byteVal<<8;
			return;
		}
		if((addr>=0x8000)&&(addr<ramLastAddr)) { // For any RAM size 
			RAM[addr&0x7FFF] = byteVal;
			return;
		}
		return;
	};
}