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@@ -26,9 +26,13 @@ class Bank{ |
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} |
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} |
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class MMC{ |
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constructor(){ |
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this.__banks = []; |
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this.__addr = 0; |
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this.__bnkidx = 0; |
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} |
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get size(){ |
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@@ -39,10 +43,58 @@ class MMC{ |
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get banks(){return this.__banks.length;} |
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// TODO: Add a get/set for the memory address. This should handle banking and memory address offsets. |
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// TODO: Add a get/set for memory data at the current address. |
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// TODO: Add method for adding memory modules} |
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// TODO: Add a connection between a memory address and the triggering of bank switching. |
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get address(){return this.__addr;} |
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set address(a){ |
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if (a >= 0 && a < this.size){ |
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this.__addr = a; |
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offset = 0; |
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for (let b=0; b < this.__banks.length; b++){ |
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if (a >= offset && a < offset + this.__banks[b].mem.size){ |
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this.__bnkidx = b; |
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this.__banks[b].mem.address = a - offset; |
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break; |
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} else { |
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offset += this.__banks[b].mem.size; |
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} |
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} |
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} |
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} |
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get byte(){return (this.__banks.length > 0) ? this.__banks[this.__bnkidx].mem.byte : -1;} |
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set byte(b){ |
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if (this.__banks.length > 0){ |
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this.__banks[this.__bnkidx].mem.byte = b; |
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} |
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} |
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connectMemory(mem, addroff){ |
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addroff = (typeof(addroff) === 'number' && addroff >= 0) ? addroff : -1; |
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if (addroff < 0 || addroff === this.size){ |
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this.__banks.push(new Bank(mem)); |
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} else { |
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offset = 0; |
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for (let b=0; b < this.__banks.length; b++){ |
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if (addroff === offset){ |
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if (this.__banks[b].mem.size !== mem.size) |
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throw new RangeError("Memory modules assigned to the same bank must be the same byte size."); |
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this.__banks[b].addMemModule(mem); |
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offset = -1; |
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break; |
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} else { |
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offset += this.__banks[b].mem.size; |
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} |
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} |
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if (offset >= 0) |
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throw new RangeError("Cannot align memory module to bank at address " + addroff); |
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} |
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return this; |
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} |
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mmSwitchCallback(){ |
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return (function(byte){ |
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// TODO: Check the bits to determin which bank and bank index is being switched on. |
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}).bind(this); |
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} |
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} |
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module.exports = MMC; |