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Hacked the Bus component to permit devices to access the actual memory map (better solution will be maintain two separate maps: one for the CPU and a separate map for device access)

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Jeff Parsons 2016-11-28 13:27:06 -08:00 • committed by Jeff Parsons
commit 375146f6bb
9 changed files with 733 additions and 698 deletions
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126
modules/pdp11/lib/bus.js
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@ -103,6 +103,9 @@ function BusPDP11(parmsBus, cpu, dbg)
this.nBlockMask = this.nBlockTotal - 1;
this.assert(this.nBlockMask <= BusPDP11.BlockInfo.num.mask);
this.iBlockIOPageDefault = ((this.addrTotal - BusPDP11.IOPAGE_LENGTH) & this.nBusMask) >>> this.nBlockShift;
this.iBlockIOPageActive = this.iBlockIOPageDefault;
/*
* aIOHandlers is an array (ie, a hash) of I/O notification handlers, indexed by address, where each
* entry contains an array:
@ -171,7 +174,6 @@ BusPDP11.IOPAGE_LENGTH = 0x2000; // ie, 8Kb
BusPDP11.IOPAGE_MASK = BusPDP11.IOPAGE_LENGTH - 1;
BusPDP11.UNIBUS_22BIT = 0x3C0000; /*017000000*/
BusPDP11.MAX_MEMORY = BusPDP11.UNIBUS_22BIT - 16384; // Maximum memory address (need less memory for BSD 2.9 boot)
BusPDP11.ERROR = {
RANGE_INUSE: 1,
@ -497,6 +499,7 @@ BusPDP11.prototype.setIOPageRange = function(nRange)
addr = (1 << nRange);
this.nBusMask = (addr - 1);
addr -= BusPDP11.IOPAGE_LENGTH;
this.iBlockIOPageActive = (addr & this.nBusMask) >>> this.nBlockShift;
this.aIOPrevBlocks = this.getMemoryBlocks(addr, BusPDP11.IOPAGE_LENGTH);
if (this.aIOPageBlocks) {
this.setMemoryBlocks(addr, BusPDP11.IOPAGE_LENGTH, this.aIOPageBlocks);
@ -922,17 +925,33 @@ BusPDP11.prototype.setMemoryBlocks = function(addr, size, aBlocks, type)
*/
BusPDP11.prototype.getByte = function(addr)
{
/*
* If bits 18-21 of addr are all set (which is implied by addr >= BusPDP11.UNIBUS_22BIT aka 0x3C0000),
* then we have a 22-bit address pointing to the top 256Kb range, so we must pass the address through the
* UNIBUS relocation map.
*/
if (addr >= BusPDP11.UNIBUS_22BIT) {
addr = this.cpu.mapUnibus(addr);
}
if (addr >= BusPDP11.UNIBUS_22BIT) addr = this.cpu.mapUnibus(addr);
return this.aMemBlocks[(addr & this.nBusMask) >>> this.nBlockShift].readByte(addr & this.nBlockLimit, addr);
};
/**
* getBlockDirect(addr)
*
* This checks for block requests matching the active IOPAGE block and redirects to the original block;
* conversely, if the request is for the default IOPAGE block, then the request is redirected to the active
* IOPAGE block.
*
* @this {BusPDP11}
* @param {number} addr is a physical address
* @return {MemoryPDP11}
*/
BusPDP11.prototype.getBlockDirect = function(addr)
{
var iBlock = (addr & this.nBusMask) >>> this.nBlockShift;
var block = this.aMemBlocks[iBlock];
if (iBlock == this.iBlockIOPageActive && this.aIOPrevBlocks.length) {
block = this.aIOPrevBlocks[0];
} else if (iBlock == this.iBlockIOPageDefault) {
block = this.aMemBlocks[this.iBlockIOPageActive];
}
return block;
};
/**
* getByteDirect(addr)
*
@ -944,17 +963,10 @@ BusPDP11.prototype.getByte = function(addr)
*/
BusPDP11.prototype.getByteDirect = function(addr)
{
/*
* If bits 18-21 of addr are all set (which is implied by addr >= BusPDP11.UNIBUS_22BIT aka 0x3C0000),
* then we have a 22-bit address pointing to the top 256Kb range, so we must pass the address through the
* UNIBUS relocation map.
*/
if (addr >= BusPDP11.UNIBUS_22BIT) {
addr = this.cpu.mapUnibus(addr);
}
this.fFault = false;
this.nDisableFaults++;
var b = this.aMemBlocks[(addr & this.nBusMask) >>> this.nBlockShift].readByteDirect(addr & this.nBlockLimit, addr);
if (addr >= BusPDP11.UNIBUS_22BIT) addr = this.cpu.mapUnibus(addr);
var b = this.getBlockDirect(addr).readByteDirect(addr & this.nBlockLimit, addr);
this.nDisableFaults--;
return b;
};
@ -968,14 +980,7 @@ BusPDP11.prototype.getByteDirect = function(addr)
*/
BusPDP11.prototype.getWord = function(addr)
{
/*
* If bits 18-21 of addr are all set (which is implied by addr >= BusPDP11.UNIBUS_22BIT aka 0x3C0000),
* then we have a 22-bit address pointing to the top 256Kb range, so we must pass the address through the
* UNIBUS relocation map.
*/
if (addr >= BusPDP11.UNIBUS_22BIT) {
addr = this.cpu.mapUnibus(addr);
}
if (addr >= BusPDP11.UNIBUS_22BIT) addr = this.cpu.mapUnibus(addr);
var off = addr & this.nBlockLimit;
var iBlock = (addr & this.nBusMask) >>> this.nBlockShift;
if (!PDP11.WORDBUS && off == this.nBlockLimit) {
@ -995,23 +1000,16 @@ BusPDP11.prototype.getWord = function(addr)
*/
BusPDP11.prototype.getWordDirect = function(addr)
{
/*
* If bits 18-21 of addr are all set (which is implied by addr >= BusPDP11.UNIBUS_22BIT aka 0x3C0000),
* then we have a 22-bit address pointing to the top 256Kb range, so we must pass the address through the
* UNIBUS relocation map.
*/
if (addr >= BusPDP11.UNIBUS_22BIT) {
addr = this.cpu.mapUnibus(addr);
}
var w;
var off = addr & this.nBlockLimit;
var iBlock = (addr & this.nBusMask) >>> this.nBlockShift;
this.fFault = false;
this.nDisableFaults++;
if (addr >= BusPDP11.UNIBUS_22BIT) addr = this.cpu.mapUnibus(addr);
var off = addr & this.nBlockLimit;
var block = this.getBlockDirect(addr);
if (!PDP11.WORDBUS && off == this.nBlockLimit) {
w = this.aMemBlocks[iBlock++].readByteDirect(off, addr) | (this.aMemBlocks[iBlock & this.nBlockMask].readByteDirect(0, addr + 1) << 8);
w = block.readByteDirect(off, addr) | (this.getBlockDirect(addr + 1).readByteDirect(0, addr + 1) << 8);
} else {
w = this.aMemBlocks[iBlock].readWordDirect(off, addr);
w = block.readWordDirect(off, addr);
}
this.nDisableFaults--;
return w;
@ -1026,14 +1024,7 @@ BusPDP11.prototype.getWordDirect = function(addr)
*/
BusPDP11.prototype.setByte = function(addr, b)
{
/*
* If bits 18-21 of addr are all set (which is implied by addr >= BusPDP11.UNIBUS_22BIT aka 0x3C0000),
* then we have a 22-bit address pointing to the top 256Kb range, so we must pass the address through the
* UNIBUS relocation map.
*/
if (addr >= BusPDP11.UNIBUS_22BIT) {
addr = this.cpu.mapUnibus(addr);
}
if (addr >= BusPDP11.UNIBUS_22BIT) addr = this.cpu.mapUnibus(addr);
this.aMemBlocks[(addr & this.nBusMask) >>> this.nBlockShift].writeByte(addr & this.nBlockLimit, b & 0xff, addr);
};
@ -1049,17 +1040,10 @@ BusPDP11.prototype.setByte = function(addr, b)
*/
BusPDP11.prototype.setByteDirect = function(addr, b)
{
/*
* If bits 18-21 of addr are all set (which is implied by addr >= BusPDP11.UNIBUS_22BIT aka 0x3C0000),
* then we have a 22-bit address pointing to the top 256Kb range, so we must pass the address through the
* UNIBUS relocation map.
*/
if (addr >= BusPDP11.UNIBUS_22BIT) {
addr = this.cpu.mapUnibus(addr);
}
this.fFault = false;
this.nDisableFaults++;
this.aMemBlocks[(addr & this.nBusMask) >>> this.nBlockShift].writeByteDirect(addr & this.nBlockLimit, b & 0xff, addr);
if (addr >= BusPDP11.UNIBUS_22BIT) addr = this.cpu.mapUnibus(addr);
this.getBlockDirect(addr).writeByteDirect(addr & this.nBlockLimit, b & 0xff, addr);
this.nDisableFaults--;
};
@ -1072,14 +1056,7 @@ BusPDP11.prototype.setByteDirect = function(addr, b)
*/
BusPDP11.prototype.setWord = function(addr, w)
{
/*
* If bits 18-21 of addr are all set (which is implied by addr >= BusPDP11.UNIBUS_22BIT aka 0x3C0000),
* then we have a 22-bit address pointing to the top 256Kb range, so we must pass the address through the
* UNIBUS relocation map.
*/
if (addr >= BusPDP11.UNIBUS_22BIT) {
addr = this.cpu.mapUnibus(addr);
}
if (addr >= BusPDP11.UNIBUS_22BIT) addr = this.cpu.mapUnibus(addr);
var off = addr & this.nBlockLimit;
var iBlock = (addr & this.nBusMask) >>> this.nBlockShift;
if (!PDP11.WORDBUS && off == this.nBlockLimit) {
@ -1102,23 +1079,16 @@ BusPDP11.prototype.setWord = function(addr, w)
*/
BusPDP11.prototype.setWordDirect = function(addr, w)
{
/*
* If bits 18-21 of addr are all set (which is implied by addr >= BusPDP11.UNIBUS_22BIT aka 0x3C0000),
* then we have a 22-bit address pointing to the top 256Kb range, so we must pass the address through the
* UNIBUS relocation map.
*/
if (addr >= BusPDP11.UNIBUS_22BIT) {
addr = this.cpu.mapUnibus(addr);
}
var off = addr & this.nBlockLimit;
var iBlock = (addr & this.nBusMask) >>> this.nBlockShift;
this.fFault = false;
this.nDisableFaults++;
if (addr >= BusPDP11.UNIBUS_22BIT) addr = this.cpu.mapUnibus(addr);
var off = addr & this.nBlockLimit;
var block = this.getBlockDirect(addr);
if (!PDP11.WORDBUS && off == this.nBlockLimit) {
this.aMemBlocks[iBlock++].writeByteDirect(off, w & 0xff, addr);
this.aMemBlocks[iBlock & this.nBlockMask].writeByteDirect(0, (w >> 8) & 0xff, addr + 1);
block.writeByteDirect(off, w & 0xff, addr);
this.getBlockDirect(addr + 1).writeByteDirect(0, (w >> 8) & 0xff, addr + 1);
} else {
this.aMemBlocks[iBlock].writeWordDirect(off, w & 0xffff, addr);
block.writeWordDirect(off, w & 0xffff, addr);
}
this.nDisableFaults--;
};
@ -1246,8 +1216,8 @@ BusPDP11.prototype.restoreMemory = function(a)
/**
* getMemorySize(type)
*
* NOTE: The original pdp11.js defined MAX_MEMORY as IOBASE_UNIBUS - 16384, where IOBASE_UNIBUS
* is 4Mb less 256Kb, and then it subtracted another 16Kb so that BSD 2.9 could boot.
* NOTE: The original pdp11.js defined a constant named MAX_MEMORY equal to UNIBUS_22BIT - 16384,
* where UNIBUS_22BIT is 4Mb less 256Kb, from which it then subtracted another 16Kb "for BSD 2.9 boot."
*
* @this {BusPDP11}
* @param {number} type is one of the MemoryPDP11.TYPE constants (only RAM is currently supported)