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The 8080 CPU goes through the Bus interfaces for all memory accesses now. The PCjs CPU maintained its own copy of Bus memory structures and interfaces, partly for improved performance but also because some CPUs can turn on address translation (ie, paging), making separate interfaces a necessity. However, PC8080 has much lower performance requirements and no address translation requirements, so we should revert to the original Bus interfaces.

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This commit is contained in:
Jeff Parsons 2016-05-02 12:54:55 -07:00
commit a56f1cfde1
6 changed files with 376 additions and 434 deletions
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65
modules/pc8080/lib/bus.js
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@ -135,7 +135,7 @@ function Bus(parmsBus, cpu, dbg)
* [0]: registered function to call for every I/O access
*
* The registered function is called with the port address, and if the access was triggered by the CPU,
* the linear instruction pointer (LIP) at the point of access.
* the instruction pointer (IP) at the point of access.
*
* WARNING: Unlike the (old) read and write memory notification functions, these support only one
* pair of input/output functions per port. A more sophisticated architecture could support a list
@ -225,7 +225,6 @@ Bus.prototype.initMemory = function()
for (var iBlock = 0; iBlock < this.nBlockTotal; iBlock++) {
this.aMemBlocks[iBlock] = block;
}
this.cpu.initMemory(this.aMemBlocks, this.nBlockShift, this.nBusMask);
};
/**
@ -492,8 +491,6 @@ Bus.prototype.setMemoryBlocks = function(addr, size, aBlocks, type)
/**
* getByte(addr)
*
* For physical addresses only; for linear addresses, use cpu.getByte().
*
* @this {Bus}
* @param {number} addr is a physical address
* @return {number} byte (8-bit) value at that address
@ -520,8 +517,6 @@ Bus.prototype.getByteDirect = function(addr)
/**
* getShort(addr)
*
* For physical addresses only; for linear addresses, use cpu.getShort().
*
* @this {Bus}
* @param {number} addr is a physical address
* @return {number} word (16-bit) value at that address
@ -558,8 +553,6 @@ Bus.prototype.getShortDirect = function(addr)
/**
* setByte(addr, b)
*
* For physical addresses only; for linear addresses, use cpu.setByte().
*
* @this {Bus}
* @param {number} addr is a physical address
* @param {number} b is the byte (8-bit) value to write (we truncate it to 8 bits to be safe)
@ -587,8 +580,6 @@ Bus.prototype.setByteDirect = function(addr, b)
/**
* setShort(addr, w)
*
* For physical addresses only; for linear addresses, use cpu.setShort().
*
* @this {Bus}
* @param {number} addr is a physical address
* @param {number} w is the word (16-bit) value to write (we truncate it to 16 bits to be safe)
@ -627,6 +618,36 @@ Bus.prototype.setShortDirect = function(addr, w)
this.aMemBlocks[iBlock & this.nBlockMask].writeByteDirect(0, (w >> 8) & 0xff, addr + 1);
};
/**
* addMemBreak(addr, fWrite)
*
* @this {Bus}
* @param {number} addr
* @param {boolean} fWrite is true for a memory write breakpoint, false for a memory read breakpoint
*/
Bus.prototype.addMemBreak = function(addr, fWrite)
{
if (DEBUGGER) {
var iBlock = addr >>> this.nBlockShift;
this.aMemBlocks[iBlock].addBreakpoint(addr & this.nBlockLimit, fWrite);
}
};
/**
* removeMemBreak(addr, fWrite)
*
* @this {Bus}
* @param {number} addr
* @param {boolean} fWrite is true for a memory write breakpoint, false for a memory read breakpoint
*/
Bus.prototype.removeMemBreak = function(addr, fWrite)
{
if (DEBUGGER) {
var iBlock = addr >>> this.nBlockShift;
this.aMemBlocks[iBlock].removeBreakpoint(addr & this.nBlockLimit, fWrite);
}
};
/**
* saveMemory(fAll)
*
@ -745,7 +766,7 @@ Bus.prototype.addPortInputBreak = function(port)
* @this {Bus}
* @param {number} start port address
* @param {number} end port address
* @param {function(number,number)} fn is called with the port and LIP values at the time of the input
* @param {function(number,number)} fn is called with the port and IP values at the time of the input
*/
Bus.prototype.addPortInputNotify = function(start, end, fn)
{
@ -794,18 +815,18 @@ Bus.prototype.addPortInputWidth = function(port, size)
};
/**
* checkPortInputNotify(port, size, addrLIP)
* checkPortInputNotify(port, size, addrIP)
*
* @this {Bus}
* @param {number} port
* @param {number} size (1, 2 or 4)
* @param {number} [addrLIP] is the LIP value at the time of the input
* @param {number} [addrIP] is the IP value at the time of the input
* @return {number} simulated port data
*
* NOTE: It seems that parts of the ROM BIOS (like the RS-232 probes around F000:E5D7 in the 5150 BIOS)
* assume that ports for non-existent hardware return 0xff rather than 0x00, hence my new default (0xff) below.
*/
Bus.prototype.checkPortInputNotify = function(port, size, addrLIP)
Bus.prototype.checkPortInputNotify = function(port, size, addrIP)
{
var data = 0, shift = 0;
@ -827,7 +848,7 @@ Bus.prototype.checkPortInputNotify = function(port, size, addrLIP)
if (aNotify !== undefined) {
if (aNotify[0]) {
dataPort = aNotify[0](port, addrLIP);
dataPort = aNotify[0](port, addrIP);
if (dataPort === undefined) {
dataPort = maskPort;
} else {
@ -840,7 +861,7 @@ Bus.prototype.checkPortInputNotify = function(port, size, addrLIP)
}
else {
if (DEBUGGER && this.dbg) {
this.dbg.messageIO(this, port, null, addrLIP);
this.dbg.messageIO(this, port, null, addrIP);
if (this.fPortInputBreakAll) this.dbg.checkPortInput(port, size, dataPort);
}
}
@ -902,7 +923,7 @@ Bus.prototype.addPortOutputBreak = function(port)
* @this {Bus}
* @param {number} start port address
* @param {number} end port address
* @param {function(number,number)} fn is called with the port and LIP values at the time of the output
* @param {function(number,number)} fn is called with the port and IP values at the time of the output
*/
Bus.prototype.addPortOutputNotify = function(start, end, fn)
{
@ -951,15 +972,15 @@ Bus.prototype.addPortOutputWidth = function(port, size)
};
/**
* checkPortOutputNotify(port, size, data, addrLIP)
* checkPortOutputNotify(port, size, data, addrIP)
*
* @this {Bus}
* @param {number} port
* @param {number} size
* @param {number} data
* @param {number} [addrLIP] is the LIP value at the time of the output
* @param {number} [addrIP] is the IP value at the time of the output
*/
Bus.prototype.checkPortOutputNotify = function(port, size, data, addrLIP)
Bus.prototype.checkPortOutputNotify = function(port, size, data, addrIP)
{
var shift = 0;
@ -981,7 +1002,7 @@ Bus.prototype.checkPortOutputNotify = function(port, size, data, addrLIP)
if (aNotify !== undefined) {
if (aNotify[0]) {
aNotify[0](port, dataPort, addrLIP);
aNotify[0](port, dataPort, addrIP);
}
if (DEBUGGER && this.dbg && this.fPortOutputBreakAll != aNotify[1]) {
this.dbg.checkPortOutput(port, size, dataPort);
@ -989,7 +1010,7 @@ Bus.prototype.checkPortOutputNotify = function(port, size, data, addrLIP)
}
else {
if (DEBUGGER && this.dbg) {
this.dbg.messageIO(this, port, dataPort, addrLIP);
this.dbg.messageIO(this, port, dataPort, addrIP);
if (this.fPortOutputBreakAll) this.dbg.checkPortOutput(port, size, dataPort);
}
}