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First cut at PDP-10 byte instructions

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This commit is contained in:
Jeff 2017-03-02 23:10:24 -08:00 • committed by Jeff Parsons
commit 25aa95cec8
7 changed files with 396 additions and 276 deletions
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111
modules/pdp10/lib/cpuops.js
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@ -188,11 +188,27 @@ PDP10.opFSC = function(op, acc)
*/
PDP10.opIBP = function(op, acc)
{
this.opUndefined(op);
var w = this.readWord(this.regEA);
var p = (w / PDP10.OPCODE.P_SCALE) & PDP10.OPCODE.P_MASK;
var s = (w >> PDP10.OPCODE.S_SHIFT) & PDP10.OPCODE.S_MASK;
p -= s;
if (p < 0) {
p = 36 - s;
w++;
}
w = (p * PDP10.OPCODE.P_SCALE) + (s << PDP10.OPCODE.S_SHIFT) + (w & PDP10.OPCODE.PTR_MASK);
this.writeWord(this.regEA, w);
};
/**
* opILDB(0o134000)
* opILDB(0o134000): Increment Pointer and Load Byte
*
* From the DEC PDP-10 System Reference Manual (May 1968), p. 2-16:
*
* Increment the byte pointer in location E as explained above. Then retrieve a byte of S bits from the
* location and position specified by the newly incremented pointer, load it into the right end of AC,
* and clear the remaining AC bits. The location containing the byte is unaffected, the original contents
* of AC are lost.
*
* @this {CPUStatePDP10}
* @param {number} op
@ -200,11 +216,30 @@ PDP10.opIBP = function(op, acc)
*/
PDP10.opILDB = function(op, acc)
{
this.opUndefined(op);
/*
* We're called in two phases: phase 1 is with regEA containing the address of the pointer, and phase 2
* is with regEA containing the address of the bits to be loaded.
*
* We can implement this as a simple combination of opIBP() and opLDB(), but taking care that we only call
* opIBP() on phase 1.
*/
if (this.regPS < 0) {
//noinspection JSUnresolvedFunction
PDP10.opIBP.call(this, op, acc);
}
//noinspection JSUnresolvedFunction
PDP10.opLDB.call(this, op, acc);
};
/**
* opLDB(0o135000)
* opLDB(0o135000): Load Byte
*
* From the DEC PDP-10 System Reference Manual (May 1968), p. 2-16:
*
* Retrieve a byte of S bits from the location and position specified by the pointer contained in location E,
* load it into the right end of AC, and clear the remaining AC bits. The location containing the byte is unaffected,
* the original contents of AC are lost.
*
* @this {CPUStatePDP10}
* @param {number} op
@ -212,23 +247,67 @@ PDP10.opILDB = function(op, acc)
*/
PDP10.opLDB = function(op, acc)
{
this.opUndefined(op);
/*
* We're called in two phases: phase 1 is with regEA containing the address of the pointer, and phase 2
* is with regEA containing the address of the bits to be loaded.
*/
var w = this.readWord(this.regEA);
if (this.regPS < 0) {
this.regPS = w;
this.regRA = this.regEA | PDP10.OPCODE.I_BIT;
this.advancePC(-1);
return;
}
var p = (this.regPS / PDP10.OPCODE.P_SCALE) & PDP10.OPCODE.P_MASK;
var s = (this.regPS >> PDP10.OPCODE.S_SHIFT) & PDP10.OPCODE.S_MASK;
if (p + s <= 32) {
w = (w >> p) & ((1 << s) - 1);
} else {
w = Math.trunc(w / Math.pow(2, p)) % Math.pow(2, s);
}
this.writeWord(acc, w);
this.regPS = -1;
};
/**
* opIDPB(0o136000)
*
* From the DEC PDP-10 System Reference Manual (May 1968), p. 2-16:
*
* Increment the byte pointer in location E as explained above. Then deposit the right S bits of AC into
* the location and position specified by the newly incremented pointer. The original contents of the bits
* that receive the byte are lost, AC and the remaining bits of the deposit location are unaffected.
*
* @this {CPUStatePDP10}
* @param {number} op
* @param {number} acc
*/
PDP10.opIDPB = function(op, acc)
{
this.opUndefined(op);
/*
* We're called in two phases: phase 1 is with regEA containing the address of the pointer, and phase 2
* is with regEA containing the address of the bits to be stored.
*
* We can implement this as a simple combination of opIBP() and opDDB(), but taking care that we only call
* opIBP() on phase 1.
*/
if (this.regPS < 0) {
//noinspection JSUnresolvedFunction
PDP10.opIBP.call(this, op, acc);
}
//noinspection JSUnresolvedFunction
PDP10.opDPB.call(this, op, acc);
};
/**
* opDPB(0o137000)
* opDPB(0o137000): Deposit Byte
*
* From the DEC PDP-10 System Reference Manual (May 1968), p. 2-16:
*
* Deposit the right S bits of AC into the location and position specified by the pointer contained
* in location E. The original contents of the bits that receive the byte are lost, AC and the remaining
* bits of the deposit location are unaffected.
*
* @this {CPUStatePDP10}
* @param {number} op
@ -236,7 +315,23 @@ PDP10.opIDPB = function(op, acc)
*/
PDP10.opDPB = function(op, acc)
{
this.opUndefined(op);
/*
* We're called in two phases: phase 1 is with regEA containing the address of the pointer, and phase 2
* is with regEA containing the address of the bits to be stored.
*/
var w = this.readWord(this.regEA);
if (this.regPS < 0) {
this.regPS = w;
this.regRA = this.regEA | PDP10.OPCODE.I_BIT;
this.advancePC(-1);
return;
}
var p = (this.regPS / PDP10.OPCODE.P_SCALE) & PDP10.OPCODE.P_MASK;
var s = (this.regPS >> PDP10.OPCODE.S_SHIFT) & PDP10.OPCODE.S_MASK;
var b = (this.readWord(acc) % Math.pow(2, s)) * Math.pow(2, p);
w = (w - (w % Math.pow(2, p + s))) + b + (w % Math.pow(2, p));
this.writeWord(this.regEA, w);
this.regPS = -1;
};
/**