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Added P5 limitation

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VirtualColossus 2019-12-04 14:28:53 +00:00
parent bcafaebf77
commit b88a35cd14
1 changed files with 25 additions and 2 deletions
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27
src/core/lib/Colossus.mjs
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@ -60,6 +60,7 @@ export class ColossusComputer {
this.rotorPtrs = {};
this.totalmotor = 0;
this.P5Zbit = [0, 0];
}
@ -165,6 +166,10 @@ export class ColossusComputer {
*/
this.runQbusProcessingAddition();
// Store Z bit impulse 5 two back required for P5 limitation
this.P5Zbit[1] = this.P5Zbit[0];
this.P5Zbit[0] = this.ITAlookup[charZin].split("")[4];
// Step rotors
this.stepThyratrons();
@ -184,14 +189,32 @@ export class ColossusComputer {
let S1bPtr = this.Sptr[0]-1;
if (S1bPtr===0) S1bPtr = ROTOR_SIZES.S1;
// Get Chi rotor 5 two back to calculate plaintext (Z+Chi+Psi=Plain)
let X5bPtr=this.Xptr[4]-1;
if (X5bPtr==0) X5bPtr=ROTOR_SIZES.X5;
X5bPtr=X5bPtr-1;
if (X5bPtr==0) X5bPtr=ROTOR_SIZES.X5;
// Get Psi rotor 5 two back to calculate plaintext (Z+Chi+Psi=Plain)
let S5bPtr=this.Sptr[4]-1;
if (S5bPtr==0) S5bPtr=ROTOR_SIZES.S5;
S5bPtr=S5bPtr-1;
if (S5bPtr==0) S5bPtr=ROTOR_SIZES.S5;
const x2sw = this.limitations.X2;
const s1sw = this.limitations.S1;
const p5sw = this.limitations.P5;
// Limitation calculations
let lim=1;
if (x2sw) lim = this.rings.X[2][X2bPtr-1];
if (s1sw) {
lim = lim ^ this.rings.S[1][S1bPtr-1];
if (s1sw) lim = lim ^ this.rings.S[1][S1bPtr-1];
// P5
if (p5sw) {
let p5lim = this.P5Zbit[1];
p5lim = p5lim ^ this.rings.X[5][X5bPtr-1];
p5lim = p5lim ^ this.rings.S[5][S5bPtr-1];
lim = lim ^ p5lim;
}
// console.log(this.Mptr);