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Added support for PDP-10 RAM images

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This commit is contained in:
Jeff Parsons 2017-02-26 20:37:16 -08:00 • committed by Jeff Parsons
commit aecd943c52
23 changed files with 583 additions and 632 deletions
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8
modules/pdp10/lib/cpustate.js
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@ -344,10 +344,10 @@ class CPUStatePDP10 extends CPUPDP10 {
}
/*
* Bits 0-22 (I,X,Y) contain what we call a "reference address" (R), which is used to calculate the
* "effective address" (E). To determine E from R, we must extract I, X, and Y from R, set E to Y,
* then add [X] to E if X is non-zero. If I is zero, then we're done; otherwise, we must set R to [E]
* and repeat the process.
* Bits 0-22 (I,X,Y) contain what we call a "reference address" (R), which is used to calculate an
* 18-bit "effective address" (E). To determine E from R, we must extract I, X, and Y from R, set E
* to Y, then add [X] to E if X is non-zero. If I is zero, then we're done; otherwise, we must set R
* to [E] and repeat the process.
*
* However, we don't actually repeat the process immediately; we need to treat each indirection as a
* separate decoding step, to ensure that the emulator can "breathe" periodically. So instead, we