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362 Part 4 The instruction-set processor level: special-function processors

Section 4 Processors based on a programming language

COMMUNICATION LIST OPERATIONS
14 Copy s into communication list, saving 1L0.
15 Move s into communication list. Saving 1L0.
16 Move 1L0 into location of s, saving s.
17 Move 1L0 into location of s, destroying s.
18 Copy location of s into communication list, saving 1L0.
19 Create a new symbol in location of s, saving s.

SIGNALLING OPERATIONS
20 Turn signal on if s = 1L0, off if not.
21 Turn signal on if s = 1L0, off if not; delete 1L0.
22 Turn signal on if s is responsible, off if not.
23 Turn signal on.
24 Turn signal off.
25 Invert signal.
26 Copy signal into location of s.
27 Copy signal into location of s, saving s.
28 Set signal according to s.
29 Set signal according to 5; delete s.

LIST OPERATIONS
30 Replace s by the symbol designated by s, and turn signal on; if symbol doesn't exist (b = 10), leave s and turn signal off.
31 Replace s by the symbol in d of s and turn signal on; if symbol doesn't exist, leave s and turn signal off.
32 Replace s by the location of the next symbol after d of s and turn signal on (s replaced by "0, 4, (f, part of d of s)"); if next symbol does not exist, leave s and turn signal off.
33 Insert 1L0 before s (move symbol from communication list).
34 Insert 1L0 after s (move symbol from communication list).

APPENDIX 3 THE INTERPRETATION CYCLE
1. Fetch the current instruction according to the current instruction address (CIA) of the current CIA list.
2. Decode and execute the c operation:

If c = 3 replace d by d part of the word at address d, reduce c to c = 2 and continue. If c = 2 replace d by d part of the word at address d, reduce c to c = 1 and continue. If c = 1 put d in the address register and go to step 3.
If c = 0 put CIA in the address register and go to step 3.
If c = 4 replace c, d by the c, d parts of the word at address d and go to step 2.
If c = 5 mark CIA "incomplete," save it, set a new CIA = d and go to step 1.

3. Decode and execute the b operation: (Some of the b operations which affect the interpretation cycle follow.)

If b = 0 turn the signal on, delete CIA and go to step 4.
If b = 1 save CIA, set a new CIA = d part of s and go to step 1.
If b = 2 replace b, c, d by s and go to step 2.
If b = 3 replace CIA by the d part of s and go to step 1.
If b = 10 delete CIA.

If no CIA "pops up" turn signal off, delete CIA and go to step 4.
If "popped up" CIA is marked "incomplete" fetch the current instruction again, move 1L0 into address register and go to step 3.
Otherwise go to step 4.

4. Replace CIA by the f part of the current instruction and go to step 1.

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