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45 lines
1.9 KiB
Plaintext
45 lines
1.9 KiB
Plaintext
Comments:
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R1 holds y, as described in the source code
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R2 holds a, as described in the source code
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R3 holds b, as described in the source code
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R4 holds n, as described in the source code
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R5 holds the output (sum), as described in the source code
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R6 holds the number 0xB (for jumping to the end of the program)
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R7 holds the number 0x6 (for jumping back)
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(0x0) LDA R1 ##MEMORY_LOCATION_OF_s## (loads the seed, s, into R1, which then becomes y as in the source code)
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(0x1) LDA R2 ##MEMORY_LOCATION_OF_a## (loads a into R2)
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(0x2) LDA R3 ##MEMORY_LOCATION_OF_b## (loads b into R3)
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(0x3) LDA R4 ##MEMORY_LOCATION_OF_n## (loads n into R4)
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(0x4) LDA R6 ##MEMORY_LOCATION_CONTAINING_0xA## (loads 0xB, memory location of program end to R6)
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(0x5) LDA R7 ##MEMORY_LOCATION_CONTAINING_0x6## (loads 0x6, memory location for jumping back)
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(0x6) JC4 R6 R4 (if R4, in this case, n, is equal to 0, then jump to end, STP)
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(0x7) MLA R1 R2 R3 (multiply and add, same as in the source code y=y*a+b)
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(0x8) ADD R5 R5 R1 (adds y to the sum, so that sum+=y, as in the source code)
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(0x9) SBO R4 R4 (decrease R4, i.e. n by one, so no infinite loops occur)
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(0xA) JMP R7 (jumps back to check whether n>0 and if so, repeats again)
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(0xB) STP
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Example that can be used with the instruction generator program:
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LDA R1 0
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LDA R2 1
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LDA R3 2
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LDA R4 3
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LDA R6 4
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LDA R7 5
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JC4 R6 R4
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MLA R1 R2 R3
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ADD R5 R5 R1
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SBO R4 R4
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JMP R7 R6
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STP
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Requires setting the following data memory location:
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Set location '0' to value of s;
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Set location '1' to value of a;
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Set location '2' to value of b;
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Set location '3' to value of n;
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Set location '4' to value of 0xB;
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Set location '5' to value of 0x6;
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