0 jmp 0 23    jump to 23, start of main
 1 jmp 0 2     jump to 2, start of mult
 2 inc 0 7     increment stack register by 7, secure space for overhead, x, y, z, and w
 3 lod 0 3     load x, x is a formal parameter of call by value type 
 4 lit 0 0     load literal 1
 5 opr 0 12    perform x>0?
 6 jpc 0 20    if false, jump to 20, end of if statement
 7 lod 0 3     load x
 8 lit 0 1     load literal 1
 9 opr 0 3     perform x-1
10 lod 0 4     load y, y is a formal parameter of call by value type
11 lda 0 6     load address of w, w is a formal parameter of call by address type
12 stp 0 0     store stack top to address of 3 words ahead, this is actual parameter &w
13 stp 0 0     store stack top to address of 3 words ahead, this is actual parameter y
14 stp 0 0     store stack top to address of 3 words ahead, this is actual parameter x-1
15 cal 1 2     call mult, this is a recursive call
16 lod 0 6     load w
17 lod 0 4     load y
18 opr 0 2     perform w+y
19 sto 0 6     store stack top to w
20 lod 0 6     load w
21 sid 0 5     store indirectly stack top to address given by z, z is parameter of call by address
22 opr 0 0     return to the address next to the calling point
23 inc 0 6     increment stack register by 6, secure space for overhead, a, b, and w
24 lit 0 3     load literal 3
25 sto 0 3     store stack top to a
26 lit 0 5     load literal 5
27 sto 0 4     store stack top to b
28 lod 0 3     load a
29 lod 0 4     load b
30 lda 0 5     load address of w
31 stp 0 0     store stack top to address of 3 words ahead, this is actual parameter &w 
32 stp 0 0     store stack top to address of 3 words ahead, this is actual parameter b
33 stp 0 0     store stack top to address of 3 words ahead, this is actual parameter a
34 cal 0 2     call mult from main, note the difference from the call at 15
35 lod 0 5     load w
36 wrt 0 0     write w
37 opr 0 0     return to operating system