On the Subject of Assembly Code

Why are registers important, when you are already modifying them!

On the module, there are 3 displays. The left display will have 8 “codes”, the top display will have a description of what a “code” does, and the right display tells you the position of the list you are in.

The list on the left of the module is index-0.

To solve the module, multiply the number of AA batteries by 2 and add 1. Modulo 8 and add 1 again. If there is any Lines of code, Scripting, or Brainf---, the number is 0. This number is the “code” you are going to solve for in each stage, where the “code” is the 3–5 letter word on the left of the module and the 2nd column in the list below.

Refer to the list below to get the description. You can also use the 2 buttons to cycle through the descriptions on the top of the module.

After you find the description of the correct code, input it by pressing the description box on top and the next stage will happen. Do this for a total of 3 times to solve the module.

Index	Code	Meaning
0	AAA	ASCII adjust AL after addition
1	AAD	ASCII adjust AX before division
2	AAM	ASCII adjust AX after multiplication
3	AAS	ASCII adjust AL after subtraction
4	ADC	Add with carry
5	ADD	Add
6	AND	Logical AND
7	CALL	Call procedure
8	CBW	Convert byte to word
9	CLC	Clear carry flag
10	CLD	Clear direction flag
11	CLI	Clear interrupt flag

12	CMC	Complement carry flag
13	CMP	Compare operands
14	CMPSB	Compare bytes in memory
15	CMPSW	Compare words
16	CWD	Convert word to doubleword
17	DAA	Decimal adjust AL after addition
18	DAS	Decimal adjust AL after subtraction
19	DEC	Decrement by 1
20	DIV	Unsigned divide
21	ESC	Used with floating-point unit
22	HLT	Enter halt state
23	IDIV	Signed divide
24	IMUL	Signed multiply
25	IN	Input from port
26	INC	Increment by 1
27	INT	Call to interrupt
28	INTO	Call to interrupt if overflow
29	IRET	Return from interrupt
30	Jcc	Jump if condition
31	JCXZ	Jump if CX is zero
32	JMP	Jump
33	LAHF	Load FLAGS into AH register
34	LDS	Load pointer using DS
35	LEA	Load Effective Address
36	LES	Load ES with pointer
37	LOCK	Assert BUS LOCK# signal
38	LODSB	Load string byte
39	LODSW	Load string word

40	LOOP	Loop control
41	MOV	Move
42	MOVSB	Move byte from string to string
43	MOVSW	Move word from string to string
44	MUL	Unsigned multiply
45	NEG	Two’s complement negation
46	NOP	No operation
47	NOT	Negate the operand, logical NOT
48	OR	Logical OR
49	OUT	Output to port
50	POP	Pop data from stack
51	POPF	Pop FLAGS register from stack
52	PUSH	Push data onto stack
53	PUSHF	Push FLAGS onto stack
54	RCL	Rotate left (with carry)
55	RCR	Rotate right (with carry)
56	REPxx	Repeat MOVS/STOS/CMPS/LODS/SCAS
57	RET	Return from procedure
58	RETN	Return from near procedure
59	RETF	Return from far procedure
60	ROL	Rotate left
61	ROR	Rotate right
62	SAHF	Store AH into FLAGS
63	SAL	Shift Arithmetically left (signed shift left)
64	SAR	Shift Arithmetically right (signed shift right)
65	SBB	Subtraction with borrow
66	SCASB	Compare byte string
67	SCASW	Compare word string

68	SHL	Shift left (unsigned shift left)
69	SHR	Shift right (unsigned shift right)
70	STC	Set carry flag
71	STD	Set direction flag
72	STI	Set interrupt flag
73	STOSB	Store byte in string
74	STOSW	Store word in string
75	SUB	Subtraction
76	TEST	Logical compare (AND)
77	WAIT	Wait until not busy
78	XCHG	Exchange data
79	XLAT	Table look-up translation
80	XOR	Exclusive OR