Page 133 - Understanding Automotive Electronics

2735 | CH 4 Page 120 Tuesday, March 10, 1998 11:06 AM

4 MICROCOMPUTER INSTRUMENTATION AND CONTROL

Table 4.1
Mnemonic Operand Comment
Assembly Language
Mnemonics JMP (Address) Jump to new program location
JSR (Address) Jump to a subroutine
BRA (Offset) Branch using the offset
BEQ (Offset) Branch if accumulator is zero
BNE (Offset) Branch if accumulator is nonzero
BCC (Offset) Branch if carry bit is zero
BCS (Offset) Branch if carry bit is nonzero
BPL (Offset) Branch if minus bit is zero
BMI (Offset) Branch if minus bit is nonzero
RTS Return from a subroutine
a. Program Transfer Instructions

Mnemonic Operand Comment
LDA (Address) Load accumulator from memory
STA (Address) Store accumulator to memory
LDA # (Constant) Load accumulator with constant
LDS # (Constant) Load stack pointer with constant
STS (Address) Store stack pointer to memory
b. Data Transfer Instructions

Mnemonic Operand Comment
COM Complement accumulator (NOT)
AND (Address) AND accumulator with memory
OR (Address) OR accumulator with memory
ADD (Address) Add accumulator with memory
SUB (Address) Subtract accumulator with memory
AND # (Constant) AND accumulator with constant
OR # (Constant) OR accumulator with constant
SLL Shift accumulator left logical
SRL Shift accumulator right logical
ROL Rotate accumulator left
ROR Rotate accumulator right
c. Arithmetic and Logical Operations

120 UNDERSTANDING AUTOMOTIVE ELECTRONICS