CSE 111, Fall 00, P88 Assembly Language

CSE 111, Fall 2000

P88 ASSEMBLY LANGUAGE

Last Update: 27 November 2000, 1:00 p.m.

Note: material is highlighted

memloc is a memory register
constant is any constant (usually an integer)
AX is the CPU's accumulator (or computing register)
IP is the CPU's instruction-pointer register
CF is the CPU's condition-flag register
"B" & "NB" are possible contents of the CF
(think of them as strings)
"label" is a label on a line of instruction
(i.e., a name given to an instruction)

Syntax Semantics

COPY memloc, AX memloc := AX

COPY AX, memloc/constant AX := memloc/constant

ADD AX, memloc/constant AX := AX + memloc/constant

SUB AX, memloc/constant AX := AX - memloc/constant

MUL AX, memloc/constant AX := AX * memloc/constant

DIV AX, memloc/constant AX := AX div memloc/constant

CMP AX, memloc/constant if AX < memloc/constant then CF := B
else CF := NB

JMP label IP := instruction with that label

JNB label if CF = NB then IP := instruction with that label

JB label if CF = B then IP := instruction with that label

memloc constant memloc := constant
(used only for initializing memloc)

IN AX readln(AX)

OUT AX writeln(AX)

HALT IP := -1

Syntax	Semantics
`COPY` memloc, `AX`	memloc := `AX`
`COPY AX`, memloc/constant	`AX` := memloc/constant
`ADD AX`, memloc/constant	`AX` := `AX +` memloc/constant
`SUB AX`, memloc/constant	`AX` := `AX -` memloc/constant
`MUL AX`, memloc/constant	`AX` := `AX ` memloc/constant*
`DIV AX`, memloc/constant	`AX` := `AX div` memloc/constant
`CMP AX`, memloc/constant	if `AX` < memloc/constant then `CF` := `B` else `CF` := `NB`
`JMP` label	`IP` := instruction with that label
`JNB` label	if `CF` = `NB` then `IP` := instruction with that label
`JB` label	if `CF` = `B` then `IP` := instruction with that label
memloc constant	memloc := constant (used only for initializing memloc)
`IN AX`	readln(`AX`)
`OUT AX`	writeln(`AX`)
`HALT`	`IP` := -1