CYASM ASSEMBLER USER'S GUIDE VERSION 1.77

7. Instruction Set
The following notation will be used throughout this section of the document:
acc Accumulator
expr expression
k operand value
X X register
ADD Add without Carry ADD
Syntax:
Operation:
ADD A, expr
acc ← acc + k
ADD A, [expr]
acc ← acc + [k]
ADD A, [X + expr] acc ← acc + [X + k]
Description:
Adds a value; k, [k] or [X+ k] to the contents of the accumulator and places the result in
the accumulator.
Condition Flags:
CF:
ZF:
Set if, treating the numbers as unsigned, the result > 255; cleared otherwise.
Set if the result is zero; cleared otherwise.
Source Machine Code Cycles
Format Opcode Operand
ADD A, expr 01h Immediate byte 4
ADD A, [expr] 02h Direct address byte 6
ADD A, [X+expr] 03h Offset byte 7
ADC Add with Carry ADC
Syntax:
ADC A, expr
ADC A, [expr]
ADC A, [X + expr]
Operation:
acc ← acc + k + cf
acc ← acc + [k] + cf
acc ← acc + [X + k] + cf
Description: Adds the content of the carry bit along with the contents of the accumulator to a value; k,
[k] or [X+ k] and places the result in the accumulator.
Condition Flags:
CF:
ZF:
Set if, treating the numbers as unsigned, the result > 255; cleared otherwise.
Set if the result is zero; cleared otherwise.
Source Machine Code Cycles
Format Opcode Operand
ADC A, expr 04h Immediate byte 4
ADC A, [expr] 05h Direct address byte 6
ADC A, [X+expr] 06h Offset byte 7
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