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The pointer address is a byte, the pointer size is a
word, thus allowing 64 Kbyte addressing space,
and requires 1 byte after the opcode.
5.1.6 Indirect Indexed (Short, Long)
This is a combination of indirect and short indexed
addressing modes. The operand is referenced by
its memory address, which is defined by the
unsigned addition of an index register value (X or
Y) with a pointer value located in memory. The
pointer address follows the opcode.
The indirect indexed addressing mode consists of
two sub-modes:
Indirect Indexed (Short)
The pointer address is a byte, the pointer size is a
byte, thus allowing 00 - 1FE addressing space,
and requires 1 byte after the opcode.
Indirect Indexed (Long)
The pointer address is a byte, the pointer size is a
word, thus allowing 64 Kbyte addressing space,
and requires 1 byte after the opcode.
Table
32.
Instructions
Supporting
Direct,
Indexed,
Indirect
and
Indirect
Indexed
Addressing Modes
5.1.7 Relative mode (Direct, Indirect)
This addressing mode is used to modify the PC
register value, by adding an 8-bit signed offset to it.
The relative addressing mode consists of two sub-
modes:
Relative (Direct)
The offset follows the opcode.
Relative (Indirect)
The offset is defined in memory, of which the ad-
dress follows the opcode.
Long and Short
Instructions
Function
LD
Load
CP
Compare
AND, OR, XOR
Logical Operations
ADC, ADD, SUB, SBC
Arithmetic Addition/subtrac-
tion operations
BCP
Bit Compare
Short Instructions Only
Function
CLR
Clear
INC, DEC
Increment/Decrement
TNZ
Test Negative or Zero
CPL, NEG
1 or 2 Complement
BSET, BRES
Bit Operations
BTJT, BTJF
Bit Test and Jump Opera-
tions
SLL, SRL, SRA, RLC,
RRC
Shift and Rotate Operations
SWAP
Swap Nibbles
CALL, JP
Call or Jump subroutine
Available Relative Direct/
Indirect Instructions
Function
JRxx
Conditional Jump
CALLR
Call Relative