ST7293C3B1 datasheet(34/69 Pages) STMICROELECTRONICS

34 / 69 page

34/69

ST7294

Indexed (no offset, short, long)

The required data byte to do the operation is found

by its memory address, which is defined by the un-

signed addition of an index register (X or Y) with

an offset which follows the op-code.

The indirect addressing mode consists of three

sub-modes:

Indexed (no offset) :

There is no offset, (no extra byte after the op-

code), but only allows 00.FF addressing space.

Indexed (short) :

The offset is a byte, thus require only one byte af-

ter the op-code, but only allow

00..1FE addressing space.

Indexed (long) :

The offset is a word, thus allowing 64Kbytes ad-

dressing space, but requires 2 bytes after the op-

code.

No Offset, Long and

Short Indexed Instruc.

Function

Load

Compare

AND, OR, XOR

Logical Operations

ADC, ADD, SUB, SBC

Arithmetic Additions/Sub-

stractions operations

BCP

Bit Compare

No Offset and Short

Indexed Inst. 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 Operations

SLL, SRL, SRA, RLC,

RRC

Shift and Rotate Operations

SWAP

Swap Nibbles

CALL, JP

Call or Jump subroutine

Indirect (short, long):

The required data byte to do the operation is found

by its memory address, located in memory (point-

er).

The pointer address follows the op-code. The indi-

rect addressing mode consists of two sub-modes:

Indirect (short) :

The pointer address is a byte, the pointer size is a

byte, thus allowing 00..FF addressing space, and

requires 1 byte after the op-code.

Indirect (long) :

The pointer address is a byte, the pointer size is a

word, thus allowing 64Kbytes addressing space,

and requires 1 byte after the op-code.

Available Long and

Short Indirect

Instructions

Fun ction