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Movt xa, @pcxa, Movt xa, @bcde – NEC PD754144 User Manual

Page 263

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CHAPTER 11 INSTRUCTION SET

263

User’s Manual U10676EJ3V0UM

MOVT XA, @PCXA

Function: XA

ROM (PC

11-8

+XA)

Transfers the lower 4 bits of the table data in the program memory addressed when the lower 8 bits (PC

7-0

) of the

program counter (PC) are replaced with the contents of register pair XA, to the A register, and the higher 4 bits to

the X register.

The table address is determined by the contents of the PC when this instruction is executed.

The necessary data must be programmed to the table area in advance by using an assembler directive (DB

instruction).

The PC is not affected by execution of this instruction.

Caution

If an instruction exists at address ¥¥FFH, the table data of the next page is transferred, in the same manner as

MOVT XA, @PCDE.

MOVT XA, @BCDE

Function: XA

ROM (BCDE)

Transfers the lower 4 bits of the table data (8-bit) in the program memory addressed by the register B and the

contents of registers C, D, and E, to the A register, and the higher 4 bits to the X register.

However, in the

µPD754244, register B is invalid. Be sure to set register B to 0000B.

The necessary data must be programmed to the table area in advance by using an assembler directive (DB

instruction). The PC is not affected by execution of this instruction.

Example

B (0)

C

X

A

15 1211

8 7

4 3

0

Table data H

X

3

0

Table data L

A

3

0

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