NEC PD754144 User Manual
Page 262
CHAPTER 11 INSTRUCTION SET
262
User’s Manual U10676EJ3V0UM
Caution
The MOVT XA, @PCDE instruction usually references the table data in page where the instruction exists. If the
instruction is at address
××FFH, however, the table data in the next page is referenced instead of the table data in
the page where the instruction exists.
7
0
02FFH
0300H
Page 3
Page 2
Program memory
a
For example, if the MOVT XA, @PCDE instruction is located at position a in the above figure, the table data in
page 3, not page 2, specified by the contents of register pair DE is transferred to register pair XA.
Application example
To transfer the 16-byte data at program memory addresses 0
×F0H to 0×FFH to data memory addresses 30H to
4FH
SUB:
SEL
MB0
MOV
HL, #30H
; HL
←
30H
MOV
DE, #0F0H
; DE
←
F0H
LOOP:
MOVT
XA, @PCDE
; XA
←
table data
MOV
@HL, XA
; (HL)
←
XA
INCS
HL
; HL
←
HL+2
INCS
HL
INCS
E
; E
←
E+1
BR
LOOP
RET
ORG
0
×F0H
DB
××H, ××H, ...
; table data