GMS81C1102 Datasheet, PDF (32/89 Pages) Hynix Semiconductor – 8-BIT SINGLE-CHIP MICROCONTROLLERS

GMS81C1102 / GMS81C1202
reduce program byte length by using 2 bytes PCALL in-
stead of 3 bytes CALL instruction. If it is frequently called,
it is more useful to save program byte length.
Table Call (TCALL) causes the CPU to jump to each
TCALL address, where it commences the execution of the
service routine. The Table Call service area spaces 2-byte
for every TCALL: 0FFC0_H for TCALL15, 0FFC2_H for
TCALL14, etc., as shown in Figure 12-5 .
Example: Usage of TCALL
LDA
#5
TCALL 0FH
:
:
;
;TABLE CALL ROUTINE
;
FUNC_A: LDA LRG0
RET
;
FUNC_B: LDA LRG1 ₂
RET
;
;TABLE CALL ADD. AREA
;
ORG 0FFC0H
DW FUNC_A
DW FUNC_B
;1BYTE INSTR UCTIO N
;INSTEAD OF 3 BYTES
;NOR M AL C ALL
1
;TCALL ADDRESS AREA
Address
0FF00H
0FFFFH
PCALL Area Memory
PCALL Area
(256 Bytes)
Address
0FFC0_H
C1
C2
C3
C4
C5
C6
C7
C8
C9
CA
CB
CC
CD
CE
CF
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
DA
DB
DC
DD
DE
DF
Program Memory
TCALL 15
TCALL 14
TCALL 13
TCALL 12
TCALL 11
TCALL 10
TCALL 9
TCALL 8
TCALL 7
TCALL 6
TCALL 5
TCALL 4
TCALL 3
TCALL 2
TCALL 1
TCALL 0 / BRK *
NOTE:
* means that the BRK software interrupt is using
same address with TCALL0.
Figure 12-5 PCALL and TCALL Memory Area
Jan. 2002 ver 2.0
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