Samsung KS57C2308 Manual page 38

ADDRESSING MODES
4-BIT ADDRESSING
Operand
Notation
DA Direct: 4-bit address indicated
by the RAM address (DA) and
the memory bank selection
@HL Indirect: 4-bit address indi-
cated by the memory bank
selection and register HL
@WX Indirect: 4-bit address indi-
cated by register WX
@WL Indirect: 4-bit address indi-
cated by register WL
:
NOTE "x" means don't care.
+ +
PROGRAMMING TIP — 4-Bit Addressing Modes
4-Bit Direct Addressing
1. If EMB = "0":
ADATA EQU
BDATA EQU
SMB
LD
SMB
LD
LD
2. If EMB = "1":
ADATA EQU
BDATA EQU
SMB
LD
SMB
LD
LD
3-8
Table 3-3. 4-Bit Direct and Indirect RAM Addressing
Addressing Mode
Description
46H
8EH
15
A,P3
0
ADATA,A
BDATA,A
46H
8EH
15
A,P3
0
ADATA,A
BDATA,A
EMB Flag Addressable
Setting Area
000H–07FH
0 F80H–FFFH
1 000H–FFFH
0 000H–0FFH
1 000H–FFFH
x 000H–0FFH
x 000H–0FFH
; Non-essential instruction, since EMB = "0"
; A (P3)
; Non-essential instruction, since EMB = "0"
; (046H) A
; (F8EH (LCON))
; A (P3)
; (046H) A
; (08EH) A
KS57C2308/P2308/C2316/P2316
Memory Hardware I/O
Bank Mapping
Bank 0
Bank 15 All 4-bit
addressable
peripherals
SMB = 0, 1,15 (SMB = 15)
Bank 0
SMB = 0, 1, All 4-bit
15 addressable
peripherals
(SMB = 15)
Bank 0
Bank 0
A
–
–
–