SN8P1700
8-bit micro-controller build-in 12-bit ADC
SONiX TECHNOLOGY CO., LTD
Page 45
Revision 1.93
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ADDRESSING MODE
OVERVIEW
The SN8P1700 provides three addressing modes to access RAM data, including immediate addressing mode, directly
addressing mode and indirectly address mode. The main purpose of the three different modes is described in the
following:
IMMEDIATE ADDRESSING MODE
The immediate addressing mode uses an immediate data to set up the location (MOV A, #I, B0MOV M,#I) in ACC or
specific RAM.
Immediate addressing mode
MOV
A, #12H
; To set an immediate data 12H into ACC
DIRECTLY ADDRESSING MODE
The directly addressing mode uses address number to access memory location (MOV A,12H, MOV 12H,A).
Directly addressing mode
B0MOV
A, 12H
; To get a content of location 12H of bank 0 and save in ACC
INDIRECTLY ADDRESSING MODE
The indirectly addressing mode is to set up an address in data pointer registers (Y/Z) and uses MOV instruction to
read/write data between ACC and @YZ register (MOV A,@YZ, MOV @YZ,A).
Example: Indirectly addressing mode with @YZ register
CLR
Y
; To clear Y register to access RAM bank 0.
B0MOV
Z, #12H
; To set an immediate data 12H into Z register.
B0MOV
A, @YZ
; Use data pointer @YZ reads a data from RAM location
; 012H into ACC.
MOV
A,
#01H
B0MOV
Y, A
; To set Y = 1 for accessing RAM bank 1.
B0MOV
Z, #12H
; To set an immediate data 12H into Z register.
B0MOV
A, @YZ
; Use data pointer @YZ reads a data from RAM location
; 012H into ACC.
MOV
A,
#0FH
B0MOV
Y, A
; To set Y = 15 for accessing RAM bank 15.
B0MOV
Z, #12H
; To set an immediate data 12H into Z register.
B0MOV
A, @YZ
; Use data pointer @YZ reads a data from RAM location 012H
; Into ACC.