PD64A_15 Datasheet, PDF (13/66 Pages) Renesas Technology Corp – 4-BIT SINGLE-CHIP MICROCONTROLLERS FOR INFRARED REMOTE CONTROL TRANSMISSION

µPD64A, 65
Figure 2-4. Data Memory Configuration
R1n (Higher 4 bits) R0n (Lower 4 bits)
R0
R10
R00
R1
R11
R01
R2
R12
R02
R3
R13
R03
R4
R14
R04
R5
R15
R05
R6
R16
R06
R7
R17
R07
R8
R18
R08
R9
R19
R09
RA
R1A
R0A
RB
R1B
R0B
RC
R1C
R0C
RD
R1D
R0D
RE
R1E
R0E
RF
R1F
R0F
DP (refer to 2.6 Data Pointer (DP))
ASR (refer to 2.3 Address Stack Register (ASR (RF)))
2.6 Data Pointer (DP): 11 Bits
The ROM data table can be referenced by setting the ROM address in the data pointer to call the ROM contents.
The lower 8 bits of the ROM address are specified by R0 of the data memory; and the higher 3 bits by bits 4,
5, and 6 of the P3 register (CR0).
After reset, the pointer contents become “000H”.
Figure 2-5. Data Pointer Configuration
P3 register
b6
b5
b4
R10
R00
P3 DP10^Note DP9
DP8
DP7 DP6 DP5 DP4 DP3 DP2 DP1
DP0 R0
Note Set DP10 of the µPD64A to 0.
2.7 Accumulator (A): 4 Bits
The accumulator, which is a register consisting of 4 bits, plays a leading role in performing various operations.
After reset, the accumulator contents are left undefined.
Figure 2-6. Accumulator Configuration
A3
A2
A1
A0
A
Data Sheet U14380EJ3V0DS00
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