PD17225_15 Datasheet, PDF (19/86 Pages) Renesas Technology Corp – 4-BIT SINGLE-CHIP MICROCONTROLLER FOR SMALL GENERAL-PURPOSE INFRARED REMOTE CONTROL TRANSMITTER

µPD17225, 17226, 17227, 17228
2.4.2 System registers (SYSREG)
The system registers are registers that are directly related to control of the CPU. These registers are mapped to
addresses 74H-7FH on the data memory and can be referenced regardless of bank specification.
The system registers include the following registers:
• Address registers (AR0-AR3)^Note
• Window register (WR)
• Bank register (BANK)^Note
• Memory pointer enable flag (MPE)
• Memory pointers (MPH, MPL)
• Index registers (IXH, IXM, IXL)
• General register pointers (RPH, RPL)
• Program status word (PSWORD)
Note The address register (AR3) and the bank register (BANK) are fixed to 0 in the µPD17225 and 17226.
Figure 2-5. Configuration of System Register
Address 74H 75H 76H 77H 78H 79H 7AH 7BH 7CH 7DH 7EH 7FH
Name
Address register
(AR)
Window Bank
register register
(WR) (BANK)
Index register
(IX)
Data memory
row address
pointer (MP)
General
register
pointer
(RP)
Program
status
word
(PSWORD)
IXH
IXM
Symbol AR 3 AR 2 AR 1 AR 0 WR BANK
IXL RPH RPL PSW
MPH MPL
Bit b3 b2 b1 b0 b3 b2 b1 b0 b3 b2 b1 b0 b3 b2 b1 b0 b3 b2 b1 b0 b3 b2 b1 b0 b3 b2 b1 b0 b3 b2 b1 b0 b3 b2 b1 b0 b3 b2 b1 b0 b3 b2 b1 b0 b3 b2 b1 b0
Data
(AR) ( µ PD17227, 17228)
000
(AR) ( µ PD17226)
0000
(AR) ( µ PD17225)
00000
(WR)
(BANK) _M
(IX)
0
0
0
*
P
E
0
0
0
*
(MP)
*
(RP) ^{B C C I}
000
CMY Z X
*
DP
E
Initial
Value
At
Reset
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Undefined 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Note *: This bit is fixed to 0 in the µPD17225 and 17226.
Data Sheet U12643EJ2V0DS00
17