em78p164n ELAN Microelectronics Corp, em78p164n Datasheet - Page 14

• Manufacturer Part Number: em78p164n
• Description: 8-bit Microcontroller With Otp Rom
• Manufacturer: ELAN Microelectronics Corp

EM78P164N
8-Bit Microcontroller with OTP ROM
8 •
5.1.4 R3 (Status Register)
Bit 7 (RST): Bit for reset type (read only)
Bits 6 ~ 5 (GP1 ~ 0): General purpose read/write bits.
Bit 4 (T): Time-out bit
Bit 3 (P): Power down bit.
Bit 2 (Z): Zero flag.
Bit 1 (DC): Auxiliary carry flag
Bit 0 (C): Carry flag
5.1.5 R4 (RAM Select Register)
Bits 7 ~ 6 are general-purpose read/write bits. See the Data Memory Configuration.
Bits 5 ~ 0 are used to select registers (Address: 10~3F) in the indirect addressing
mode.
5.1.6 R5 (Port 5)
Bits 7 ~ 6 (unused): unused bits, set to 0 all the time
Bits 5 ~ 0 (P55 ~ P50): I/O data registers, user can use the IOC5 to define each bit as
Bit 7
Bit 7
RST
0
Bit 6
Bit 6
GP1
0: Set to 0 if the device wakes up from other reset type.
1: Set to 1 if the device wakes up from sleep mode on a pin change.
Set to 1 with the "SLEP" and "WDTC" command, or during power up and
reset to 0 by WDT time-out.
Set to 1 during power-on or by a "WDTC" command and reset to 0 by a
"SLEP" command.
Set to "1" if the result of an arithmetic or logic operation is zero.
0
input/output
Bit 5
GP0
Bit 5
P55
Bit 4 and Bit 3 (T and P) are read only.
Bit 4
Bit 4
P54
(This specification is subject to change without further notice)
T
Note
Bit 3
Bit 3
P53
P
Product Specification (V1.4) 05.28.2010
Bit 2
Bit 2
P52
Z
Bit 1
Bit 1
P51
DC
Bit 0
Bit 0
P50
C