IBM EM78P809N Specification page 28

EM78P809N
8-Bit Microcontroller
IOC6 ~ IOC9 − I/O Port Control Register
INTCR − INT Control Register ( Address : 0Bh )
Bit 7
INT1NR
Bit 7 ( INT1NR ) : INT1 noise reject time select
Bit 6 ( INT0EN ) : INT0 enable control
Bit 5 : Reserved
Bit 4 ~ Bit 3 ( INT3ES1 ~ INT3ES0) : INT3 edge select
INT3ES1
Bit 2 : Reserved
Bit 1 ( INT1ES ) : INT1 edge select
Bit 0 (TC2ES) : Timer/Counter 2 edge select.
24 •
"1" puts the relative I/O pin into high impedance, while "0" defines the relative
I/O pin as output.
IOC6 and IOC9 registers are both readable and writable.
Bit 6 Bit 5
INT0EN 0
INT1NR = "0" : Pulses less than 63/fc are eliminated as noise
INT1NR = "1" : Pulses less than 15/fc are eliminated as noise
INT0EN = "0" : General I/O
INT0EN = "1" : /INT0 pin
INT3ES0
0 0
0 1
1 0
1 1
INT1ES = "0" : Rising edge
INT1ES = "1" : Falling edge
TC2ES = "0" : Rising edge
TC2ES = "1" : Falling edge
Bit 4 Bit 3
INT3ES1 INT3ES0
Product Specification (V1.0) 07.26.2005
(This specification is subject to change without further notice)
Bit 2 Bit 1 Bit 0
0 INT1ES TC2ES
Edge Select
Rising
Falling
Both edge
Reserved