EM78808
8-bit Micro-controller
1 ꢂenable interrupt of DED output data
Bit 7 (VRSEL) : Reference voltage VR selection bit for Comparator
0/1 ꢂVR = VDD/VR = 2.0V, When this bit is set to “0”, V2_0 ref. circuit will be powered off.
2.0V ref. circuit is only powered on when this bit and RD page0 bit 7(CMPEN) are all set to “1”.
IOCF (Interrupt Mask Register)
7
6
5
4
3
2
1
0
RBF/STD FSK/CW
INT2
INT1
INT0
CNT2
CNT1
TCIF
Bit 0 ~ Bit 7 : Interrupt enable bits.
0/1 ꢂdisable interrupt/enable interrupt
VII.3 I/O Port
PCRD
P
R
Q
Q
D
CLK
PCWR
C
L
P
R
PORT
Q
Q
D
IOD
CLK
PDWR
PDRD
C
L
0
1
M
U
X
Fig.25 The circuit of I/O port and I/O control register
The I/O registers are bi-directional tri-state I/O ports. The I/O ports can be defined as "input" or "output"
pins by the I/O control registers under program control. The I/O registers and I/O control registers are both
readable and writable. The I/O interface circuit is shown in Fig.25
______________________________________________________________________________________________________________________________________________________
* This specification is subject to change without notice.
8/1/2004 (V3.1)
43
ELAN [ ELAN MICROELECTRONICS CORP ]
