R3 And R3Io Register - Abov MC80F0304 User Manual

R2 Data Register
R2
R27 R26 R25 R24 R23 R22 R21
R2 Direction Register
R2IO
R2 Pull-up
Selection Register
PU2
R2 Open Drain
Selection Register
R2OD

9.4 R3 and R3IO register

R3 is a 6-bit CMOS bidirectional I/O port (address 0C6
I/O pin (except R35) can independently used as an input or an
output through the R3IO register (address 0C7
only port. When R30 through R35 pins are used as input ports, an
on-chip pull-up resistor can be connected to them in 1-bit units
with a pull-up selection register 3 (PU3). R30 through R34 pins
can be used to open drain output port by setting the corresponding
bit of the open drain selection register 1 (R3OD).
In addition, Port R3 is multiplexed with alternate functions. R30
R31,and R32 can be used as ADC input channel 13,14 and 15 by
November 4, 2011 Ver 2.12
ADDRESS: 0C4
H
RESET VALUE: 00
H
R20
Input / Output data
ADDRESS: 0C5
H
RESET VALUE: 00
H
Port Direction
0: Input
1: Output
ADDRESS: 0FE
H
RESET VALUE: 00
H
Pull-up Resister Selection
0: Disable
1: Enable
ADDRESS: 0CA
H
RESET VALUE: 00
H
Open Drain Resister Selection
0: Disable
1: Enable
). Each
H
). R35 is an input
H
setting ADCM to enable ADC and select channel 13,14 and 15.
Port Pin
R30 AN13 (ADC input channel 13)
R31 AN14 (ADC input channel 14)
R32 AN15 (ADC input channel 15)
R33, R34 and R35 is multiplexd with X
.
MC80F0304/08/16
Alternate Function
, X , and RESET pin
IN OUT
49