t6020m ATMEL Corporation, t6020m Datasheet - Page 22

• Manufacturer Part Number: t6020m
• Description: Low-current Microcontroller For Watchdog Function
• Manufacturer: ATMEL Corporation

3.2.2
This, and all other bidirectional ports include a bitwise
programmable Control Register (P5CR), which allows
the individual programming of each port bit as input or
output. It also opens up the possibility of reading the pin
condition when in output mode. This is a useful feature
for self testing and for serial bus applications.
The port pins can also be used as external interrupt inputs
(see figures 24 & 25). The interrupts (INT1 and INT6) can
be masked or independently configured to trigger on ei-
BP52
BP53
T6020M
22 (54)
Bidir. Port
Bidir. Port
IN_Enable
IN_Enable
Bidirectional Port 5
Data in
Data in
I/O Bus
I/O Bus
Master reset
IN enable
P5CR:
I/O–bus
(Data out)
P53M2 P53M1 P52M2 P52M1 P51M2 P51M1 P50M2 P50M1
P5DATy
D
S
Decoder
Q
Figure 21. Port 5 external interrupts
Figure 20. Bidirectional Port 5
Decoder
INT1
*
Mask options
ther edge. The interrupt configuration and port direction
is controlled by the Port 5 Control Register (P5CR). An
additional low resistance pull–up/–down transistor mask
option provides an internal bus pull–up for serial bus ap-
plications.
The Port 5 Data Register (P5DAT) is I/O mapped to the
primary address register of address ’5’h and the Port 5
Control Register (P5CR) to the corresponding auxiliary
register. The P5CR is a byte-wide register and is config-
ured by writing first the low nibble then the high nibble
(see section 2.1 ”Addressing peripherals”).
V DD
Decoder
INT6
*
*
*
V
DD
Decoder
Pull-up
Pull-down
*
*
V
DD
I/O–bus
V
DD
*
*
Static
Pull-up
BP5y
Static
Pull-down
Rev. A3, 02-Apr-01
Data in
IN_Enable
Data in
IN_Enable
Bidir. Port
Bidir. Port
13359
13764
BP51
BP50