Atmel AT89C5132 Specification Sheet page 7

4173ES–USB–09/07
Table 7. UART Signal Description
Signal
Name Type Description
Receive Serial Data
RXD I/O RXD sends and receives data in serial I/O mode 0 and receives data in serial
I/O modes 1, 2 and 3.
Transmit Serial Data
TXD O TXD outputs the shift clock in serial I/O mode 0 and transmits data in serial I/O
modes 1, 2 and 3.
Table 8. SPI Controller Signal Description
Signal
Name Type Description
SPI Master Input Slave Output Data Line
MISO I/O When in master mode, MISO receives data from the slave peripheral. When in
slave mode, MISO outputs data to the master controller.
SPI Master Output Slave Input Data Line
MOSI I/O When in master mode, MOSI outputs data to the slave peripheral. When in
slave mode, MOSI receives data from the master controller.
SPI Clock Line
SCK I/O When in master mode, SCK outputs clock to the slave peripheral. When in
slave mode, SCK receives clock from the master controller.
SPI Slave Select Line
SS I
When in controlled slave mode, SS enables the slave mode.
Table 9. TWI Controller Signal Description
Signal
Name Type Description
TWI Serial Clock
When TWI controller is in master mode, SCL outputs the serial clock to the
SCL I/O
slave peripherals. When TWI controller is in slave mode, SCL receives clock
from the master controller.
TWI Serial Data
SDA I/O
SDA is the bidirectional Two Wire data line.
Table 10. A/D Converter Signal Description
Signal
Name Type Description
AIN1:0 I A/D Converter Analog Inputs
AREFP I Analog Positive Voltage Reference Input
Analog Negative Voltage Reference Input
AREFN I
This pin is internally connected to AVSS.
AT89C5132
Alternate
Function
P3.0
P3.1
Alternate
Function
P4.0
P4.1
P4.2
P4.3
Alternate
Function
P1.6
P1.7
Alternate
Function
-
-
-
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