Motorola MCF5282, MCF5281 user manual FlexCAN Signals, 14.2.9 I2C Signals, Uart Module Signals

Models: MCF5282 MCF5281

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MCF5282 External Signals

14.2.8 FlexCAN Signals

14.2.8.1FlexCAN Transmit (CANTX)

Controller Area Network Transmit data output. This pin can also be configured as GPIO PAS2.

14.2.8.2FlexCAN Receive (CANRX)

Controller Area Network Transmit data input. This pin can also be configured as GPIO PAS3.

14.2.9 I2C Signals

The I2C module acts as a two-wire, bidirectional serial interface between the MCF5282 and peripherals with an I2C interface (such as LCD controller, A-to-D converter, or D-to-A converter). Devices connected to the I2C must have open-drain or open-collector outputs.

14.2.9.1 Serial Clock (SCL)

This bidirectional open-drain signal is the clock signal for the I2C interface. Either it is driven by the I2C module when the bus is in the master mode or it becomes the clock input when the I2C is in the slave mode.

This pin can also be configured as GPIO PAS0 or UTXD2.

14.2.9.2 Serial Data (SDA)

This bidirectional open-drain signal is the data input/output for the I2C interface. This pin can also be configured as GPIO PAS1 or URXD2.

14.2.10 UART Module Signals

The signals in the following sections are used to transfer serial data between three UART modules and external peripherals.

14.2.10.1 Transmit Serial Data Output (UTXD[2:0])

UTXD[2:0] are the transmitter serial data outputs for the UART modules. The output is held high (mark condition) when the transmitter is disabled, idle, or in the local loopback mode. Data is shifted out, lsb first, on this pin at the falling edge of the serial clock source.

The UTXD[1:0] pins can be configured as GPIO ports PUA2 and PUA0. The UTXD2 output is offered on 3 pins and is a secondary function of the EMDC/ GPIO port PAS4 pin, CANTX/GPIO port PAS2 pin, and SCL/GPIO port PAS0 pin.

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MCF5282 User’s Manual

MOTOROLA

Page 306
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Motorola MCF5282, MCF5281 user manual FlexCAN Signals, 14.2.9 I2C Signals, Uart Module Signals