MCF5282 External Signals

14.2.10.2 Receive Serial Data Input (URXD[2:0])

URXD[2:0] are the receiver serial data inputs for the UART modules. Data received on these pins is sampled on the rising edge of the serial clock source lsb first. When the UART clock is stopped for power-down mode, any transition on this pin restarts it.

The URXD[1:0] pins can be configured as GPIO ports PUA3 and PUA1. The URXD2 input is offered on 3 pins and is a secondary function of the EMDIO/GPIO port PAS5 pin, CANRX/GPIO port PAS3 pin, and SDA/GPIO port PAS1 pin.

14.2.10.3 Clear-to-Send (UCTS[1:0])

The UCTS[1:0] signals are the clear-to-send (CTS) inputs, indicating to the UART modules that they can begin data transmission.

The UCTS[1:0] inputs are each offered as secondary functions on four pins--DTIN2, DTOUT2, DTIN0 and DTOUT0.

14.2.10.4 Request-to-Send (URTS[1:0])

The URTS[1:0] signals are automatic request to send outputs from the UART modules. URTS[1:0] can also be configured to be asserted and negated as a function of the Rx FIFO level.

The URTS[1:0] outputs are each offered as secondary functions on four pins: DTIN3, DTOUT3, DTIN1 and DTOUT1.

14.2.11 General Purpose Timer Signals

These pins provide the external interface to the general purpose timer functions.

14.2.11.1 GPTA[3:0]

These pins provide the external interface to the timer A functions.

These pins can also be configured as GPIO PTA[3:0].

14.2.11.2 GPTB[3:0]

These pins provide the external interface to the timer B functions.

These pins can also be configured as GPIO PTB[3:0].

14.2.11.3 External Clock Input (SYNCA/SYNCB)

These pins are used to clear the clock for each of the two timers, and are provided as a means of synchronization to externally clocked or timed events.

MOTOROLA

Chapter 14. Signal Descriptions

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Motorola MCF5281, MCF5282 user manual General Purpose Timer Signals