MCF5282 External Signals

pin can also be configured as an output signal, MA0, to select the output of the external multiplexer.

This pin can also be configured as GPIO PQA0.

14.2.13.6 QADC Analog Input (AN53/MA1)

This PQA signal is the direct analog input AN53. When using external multiplexing this pin can also be configured as an output signal, MA1, to select the output of the external multiplexer.

This pin can also be configured as GPIO PQA1.

14.2.13.7 QADC Analog Input (AN55/TRIG1)

This PQA signal is the direct analog input AN55. This pin can also be configured as an input signal, TRIG1, to trigger the execution of one of the two queues.

This pin can also be configured as GPIO PQA3.

14.2.13.8 QADC Analog Input (AN56/TRIG2)

This PQA signal is the direct analog input AN56. This pin can also be configured as an input signal, TRIG2, to trigger the execution of one of the two queues.

This pin can also be configured as GPIO PQA4.

14.2.14 Debug Support Signals

These signals are used as the interface to the on-chip JTAG controller and also to interface to the BDM logic.

14.2.14.1 JTAG_EN

This input signal is used to select between multiplexed debug module and JTAG signals at reset. If JTAG_EN is low, the part is in normal and background debug mode (BDM); if it is high, it is in normal and JTAG mode.

14.2.14.2 Development Serial Clock/Test Reset (DSCLK/TRST)

Debug mode operation: DSCLK is selected. DSCLK is the development serial clock for the serial interface to the debug module. The maximum DSCLK frequency is 1/5 CLKIN.

JTAG mode operation: TRST is selected. TRST asynchronously resets the internal JTAG controller to the test logic reset state, causing the JTAG instruction register to choose the bypass instruction. When this occurs, JTAG logic is benign and does not interfere with normal MCF5282 functionality.

Although TRST is asynchronous, Motorola recommends that it makes an

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MCF5282 User’s Manual

MOTOROLA

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Motorola MCF5282, MCF5281 user manual Debug Support Signals