Motorola ColdFire MCF5281 - Manual (Page 210)

Edge Port Module (EPORT)
11-2 Freescale Semiconductor
Table 11-1. Edge Port Module Operation in Low-power Modes
In wait and doze modes, the EPORT module continues to operate as it does in run mode. It may be
configured to exit the low-power modes by generating an interrupt request on either a selected edge or a
low level on an external pin. In stop mode, there are no clocks available to perform the edge-detect
function. Only the level-detect logic is active (if configured) to allow any low level on the external
interrupt pin to generate an interrupt (if enabled) to exit stop mode.
NOTE
The input pin synchronizer is bypassed for the level-detect logic since no
clocks are available.
11.3 Interrupt/General-Purpose I/O Pin Descriptions
All pins default to general-purpose input pins at reset. The pin value is synchronized to the rising edge of
CLKOUT when read from the EPORT pin data register (EPPDR). The values used in the edge/level detect
logic are also synchronized to the rising edge of CLKOUT. These pins use Schmitt triggered input buffers
which have built in hysteresis designed to decrease the probability of generating false edge-triggered
interrupts for slow rising and falling input signals.
When a pin is configured as an output, it is driven to a state whose level is determined by the corresponding
bit in the EPORT data register (EPDR). All bits in the EPDR are high at reset.
Low-power Mode EPORT Operation Mode Exit
Wait Normal Any IRQx Interrupt at or above level in LPICR
Doze Normal Any IRQx Interrupt at or above level in LPICR
Stop Level-sensing Only Any IRQx Interrupt set for level-sensing at or
above level in LPICR
MCF5282 and MCF5216 ColdFire Microcontroller User’s Manual, Rev. 3