SPRUHZ7K August 2015 – April 2024 AM5706 , AM5708 , AM5716 , AM5718 , AM5718-HIREL
Each gpmc_wait input pin can generate an interrupt when a wait-to-no-wait transition is detected. Depending on whether the GPMC_CONFIG WAITxPINPOLARITY bits (where x = 0 to 2) is active low or active high, the wait-to-no-wait transition is a low-to-high external WAIT signal transition or a high-to-low external WAIT signal transition, respectively.
The wait transition pin detector must be cleared before any transition detection. This is done by writing 1 to the WAITxEDGEDETECTIONSTATUS bit (where x = 0 to 2) of the GPMC_IRQSTATUS register according to the gpmc_wait pin used for the NAND device-ready signal monitoring. To detect a wait-to-no-wait transition, the transition detector requires a wait active time detection of a minimum of two GPMC_FCLK cycles. Software must incorporate precautions to clear the wait transition pin detector before wait (busy) time completes.
A wait-to-no-wait transition detection can issue a GPMC interrupt if the WAITxEDGEDETECTIONENABLE bit in the GPMC_IRQENABLE register is set and if the WAITxEDGEDETECTIONSTATUS bit field in the GPMC_IRQSTATUS register is set.
The WAITMONITORINGTIME bit field does not affect wait-to-no-wait transition time detection.
It is also possible to poll the WAITxEDGEDETECTIONSTATUS bit field in the GPMC_IRQSTATUS register according to the gpmc_wait pin used for NAND device ready signal monitoring.