2.2.1 Output Triggers

The Signal Routing Port module contains special triggers on the outputs of each RWn signal routing port pin that can be used to trigger Interrupt-on-Change, DMA module and ADC module.

The Interrupt-on-Change for Signal Routing Ports is a separate IOCV interrupt vector independent of the Interrupt-on-Change for regular I/O ports (IOC interrupt vector). However, the operation of an IOCV interrupt is very similar to that of the IOC interrupt. The IOCWP and IOCWN registers select the type of transition on the RWn signal routing port pin that will trigger an interrupt (positive edge, negative edge, or both). The IOCWF register contains the individual interrupt flags for each RWn signal routing port pin. The logical OR of all the IOCWFn flags for all the Signal Routing Ports is available as the system-level IOCV interrupt. Refer to the “IOC – Interrupt-on-Change” chapter of the appropriate device data sheet for more information about the operation of IOCxP, IOCxN and IOCxF registers.

In addition to the IOCV interrupt, the individual IOCWFn interrupt flags are available as separate triggers to Start or Abort a DMA transaction (DMAnSIRQ and DMAnAIRQ registers) or to auto-start an ADC conversion (ADACT register) making the Signal Routing Port module more useful in a hardware state machine-based application. For the IOCWFn flags to properly trigger the DMA and/or the ADC, the IOCWP and IOCWN registers must be appropriately configured. See the “Types of Hardware Triggers” section in the “DMA – Direct Memory Access” chapter and the “Auto-Conversion Trigger” section in the “ADC – Analog-to-Digital Converter with Computation Module” chapter in the device data sheet for more information.