Capture Mode

Capture mode makes use of the 16-bit odd numbered timer resources (Timer1, Timer3, etc.) . When an event occurs on the capture source, the 16-bit CCPRx register captures and stores the 16-bit value of the TMRx register. An event is defined as one of the following and is configured by the MODE bits:

When a capture is made, the Interrupt Request Flag bit CCPxIF of the PIRx register is set. The interrupt flag must be cleared in software. If another capture occurs before the value in the CCPRx register is read, the old captured value is overwritten by the new captured value.

Important: If an event occurs during a 2-byte read, the high and low-byte data will be from different events. It is recommended while reading the CCPRxH:CCPRxL register pair to either disable the module or read the register pair twice for data integrity.

The following figure shows a simplified diagram of the capture operation.

Figure 1. Capture Mode Operation Block Diagram