46.4.5 Initialization/Capture Register

The 32-bit general purpose Initialization/Capture (QEIxIC) register can be used to initialize the position counter and capture the contents of the position counter. The QEIxIC register can perform only one of these tasks at a time, but the mode of operation may be changed during operation. Typical application examples include:

• On power-up, the machine needs to orient itself to a known reference point. The QEIxIC register is loaded with the “home” position. The position counter is configured via the PIMOD bits to initialize the position counter on the first index event following a home event. The home and index events occur and the contents of the QEIxIC register are loaded into the Position Counter (POSxCNT) register.
• A user connects a “Touch Probe” to the machine via the “HOME” input to measure a previously machined item. The machine scans the item in a pattern, constantly moving the machine until a probe contact occurs. The probe contact causes the QEIxIC register to capture the position. The position information is then relayed to another computer for analysis.