What Are The Differences Between a PFI Line and an APFI Line?

Updated Nov 22, 2022

Issue Details

I recently upgraded my application from NI 60xxE (formerly E Series) to NI 62xx (formerly M Series), and noticed the use of the terminology "APFI" for trigger lines. When does triggering require use of a PFI line versus an APFI line? What are the differences between these triggering lines?


With NI 62xx M Series boards, the analog trigger line is now called APFI (analog programmable function input), while the digital triggering still occurs on the PFI lines. Whereas with NI 60xxE E Series boards, both analog and digital triggering may be performed with PFI 0. In other words, PFI 0 no longer doubles as a digital and analog trigger for M-series, as is the case for E-series.

There are M-series devices with two connectors, such as the 625x and 628x, that have an APFI line present on both connectors (APFI 0 and APFI 1). Either the APFI 0 or APFI 1 terminal can be used as an analog trigger, but not both at the same time. They exist on both lines to allow access to an APFI line on both connectors.