Why latch position and fire triggers in hardware?

A camera or sensor has to fire at an exact position, and a software trigger is late by the time the PC polls the bus. The PCI-1274's FIFO compares the live encoder position and fires the trigger output in hardware at up to 1 kHz, so the inspection image is captured at the exact point the part passes — the timing a sorting line cannot get from a general-purpose I/O card.

The Advantech PCI-1274 is a four-axis PCI motion control card built on an FPGA, with multi-latch and compare-trigger functions, driving pulse-type servo or stepper motors with 1 Mpps output and reading 4 MHz quadrature encoders.

• 4 axes, 1 Mpps pulse, 2-axis linear interpolation
• 12 or 16-channel latch and compare trigger
• T-curve and S-curve velocity profiles
• Universal PCI, 16 home modes

Against a general I/O card, the PCI-1274 synchronises the trigger to the motion in hardware, which is what separates a sharp inspection image from a blurred one.