The National Instruments 777557-01 PXI Counter/Timer Module, also known as the PXI-6602, is designed for use in PXI or compactPCI chassis as well as PCI bus compatible desktop computers. Utilizing the National Instruments MITE PCI interface, this module supports high-speed DMA operations, PCI burst transfers, and bus-master capabilities, enabling continuous, scatter-gather DMA without consuming host computer resources. This versatile module excels in applications involving encoder position measurement, event counting, period measurement, pulse width analysis, pulse train generation, and frequency measurement, featuring eight high-performance counter/timers and TTL/CMOS compatible digital I/O.

Enhanced efficiency in complex applications is achieved through the module's ability to manage three simultaneous high-speed DMA transfers. It operates with a power requirement of 0.5 to 1.5 A and provides an I/O connector (pin 1) that supports a maximum current of 1 A with a voltage range of +4.65 V to +5.25 V. I/O characteristics include a high-Z power-on state with mild pull-downs, pull-down currents ranging from 10 μA to 200 μA, and input impedance varying from 25 kΩ to 500 kΩ. The design features a 56 Ω onboard resistor and a 19 Ω TIO ASIC output impedance, delivering a total output impedance of 75 Ω, with hysteresis controlled by 300 mV Schmitt triggers. This module offers a static data transfer capability across 32 digital I/O channels, with no handshaking required.

The timing I/O is characterized by an impressive maximum count of 4,294,967,295 and a resolution of 32 bits. Data transfers can be conducted via interrupts or DMA, ensuring robust performance across various applications. The physical dimensions of the module are 16.0 cm x 10.0 cm (6.3 in x 3.9 in), and it is equipped with a 68-pin female SCSI-II type I/O connector. The maximum working voltage operates at ±11 V for channel-to-earth and ±22 V for channel-to-channel, categorized under Measurement Category I.