• 3U Eurocard form factor, CompactPCI compliant (PICMG 2.0 R3.0)
• On-board four 82C54 programmable timer/ counter chips
• Up to 12-CH 16-bit timer/counters
• 1-CH 32-bit cascaded timer
• On-board 8 MHz clock source
• Four programmable clock sources for each timer/counter
• Programmable de-bounce filters for external clock & external interrupt inputs
• Multiple programmable interrupt sources

Introduction
ADLINK cPCI-8554 series are 12-CH 16-bit timer/counter and digital I/O modules for PXI/CompactPCI form factor. These devices provide ten independent timer/counters and one cascaded 32-bit timer by default, and is configurable to twelve independent timer/counters. The clock source for each timer/counter can be software selected from the cascaded 32-bit timer, external clock source, timer/counter output of the last channel, and the on-board 8 MHz clock. The flexible architecture makes it easy to reconfigure the hardware; for example, up to ten timer/counters can be cascaded to form a 160-bit timer/counter. The hardware can also generate interrupts from either the external interrupt sources or the output of the cascaded 32-bit timer.