The ACCES I/O M.2-II-4 consists of a 2260/2280 sized M.2 Card that connects to a Mobile-ITX-sized, DB-37M Isolation Module via an included 9” cable. That module is designed to be easily panel-mounted in any application environment. It uses the high speed PCI Express bus to transfer digital data to and from the card. The digital I/O is compatible with 8255 PPI chips making it easy to program. This allows for simple and trouble-free migration from other ACCES PCI and PCI Express digital I/O cards, but also provides for advanced features enabled by the onboard FPGA logic.
The M.2-II family of cards are well suited to complex environments, mitigating otherwise challenging ground-loops, high-common-mode, and transient voltage spikes common in electrically-noisy industrial or factory locations. Individual channel-to-channel isolation allows every channel to be physically and electrically separated from the others. The broad voltage compatibility allows use in a wide range of applications.
The non-polarized inputs support both AC and DC, and configuration jumpers allow 4.7ms input filters to be enabled per-channel, as desired – required for AC use. The Isolated Inputs support voltages from 3 to 31 VDC/VAC RMS [40Hz to 10000Hz], as well as standard 12/24 AC control transformer signals.
Change of State (COS) detection and interrupt capabilities are designed to relieve software from polling routines that can consume valuable processing time. Each port can be programmed for detecting state changes on their lines, in which any changes of the enabled port's bits (low-to-high or high-to-low) will generate an IRQ. An ISR (interrupt service routine) then determines which bit changed state and clears the interrupt.
Rounding out the utility of this solution are the 4 LVTTL general purpose I/O lines, programmable as inputs or outputs in groups of 2 lines. These lines are pulled up to VCCIO via 10k ohm resistors, useful for monitoring dry contacts that don’t need isolation.