TEWS TECHNOLOGIES Introduces Extended Temperature, High-Density TTL Level Digital I/O PMC Module

The TPMC685 is offered standard with extended temperature operation, rear I/O, and a 5 year manufacturers warranty. Software drivers for most major real-time operating systems are available.

The direction of the I/O lines on the TPMC685 is software programmable by port. Each port is built up using a TTL bus transceiver. Each line is protected against ESD and overvoltage. Software selectable pullup/pulldown resistors are available on all I/O lines. It is possible to read or write synchronously all 128 lines.

Each channel configured as an input can generate an interrupt, and signal edge handling is programmable to interrupt on either the rising and/or falling edge of the input signal. Interrupts can be enabled and disabled for each bit. An interrupt status register is provided for simplified interrupt source detection of each bit. To eliminate spikes and glitches, thereby keeping interrupts to a minimum, each port has its own user configurable input filter.

All outputs drive 5V TTL levels with up to 24mA.

The first 64 bits of TTL I/O are accessible via the front panel HD68 SCSI-3 type connector and the second 64 bits of TTL I/O via rear panel P14. TPMC685-11 provides 8 additional ground contacts on the P14 connector. These grounds reduce the number of Back-I/O lines to 56, but improve the signal integrity.

To deal with software faults, the TPMC685 provides a user configurable Watchdog timer. It can set all outputs in a user defined (save) state when the watchdog expires. Two Timers are included in the TPMC685 for easy implementation of equidistant input sampling or output setting.