Model 720 | 72 Line Digital I/O
- 72 bi-directional TTL lines, programmable in banks of 8
- 64 lines have edge detection with interrupts
- 8 lines have input strobe and output enable control
- Output driver readback
Model 720 is a low-cost solution for interfacing a large number of discrete logic signals to Compact PCI computers. Its 72 I/O lines are software programmable as inputs or outputs in banks of eight lines.
64 of the lines can detect logic state changes. A flag is set in a 64-bit register for each input that changes state. The register may be polled to determine which inputs have changed state. The 720 may optionally generate an interrupt whenever state changes occur.
Eight of the 72 I/O channels have special functionality. When programmed as inputs they may be configured to latch input data upon command from an external strobe signal. When programmed as outputs, an external strobe signal can be used to tri-state/enable the outputs. For additional flexibility, the data direction of these special I/O lines is programmable in two 4-bit blocks.
The optional 720 adapter may be connected to as many as three solid-state relay boards. Each 720RB relay board accepts twenty-four industry standard relays.
|Number of I/O channels||72 bi-directional TTL|
|Update rate||5 MHz|
|Programmable I/O blocks||Eight 8-bit blocks and two 4-bit blocks|
|Source current per channel||12 mA|
|Sink current per channel||12 mA|
|I/O connector||80 pin|
|Compatible relay board||Model 720RB|
|Power supply requirements||5 V (at 200 mA)|
|Model 720 Instruction Manual||1.0.3||289 KB|