rtd DM5816, User Manual

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DM5816/DM6816 RTD Embedded Technologies, Inc.
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External I/O Connections
Figure 2-1 shows I/O connector pinouts for P2, P3, and P6. Refer to these diagrams as you make your
I/O connections.
Fig. 2-1 – P2, P3, and P6 I/O Connector Pin Assignments
Connecting the Digital I/O
The DM5816 is designed for direct connection to industry standard opto-22 isolated I/O racks and
system modules. Each digital I/O line has a digital ground, as shown in Figure 2-1. For all digital I/O
connections, the high side of an external signal source or destination device is connected to the
appropriate signal pin on the I/O connector, and the low side is connected to the DIGITAL GND. A
cable to provide direct connection to opto-22 systems, the XO50, is available as an accessory from RTD.
Connecting the Timer/Counter I/O
External connections to the timer/counters on the DM5816 can be made by connecting the high side
of the external device to the appropriate signal pin on I/O connector P6 and the low side to a P6
DIGITAL GND.
Connecting the External Interrupt
The DM5816 can receive externally generated interrupt signals – EXT INT1, through I/O connector P2,
pin 2, and EXT INT2, through I/O connector P3, pin 2 – and route them to an IRQ channel through on-
board header connectors P14 and P4. Interrupt generation is enabled through software. When interrupts
are enabled, a rising or falling edge on the EXT INT line will cause the selected IRQ line to go high,