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Appendix A: I/O & the LED Display
A.1 General Notes about the I/O
* The digital I/O is available on CONN6 (15 pin Dsub).
* Digital Outputs
The outputs are opto-isolated 300mA 50V solid state relays. When
activated (status LED is on), they switch the OUTPUT x (x=1,2,3, or
4) to I/O VOLTAGE OV. Hence the load would normally be
connected between OUTPUT x and the I/O .
* Digital Inputs
The digital inputs are designed to work with either npn or contact
input devices. They are activated by an external device pulling INPUT
x (x=1,2,3,or 4) down to I/O VOLTAGE OV.
To work in this way an external IO (in the range
10-30V) must be present.
* Analog Output
The analog output signal is set by a 16 bit DAC and appears on pin12
of CONN6. The output is with respect to the LCIC_WIM board
ground
(
not
the I/O 0V). The board ground appears at
pin13 of CONN6. The analog output control is application dependent.
