Phytec eGrabber-4plus, Руководство по оборудованию

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Driver Software
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PHYTEC Meßtechnik GmbH 2004 L-608e_4
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Controlling the I/O Pins
The eGrabber-4plus offers an externally available, transistor driven
I/O pin. Using control signals, this I/O pin is freely selectable as input
or output. Both of the following functions can be used to control the
I/O pin.
Instructions on how to attach devices to the I/)-Pin can be found in
section 1.6.
This function is not available for the eGrabber-2.
void Set_Ext_IO (WORD nDevNo, BYTE bData)
bData: Control value, 0 = CLOSE, 1 = HI-Z
This function controls the switch output of the port pin. The output
pin’s transistor operates as a switch against Ground. If the control
value is set to 0, the switch is closed and current is supplied to the I/O
pin.
If the control value is set to 1, then the transistor is disabled
(high ohm / switch opened).
For more information on the technical specifications for the I/O
output, please refer to section 1.2.
Note:
When starting the computer, the transistor is disabled (
HI-Z
).
Connecting an external pull-up resistor creates a logic „1“ signal. A
connected device, i.e. a relay, has no power (switched off).