Test-Ok eC-test-mate, Hardware Reference Manual

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outputs share the same test pins as digital inputs 101..104 making these pins 'bi-directional'.
Setting a '1' with the SET_DIGITAL command on the open drain outputs will activate the output. I.e. the
output will pulled to GND.
When the output is pulled up to a positive voltage, the output may seem inverted since setting a '1' via the
SET_DIGITAL command will result in a '0' on the output!
Note: due to the series resistor at the input pins, the open-drain outputs have this series resistor as well,
resulting in a voltage divider. This may cause unexpected behaviour is low resistance pull-up resistors are
present.
Associated test command(s):
• CONFIG_DIGITAL_GROUP
• SET_DIGITAL
• MAP
Bi-Directional Digital I/O
With the eC-test-mate Type I, it is possible to test up to 4 bi-directional digital signals.
As described in previous two sections, the 4 output bits of Group 102 are located on the same connector
locations as digital inputs 101..104. Since the outputs are open-collector outputs, the line can be left floating
by setting the output to '0'. A pull-up resistor shall be present on the UUT.