Author Topic: Digital Inputs on the PCI & PCIe PC WATCHDOG DB-25 Connector  (Read 1724 times)

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Digital Inputs on the PCI & PCIe PC WATCHDOG DB-25 Connector
« on: September 14, 2010, 14:56:16 »
The PCI and PCIe boards have 4 general purpose digital input pins on the 25 pin DSub connector. These are not used by the PCI PC Watchdog and are available to the user for exclusive use from their application program using the DLL API library.

These 4 inputs are connected to a CMOS inverter with 1.0K pull-up resistors connected to +5.0V and a 100K series resistor for protection.

When the PCI PC Watchdog powers up the inputs are usually pulled to +5.0V so the values in the digital input registers are set to zero (0) because of the inverters.

If you drive the input low to 0.0V (Ground) with a signal or with a dry contact closure, the value in the input register will read as one (1).

Do not exceed +5.0V or less than 0.0V on the inputs or damage may occur.

AntonioB

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Re: Digital Inputs on the PCI & PCIe PC WATCHDOG DB-25 Connector
« Reply #1 on: June 21, 2012, 04:40:27 »
I see therefore that these inputs are not intended to trigger the Watchdog Timer. Is it so?.

Can you give a couple of simple examples regarding the use of these four digital inputs which could result interesting for an unattended 24/7 PC application?