
4.1 Introduction
The PCD-810x card provides 24 isolated digital inputs (signal levels depending on the type
of card) and three 8-bit bidirectional digital ports.
All digital inputs (identified as DIN00÷DIN23) use the D-Sub 25 connector located on the
card bracket, three digital ports (identified as DIO0, DIO1 and DIO2) use header type
connectors located at the back edge of the card.
In case of the standard format card (ie. PCT-842x), the DIO0 port is accessed on the card
bracket via adapter cable PCE-8019 terminated with D-Sub 9 connector. Remaining two
ports (ie. DIO1 and DIO2) can be accessed via adapter cable PCE-1620 (card bracket with
D-Sub 9 connector), or other types from the PCE-16xx series adapter boards.
Note: Unlike the adapter cable PCE-8019, the PCE-16xx boards are not included in the
delivery package of the card.
In case of the low-profile format card (ie. PCD-810x/LP) all three ports DIO0, DIO1 and
DIO2 can be accessed via adapter cable PCE-8025/LP (low-profile card bracket with D-Sub
25 connector); there are currently no other option available.
Note: The PCE-8025/LP adaptor board is not included in the delivery package of the card.
The signal direction of DIO port (ie. input or output option) can be selected independ for
each 8-bit port (it is not possible to select direction individually for each of the eight signals
of one DIO port) from the user software.
The port direction and output data after computer is turned on or restarted are stored in the
on-board EEPROM memory and can modify by the software utility (by default, all ports are
set as input).
4.2 Description of digital inputs
All cards of the PCD-810x series contain 24 isolated digital inputs they differ from each
other only by signal levels and input connections.
The PCD-8104 card digital inputs work with HC/HCT/TTL levels and use HCTMOS circuits
providing high input impedance, very low leakage current and protection diodes. The
unconnected state of inputs represents the H logic level generated by pull-up resistors 10
kOhm against a voltage of 5 V, and the inputs can be therefore also used to direct
connecting of floating contacts.
Check the Appendix, Figure 3 for detail information.
The PCD-8105 card digital inputs support 24 V signals level and work with positive polarity
against the common rail (inputs are designed for PNP outputs).
Check the Appendix, Figure 4 for detail information.
Similar to PCD-8105 card, digital inputs of the PCD-8106 card support 24 V signals level, but
work with negative polarity against the common rail (inputs are designed for NPN outputs).
Check the Appendix, Figure 5 for detail information.
4. Digital Inputs and Ports
PCD-8104, PCD-8105, PCD-8106 User Guide
rev. 12.2015 I - 5