User's Manual

Speedway Revolution Installation and Operations Guide Octane 4.4

Appendix B: GPIO Details

Speedway Revolution includes a multipurpose I/O port that contains an RS-232

serial port, four opto-isolated inputs, four opto-isolated outputs, and a +5V

supply. You access these features through a DE15 connector mounted on the side

of the reader.

The four opto-isolated inputs have a range of 0–30V. The reader treats an input

of 0–0.8V as a logic 0, and an input of 3–30V as a logic 1. The reader has a per-

input debounce interval that is configurable via LLRP. (See the document titled

Octane LLRP for more information). This value dictates the minimum pulse width

of an input. Impinj recommends that external devices guarantee a minimum

pulse width of at least 100 milliseconds.

The reader also provides four opto-isolated outputs. For the GPIO outputs to

function, an external user supply must be connected between V+, and V-.

The maximum voltage for this supply is 30V. When the user configures a selected

GPIO output via LLRP to output logic 0, an isolated FET switch within the reader

effectively shorts that output to V- with a current sink capability of up to 200mA.

When the user configures a selected GPIO output to logic 1, the selected output

is pulled to V+ through a 10K resistor. If GPIO isolation is not required, the

reader provides a +5V supply and a ground pin on the DB-15 that can be

connected to V+ and V-.

Figure B.1 shows the detailed function of each pin of the GPIO DB-15 connector.

Figure B.1 DB-15 GPIO Port Functions

 Note: As described above, both the input and output pins are opto-isolated.