Adtec digital EN-91 / EN-91P (version 1.02.29) Manual - Manual (Page 37)

GPIO and Parport information
The GPIO port allows encoder stop / start control and TTL voltage output for
monitoring systems. TTL pin behavior by default is HI (3V) when encoding and LO (0V)
when not encoding. Logic of the TTL pin can be configured based upon video detection,
encode status, and manual override with the PP9 API command. Please view API details for
further configuration information.
The DVC Parport allows custom events to be programmed upon input pin voltage
change. It contains 4 available inputs for custom commands. Please contact technical
support for advanced usage in programming the parallel port.
GPIO Pinout
PIN Designation Function
1 NC No Connect
2 D3 reserved for future functionality
3 D2 RECORD ( start encoder ) ( input )
4 D1 STOP ( stop encoder ) ( input )
5 D0 reserved for future functionality
6 NC No Connect
7 5VDC +5V DC
8 GND ground
9 TTL Tally HI (3V) or LO(0V) based upon PP9
logic ( output )