Codec Tieline Gateway User Manual page 293

29 Appendix A: RS232 and Control Port Wiring
Product
Gateway 4
Gateway
8/16
Relays
The Gateway range of codecs uses one or two DB-25 connectors to facilitate the use of CMOS solid
state relays for the control of equipment. Operation functions can be configured using the Rules
panel in the HTML5 Toolbox Web-GUI.
Inputs
The input signal is referenced to chassis ground, i.e. the ground reference terminal on the
connector is connected the chassis. The input device is a high impedance CMOS device with a
330 ohm pull-up resistor to +5 volts.
Operation is as simple as joining the input pin to the ground terminal. This can be via a remote
relay contact or the open circuit collector of a transistor or FET. DO NOT feed voltages into the
inputs.
Outputs
CMOS field effect transistors switch a low impedance path between the two pins when
activated. These are opto-isolated and floating above ground. It is important to current-limit the
source as damage will result where the current exceeds 100mA peak-to-peak. No more than 48
volts peak-to-peak should be used as a safety precaution. The resistance of the CMOS element
is approximately 25 ohms in the ON state.
Control Port Pin-outs 1-8
A closing contact across Inputs 1-8 to Ground will provide a closing contact on remote codec
Outputs 1 to 8. If a Tieline codec supports multi-unicast connections to multiple codecs, a contact
closure will appear on each of the compatible (non-G3) remote codecs' corresponding contacts. I.e.
Input 1 shorted, Output 1 contacts on all connected codecs closed.
© Tieline Research Pty. Ltd. 2021
Feature Notification
Control Ports One DB-25 connector supporting 8 CMOS solid state relays for
the control of equipment, consisting of 8 relay closures and 8 opto-
isolated outputs.
Control Ports Two DB-25 connectors supporting 16 CMOS solid state relays for
the control of equipment, consisting of 16 relay closures and 16
opto-isolated outputs.
Codec Connector I/O 1-8
Pin
1
2
3
Gateway and Gateway 4 Manual v1.2
Female DB25
Pin Function
Output 1
Output 2
Output 3
293