Connect the ASP
Wiring, protocols, and data conversion formulas for ASP system communication
Overview
Communication with the ASP nodes is done via an RS485 interface. This can be a serial port interface or a digital data logger.
To confirm compatibility with your data logger, please contact Osprey Measurement Systems.
Wiring Guide
The ASP wiring configuration is as follows:
| Colour | Function |
|---|---|
| Red | 8-18V |
| Black | Ground (G) |
| Blue | RS485 A |
| White | RS485 B |
Addresses
Nodes can be addressed using their Modbus alias which starts at "1" from the node closest to the cable entry point and are numbered sequentially along the length of the ASP.
RS485 Protocols
Serial Configuration
ASP nodes communicate via RS485 using the following serial settings by default:
| Parameter | Value |
|---|---|
| Baud | 9600 |
| Data Bits | 8 |
| Parity | None |
| Stop Bits | 1 |
| Flow Control | None |
MODBUS RTU
MODBUS offers the most robust communication with the ASP nodes. A complete set of MODBUS registers can be found in the MODBUS Reference section.
Refer to the data logger manufacturer's literature for instructions on how to configure the device using Modbus RTU.
ASCII
The ASCII protocol offers a user-readable means of communicating with the ASP nodes, allowing the user to adjust common settings, take readings or troubleshoot the system using a laptop or Android mobile device.
For more information on using the ASCII interface, please refer to the ASCII Reference section.