Met-Tilt Service |
The Met-Tilt interface allows the connection of one or more devices to a serial port. This method is commonly used to access a meteorological station and a tilt sensor. The devices must conform to a specific interface protocol as used by the Met3 sensor from Paroscientific, Inc. Such devices accept commands on their serial port input line and emit responses on their output line. Multiple devices can be connected in a serial port loop, output-to-input, to allow a single serial port on the NetRS to query multiple devices. The NetRS periodically emits commands to the first device in the loop. Data (including commands and results) which are not recognized by one device must be forwarded along the loop to subsequent devices. Eventually all results reach the serial port input on the NetRS.
The Met-Tilt service can be configured to send command strings on repeating schedules. For example, a system might want to record a temperature measurement every hour and a tilt measurement every four hours. The results from these commands will be placed in any Trimble T00-format or Binex-format files that are being logged by the NetRS. Results are also included in any active RT17 or Binex data streams.
IMPORTANT: The NetRS will only include Met-Tilt data in data files that are started after the sensor commands have been configured. Data logging files which are started before enabling the Met-Tilt interface will not have Met data included in them.
To configure the receiver to work with external sensors:
The Met-Tilt interface can be active on only one of the four serial ports. If Met-Tilt is selected for a second port then the previous port will be switched to PPP mode.
Transmission times for periodic commands will be aligned appropriately. For example, 30 minute commands will be sent on the exact hour and half hour marks. If multiple commands would be triggered at the same time then they will be executed sequentially with a delay of 10 seconds between them.
Command strings can contain any characters except spaces. A typical met sensor command might be:
*0100P9Sending that command to a Paroscientific Met3 sensor would result in a temperature, pressure and relative humidity measurement which would be formatted as:
$PASHS,XDR,P,1.0076789,B,DQ 51878,C,24.69,C,DQRHT003,H,42.3,P,DQRHT003This result would be encoded into data records in any T00 or Binex files being logged at the time. Likewise, the result would be encoded into any active RT17 or Binex output streams.