file: autoimet_ops.html
13 Jul 2004


The AUTOIMET main CPU board (VMLOGR53) normally operates in RS232 mode.
See the AUTOIMET Functional Description for info on changing to RS485 operation as well as the RS485 note at the end of this document.

Refer to AUTOIMET Commands for full command descriptions.

Getting Started

Individual ASIMET modules may be connected and disconnected while the AUTOIMET logger is running. Each minute, as modules are polled, missing modules are flagged, and the STAT command will report comms failures during all but the final 15 seconds of the logging interval (see RI setting, typically 60 seconds). For example, if there is no response from the PRC module when the AUTOIMET logger polls, the STAT command will report "PRC failure" in its output message for the next 45 seconds; power to the module is also turned OFF during this time, and 15 seconds before the end of the interval, it is restored. Hopefully the module recovers for this next cycle; note that modules DO NOT produce "good" data values until they rollover their internal 60-second sampling intervals; thus, for example, a WND module will respond the first minute after it is connected to the AUTOIMET logger (so there will be no failure message for the next minute) but will not have good data until the next minute. This is normal; ALL ASIMET modules operate asynchronously on their individual internal real-time clocks.

Special Note:The HullCom/SST subsystem only updates the reported temperature once per hour; in addition, if it is powered up after the first 15 minutes of the hour as determined by its own internal real-time clock, it will only report 0.000 for temperature until the next hour rolls over and a new temperature is acquired. See HullCom/SST Sub-System Operations & Prep for details.


The AUTOIMET (like ASIMET) has a communications protocol based on the SAIL (Serial ASCII Interface Loop) protocol developed at Oregon State University. The module is interrogated by sending commands with the following format (always with capital letters and terminated with a RETURN <cr>):


The STAT command will display several lines of status info about the instrument. Note that unlike the ASIMET and VMCM2 series instruments, the AUTOIMET software does not use SAIL Addresses currently, just the preceding # character, and always a terminating RETURN (ASCII carriage return <cr>)

On power up, the AUTOIMET logger will always come up running and logging as last configured (the STAT command will indicate Sampling GO when the AUTOIMET logger is running).

NOTE that only a subset of the commands is available while the AUTOIMET logger is running. The H command will indicate which commands are available depending upon the GO / STOPPED state of the AUTOIMET logger.

Refer to AUTOIMET Commands document for full command descriptions.

RF Modem Console Option

For normal NOAA/SEAS operation, an RF Modem is connected to the AUTOIMET RS232 console connector, and power for the RF Modem is taken from the RF Modem power connector at P20 (Aux Port A). RF Modem power is normally supplied by the AUTOIMET Aux battery supply, rather than the Sensor or Main (i.e. logger CPU) power sources. The mating RF Modem is typically located at some distance on the ship's bridge.

Due to the high power consumption of the RF Modems, the battery-powered RF Modem located with the AUTOIMET system is power switched to come on several seconds before the transmission of the standard NOAA/SEAS broadcast message. This message is normally sent a 6 minute intervals; since the mating RF Modem at the bridge has ship's power, it is always ON and ready to receive the NOAA/SEAS message. A window of ON time for the AUTOIMET RF modem allows the use of the GPS command to send GPS time and position from the ship's bridge to the AUTOIMET system for storage with the MET records in the FLASH memory card. (default ON time is 15 seconds; set by ON parameter under the UOK command).

NOTE also that power for the console RF Modem will stay ON continuosly if the AUTOIMET logger is STOPped; BEWARE of the BATTERY POWER CONSUMPTION when in this mode. Typical consumption should be determined for each installation and battery size vs. ON time calculated (with a safety factor!!) accordingly. In system tests, 400 MA at 13.0 VDC has been noted for one manufacturer's RF modem, a 5.2 WATT power consumption.


Local GPS Option

The local GPS unit must run continuously, so it is important to insure that it runs on its own battery stack, with power provided via the AUTOIMET Aux battery supply (same supply as RF Modem option above), or via self-contained batteries in the GPS package. Typical consumption should be determined for each installation and battery size vs. ON time calculated (with a safety factor!!) accordingly. In system tests, 200 MA at 12.0 VDC has been noted for one manufacturer's GPS - that's about 2.5 watts continuous power consumption.


Deployment Quick Start

For the complete discussion of AUTOIMET system preparation for deployment, refer to the AUTOIMET System Prep document.

The important steps are:

RS232 to RS485 converters