Milltronics InterRanger IR-200, Инструкция по эксплуатации

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PL-545 41 InterRanger IR-200
CHANGE PROGRAM PARAMETER VALUE
This message is used by the host computer to change the program parameter values stored in the Model IR-
200 Monitor. The message is formatted as follows:
Data Length: $04
Message Type: $06
Additional Data: Byte $02 = Parameter Number
Byte $03 = MSB of the Parameter
Value
Byte $04 = LSB of the Parameter
Value
Expected Reply: Acknowledge Message or Negative
Acknowledge Message
Parameter values to be transmitted must all be encoded as a 16 bit binary number, then transmitted as two
hexadecimal bytes in ASCII format. Any value which normally includes a decimal point (tank depth, relay set
point values, etc.) must be multiplied by 10, 100, or 1000 (as necessary) to remove the decimal point before
converting to a 16 bit hexadecimal number.
Examples: To transmit a tank depth (parameter number 1) of 11.2 feet, the host must transmit the
hexadecimal equivalent of 112, or $0070. The complete message to IR-200 number 1 would
be “M010406010070007C”.
To transmit a tank depth of 2.45 meters, the host must transmit the hexadecimal equivalent of
245, or $00F5. The complete message to IR-200 number 2 would be “M0204060100F50102”.
To transmit a speed of sound correction factor (parameter number $0F) of 1.180, the host
must transmit the hexadecimal equivalent of 1180, or $049C. The complete message to IR-
200 number 2 would be “M0204060F049C00BB”.
To transmit a GAIN CONTROL (parameter number $0B) value of 75%, the value would be
encoded as $004B. The complete message to analyzer number 1 would be
“M0104060B004B0061”.
Some program parameters, such as GAIN CONTROL and TANK DEPTH, may be changed by the host
computer while the Monitor is in either the RUN or PGM modes of operation. For these parameters, the new
value will take affect automatically when the IR-200 begins a new profile cycle. Other parameters, such as
DISPLAY FORMAT and ECHO PROFILE UPDATE RATE, should only be altered by the host computer when
the Monitor is in the PGM mode of operation. The “Change Mode” message should be used prior to any
change of these values to place the unit in the PGM mode. After the parameter value is changed, the
“Change Mode” message may be used again to restart the RUN mode. The table in Program Parameter
Numbers on page 42 indicates which parameters require this special handling.
CHANGE MODE
This message commands the Model IR-200 to change its current mode of operation to either the RUN or
PGM state.