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value (xx):
• xx=06 EC range
• xx=07 TDS range
• xx=08 NaCl range
The instrument sends the “ACK” (6) character every time a command is
recognized and a “NAK” (21) character for invalid commands.
COMMANDS REQUIRING AN ANSWER
RAS
Causes the instrument to send a complete set of readings in
according with the current range:
• Conductivity and temperature reading on EC range.
• TDS and temperature reading on TDS range.
• NaCl and temperature reading on NaCl range.
The answer string contains:
• Meter mode (2 chars):
• 06 - EC range
• 07 - TDS range
• 08 - NaCl range
• Meter status (2 chars of status byte): represents a 8
bit hexadecimal encoding.
• 0x40 - TDS unit (0=ppm, 1=g/L)
• 0x20 - EC unit (0=
µ
S, 1=mS)
• 0x10 - temperature probe is connected
• 0x01 - new GLP data available
• 0x02 - new SETUP parameter
• Reading status (1 char): R - in range, O - over
range, U - under range.
• The reading (corresponding to the selected range) -
7 ASCII chars, including sign and decimal point.
• Temperature reading - 7 ASCII chars, with sign and
two decimal points, always in ºC.
MDR
Requests the instrument model name and firmware code.
GLP
Requests the calibration data record.
The answer string contains:
• GLP status (1 char): represents a 4 bit hexadecimal
encoding.
• 0x04 - EC calibration available
• 0x08 - NaCl calibration available