Omega Engineering HH303 - Digital Output and Communication; RS232 Command Interface

Type K J Thermometer
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4.11 Digital Output:
The Digital Output is a 9600bps N 81 serial interface.
The RX is a 5V normal high input port.
The TX is a 5V normal high output port.
The command of Digital Output is list below.
RS232 command Function Remarks
K(ASC 4BH) Ask for model No. Send 4 bytes
H(ASC 48H) Hold button
T(ASC 54H) TIMER button
M(ASC 4DH) AVG/MAX/MIN button
N(ASC 4EH) Exit AVG/MAX/MIN mode
R(ASC 52H) REL button
C(ASC 43H)
°C/°F
button
A(ASC 41H) Inquire all encoded data Send encoded 8 byte
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Command K:
Return 4 bytes. For example, when sends command "K" to meter,
it will return "3","0","3", ASCII(13) .
(0x13) represent T1,- 199.9°C, The total byte number should be
7+1+7+1+5+chr(13)=22Bytes
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Command T:
Equivalent to one pushing on the HOLD button.
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Command M:
Equivalent to one pushing on the HOLD AVG/MAX/
MIN button and no message is returned.
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