CS SR50A, Инструкция по эксплуатации

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Appendix D. RS-232 and RS-485 Operation
D-11
Inches: DDD.DD
000.00 output for no valid reading
QQQ
This data value is the optional quality value output. The quality value is always
a three-digit integer and varies from 152 to 600, where 600 is the poorest
quality.
TT.TT
This setting must be set to Off. The SR50A will output a –999.00 if the
Temperature Output option is set to ON .
VVVVV
This is the diagnostic output value. Each digit represents a pass or a fail on a
diagnostic test.
XVVVV
If X is a 1, then the ROM Memory has passed the signature test.
VXVVV
If X is a 1, then no watchdog errors have occurred.
VVXXX
The three digits XXX are for factory use and should always read 111.
CC
This is a two-character checksum of the data packet. The checksum is the two’s
complement of the data packet sum including control characters.
The Least significant byte is used resulting in a two-character checksum.
<STX> = &h02 (Hexadecimal)
<CR> = &h0D (Hexadecimal)
<LF> = &h0A (Hexadecimal)
<ETX> = &h03 (Hexadecimal)
The following is a sample packet with proper checksum:
<STX>33;1838;194;11011;2C<CR><LF><ETX>
SUM =
02+33+33+3B+31+38+33+38+3B+31+39+34+3B+31+31+30+31+31
+3B+0D+0A+03
=0x3D4
Use Last byte only (D4) and calculate two’s complement = 100 – D4 = 2C
<CR>
Carriage return character. 0x0d in hexadecimal or 13 in decimal
<LF>
Line feed character. 0x0a in hexadecimal or 10 in decimal
<ETX>
End of transmission character. 0x03 in hexadecimal or 3 in decimal