Michell Instruments Liquidew EExd, Руководство пользователя

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Liquidew EExd User’s Manual
72 97097 Issue 14.1, November 2019
APPENDIX G
Register Configuration I
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w
 
 
Val 1
Val 2
Val 1 & 2 are in BCD, therefore 10H = 10, 58H = 58 and 09H = 9 etc. As a result A to
F are not valid values.
Values for Cycle Time and Max Cool Time are in units of 5 mins.
Register Configuration J
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w r/w
 
 
Day or Hours Minutes or Month
Values in HEX i.e. 17th March = 1103H
Register Configuration K
– signed int
15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
r r r r r r r r r r r r r r r r
Value



Sign bit = 1 for –ve values (signed int)
7FFF = 32767
8000 = -32768
Register Configuration L
- Floating Point Representation
The humidity values for sensors 1 & 2 are represented in IEEE-754 single precision
floating point format, in order to cater for the wide range in the value of ppm
V
. This
format is ‘Big Ended’ which means that the High byte is at a lower address in memory
than the Lo byte, and is represented as such in the register memory map. The IEEE-754
format is shown below.
Bit 31
Sign bit
0 = +
1 = -
Bits 30 to 23
Exponent Field
Has a +127 bias value
Bits 22 to 0
mantissa
Decimal representation of binary
Where 1.0 ≤ value < 2.0