Campbell CR10X, Instruction Manual, Page: 316 / 363

CR10X Reference Manual
C-6
44 - 40 HEX = 4 HEX. Or in decimal:
68 - 64 = 4.
Exponent is 4 decimal.
The binary equivalent of Data bytes 2 to 4 is: 11011001 10011001 10011010.
Summing all the fractional values:
2
-1
+ 2
-2
+ 2
-4
+ 2
-5
+ 2
-8
+ 2
-9
+ 2
-12
+ 2
-13
+ 2
-16
+ 2
-17
+ 2
-20
+ 2
-21
+ 2
-23
= 0.85000.
Using the estimate method to find the Mantissa = D9 99 9A HEX / 1 00 00 00 HEX
(or 14260634 / 16777216) which is 0.85000 decimal.
The value is then (+)0.85*2
4
which equals 13.60.
If appropriately requested by a J command, Final Storage data, if any, will
immediately follow the input location data. See section C.2 for a description of
how to decode Final Storage data in Campbell Scientific’s binary data format.
Final Storage data is limited to not more than 1024 bytes per K command.
The K command data is terminated with 7F 00 HEX (a unique binary format
code) followed by two signature bytes. See section C.3 for the meaning and
calculation of the signature bytes. The signature in this case is a function of all
bytes from the first time byte to the 7F 00 HEX bytes. Calculate the signature of
the bytes received and compare with the signature received to determine the
validity of the transmission.
C.2 Final Storage Format
CR10X data is formatted as either 2-byte Low Resolution or 4-byte High
Resolution values. The first two bytes of an output array contain a code noting the
start of the output array and the output array ID, followed by the 2- or 4-byte data
values. At the end of the data sent in response to the telecommunications F
command a 2-byte signature is sent (see below).
Representing the bits in the first byte of each two byte pair as ABCD EFGH (A is
the most significant bit, MSB), the byte pairs are described in the next section.
C.2.1 Low Resolution Format — D,E,F Not All Ones
Bits Description
A Polarity, 0 = +, 1 = -.
B, C Decimal locators as defined below.
D -H 13-bit binary value (D=MSB). Largest possible number without D,
plus E, and F all 1 is 7167, but Campbell Scientific defines the largest
second allowable range as 6999.
byte
The decimal locators can be viewed as a negative base 10 exponent with decimal
locations as follows:
Bits Decimal Location
B C (4 digits)
0 0 XXXX.
0 1 XXX.X
1 0 XX.XX
1 1 X.XXX