Sutron Xpert2, Руководство по эксплуатации и обслуживанию, Страница: 317 / 336

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Data sensor
reading transmitted will be value * 10^RightDigits. The
string /// will be sent if the data was never measured
or had bad quality
Battery
voltage 1 This is the battery voltage measured prior to
making the transmission. The range of the number
will be -32 to +31 and can be converted to volts by
multiplying by 0.234 and adding 10.6 allowing a
range of 3.1 to 18.1 volts.
Six-Bit Binary Encoded Format
The six bit binary format is used to encode numbers into displayable ASCII characters. Notice
that fractional numbers cannot be represented, so for instance a battery voltage of 13.04 volts set
up with 2 right digits will be sent as 1304.

A 1 byte encoded number can range from -32 to +31.

A 2 byte encoded number can range from -2048 to +2047

A 3 byte encoded number can range from -131072 to +131071
Binary encoded numbers are always sent most significant bytes first. The number itself is broken
down into 6-bit digits, and each digit is placed in one byte of data. The number 64 (ASCII "@")
is added to each digit to make it fall within the range of displayable ASCII characters. The only
exception is that 127 (ASCII <DEL>) is sent as 63 (ASCII "?")
Example 1 . Encoding the number 10 in 1 byte:
Since 10 will fit in 6-bits we only have to add 64 which would yield 74. So the number 10
would appear as ASCII 74 or the letter "J".
Example 2 . Encoding the number 12345 in 3 bytes:
First we have to convert 12345 into binary in 6-bit pieces:
12345 (base 10) = 11 000000 111001 (base 2)
Now we can convert each piece back to base 10:
11 000000 111001 (base 2) = 3, 0, 57
Finally, we add 64 to each piece and convert to ASCII:
67, 64, 121 = ASCII "C@y"
Example 3 . Encoding the number -12345 in 3 bytes:
First we have to convert -12345 into two's complement 18-bit binary: -12345 (base 10) = 111100
111111 000111 (base 2)
Now we can convert each piece back to base 10: 111100 111111 000111 (base 2) = 60, 63, 7