Lufft CHM 15k Nimbus, Руководство пользователя

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Communication RS485 & Ethernet
46 Revision R09, November 2016
1 *=any character
According to the UUencode standard, lines containing raw data are organized as
follows:
1
st
line:
begin 644 YYYYMMDDhhmmss_[location]_[device].nc<CR><LF>
2
nd
line:
M********************************************************<CR><LF>
3
rd
line:
M********************************************************<CR><LF>
...
(n-2)
th
line:
M********************************************************<CR><LF>
(n-1)
th
line:
E************************************************* ***<CR><LF>
n
th
line:
end<CR><LF>
* stands for any UUencode character that falls within the hex range HEX 21 to
60.
“M” (HEX 4D) at the beginning of a data line designates the number of data
bytes in this line, equally UUencoded:
– 4D, when decoded, corresponds to the number HEX 2D = 45 decimal.
By 4/3-UUencode conversion, these 45 bytes are encoded in 60 (60=45/3 x 4)
ASCII characters following “M”, except for the last line where only the last bytes,
typically less than 45, are encoded.
The example above contains “E” (HEX 45, HEX 25=37 decimal, decoded) which
means that 37 bytes of raw data are following. As a consequence of 4/3-encod-
ing (rounded up to a multiple of four), however, they require 52 (52=(37/3
rounded) x 4) ASCII characters.
Byte
Value
1
Description
0-238 Same as in extended data telegram (for 3 cloud layers)
239 <CR> 0D HEX
240 <LF> 0A HEX
241-(eeee-5) Raw data in ASCII format (UUencode)
eeee-4
eeee-3
**
Checksum (two's complement of the sum of bytes 0 to
eeee, excluding bytes eeee-4 and eeee-3,expressed in
hex code)
eeee-2 <CR> 0D HEX
eeee-1 <LF> 0A HEX
eeee <EOT> 04 HEX
Table 12: Raw data telegram format