Eeprom Configuration Settings - DAVIS Vantage Pro Reference Manual

Example, calculating the CRC in the DMPAFT example above:
Old CRC Data byte
0x0000 0xC6
0xB98A 0xCE
0x8470 0xA2
0x34A4 0x03
If you continue processing the received CRC value of 0xE2B4 it will look like this:
Old CRC Data byte
0xE2B4 0xE2
0xB400 0xB4
The final CRC of zero indicates that the "packet" passed its CRC check.
XII. EEPROM configuration settings
There are two different ways to access data from the EEPROM. The commands "
" " provide a text based interface that you can use with a terminal emulation program, such
EEWR
as HyperTerminal. All numerical data is sent and received as ASCII strings that represent
hexadecimal numbers. You can read as many values as you want with one "
you can only write one byte of data for each "
The commands "
EEBRD
read or write, but the actual EEPROM data is send and received as binary bytes. You can read
and write as many bytes as you would like to in a single command.
Both read and written data includes a CRC code. A CRC is required for data written with the
" " command.
EEBWR
There are several EEPROM data locations that should not be written with the "
commands. These are either factory calibration values that should not be changed, or else they
are values that can be set from a different command. For example, use the "
set the ARCHIVE_PERIOD value, and the "
ELEVATION values. It is safe to read these EEPROM values.
The table below gives the addresses and sizes of the most useful EEPROM data values. The
address of each field is given both in decimal and in hex. Use the hex value in all "
commands. There is a supplemental list of the locations where the Vantage graph data is stored
in section XIV.
Table index
(0x00 ^ 0xC6) = 0xC6
(0xB9 ^ 0xCE) = 0x77
(0x84 ^ 0xA2) = 0x26
(0x34 ^ 0x03) = 0x37
Table index
(0xE2^ 0xE2) = 0x00
(0xB4^ 0xB4) = 0x00
" and " " use similar hex strings to specify what data you want to
EEBWR
BAR=
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Table Value New CRC
0xB98A (0x0000 ^ 0xB98A) = 0xB98A
0x0E70 (0x8A00 ^ 0x0E70) = 0x8470
0x44A4 (0x7000 ^ 0x44A4) = 0x34A4
0x46B4 (0xA400 ^ 0x46B4) = 0xE2B4
Table Value New CRC
0x0000 (0xB400 ^ 0x0000) = 0xB400
0x0000 (0x0000^ 0x0000) = 0x0000
" command.
EEWR
" command to set the BAR_CAL and
" and
EERD
" command, but
EERD
" or " "
EEWR EEBWR
" command to
SETPER
"
EE...