Elnec BeeHive304, Руководство пользователя

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Elnec s. r. o.
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Tab Main checksum options allow you to set mode of Automatic checksum calculator.
(*2)
group Custom address range for main checksum
Enabled - user defined addresses are used to calculate checksum of buffer data,
otherwise, if Disabled , global Buffer start and Buffer end address is used for
calculation of checksum of buffer data
Fields From address and To address are used to enter address range for main
checksum calculation. Addresses are used only when checkbox Enabled is
checked.
Selection group Checksum type allows selecting wished kind of checksum to be
used for main checksum. More information about Checksum types can be found at
the below.
Field Checksum contains actual value of recently calculated checksum.
Group Exclude buffer block(s) from checksum calculation - same as for Tab
Checksum calculator
Button Apply is used to confirm checksum settings from Main checksum options .
Please note, that once the button is pressed, previous checksum settings are lost.
Button Close is used to close the Checksum dialog. If you made some changes in
settings, they won't take effect until you press Apply .
(*2) These values are stored into configuration file and project file. Setting from project file
has higher precedence.
Checksum types
Byte sum (x8)
Buffer data are summed byte-by-byte irrespective of current buffer view mode (x8/x16/x1)
organization. Any carry bits exceeding 32-bits are neglected. This checksum mode is
indicated by string (x8) displayed after checksum value in main program window.
Word sum Little Endian (x16)
Buffer data are summed word-by-word irrespective of current buffer view mode organization.
Any carry bits exceeding 32-bits are neglected. This checksum mode is indicated by string
(x16 LE) displayed after checksum value in main program window. Term Little Endian means,
the buffer checksum is calculated from words read from buffer in Little Endian mode.
Word sum Big Endian (x16)
Buffer data are summed word-by-word irrespective of current buffer view mode organization.
Any carry bits exceeding 32-bits are neglected. This checksum mode is indicated by string
(x16 BE) displayed after checksum value in main program window. Term Big Endian means,
the buffer checksum is calculated from words read from buffer in Big Endian mode.
CRC-CCITT
Buffer data are summed by bytes to Word using polynomial x^16+x^12+x^5+1 (0x1021), init
value 0, and XOR out 0, reflexions in/out are off
CRC-XMODEM
Buffer data are summed by bytes to Word using polynomial x^16 + x^15 + x^2 +1 (0x8005),
init value 0
CRC-16