Dataman 40PRO, Руководство пользователя

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Size Size of chosen checksum result, which will be written into the
buffer. A size of inserted checksum may be Byte (8-bit), Word (16-
bit) or DWORD (32-bit). If size is smaller then selected checksum
size, only lower byte(s) of checksum value will be written into the
buffer.
Note: If Word size was selected, a low byte of checksum value will
be written on address specified in box Insert address and a high
byte will be written on address incremented by one. Similarly it is
for DWORD.
Calculate button - click on the button Calculate starts calculating checksums for selected
block in buffer. No writes into the buffer are executed.
Calculate & insert button - click on the button Calculate & insert starts calculating
checksums for selected block in the buffer and writes the chosen checksum into the buffer
on address specified by Insert address. This function is available for Byte, Word, CRC-
CCITT and CRC-XMODEM checksums.
Close button - closes dialog Checksum.
(*1) These values aren't saved into project; they are initialized to defaults with each new device
selection.
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 bellow.
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.