EarthLCD ezLCD-405, Руководство пользователя

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e z L C D -­‐ 4 0 5 | 45
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© 2016 Earth Computers Tech. Inc.
SD_FILE_CLOSE_ALL
Closes all opened SD Flash files and re-­‐enables the touch screen.
SD_FILE_GET_SIZE
Gets the size (in bytes) of the opened SD Flash file.
SD_FILE_READ
Reads the specified number of bytes from the opened SD Flash file, starting from File Position
Index. File Position Index is incremented by the number of the bytes read, however it will not
exceed file_size-­‐ 1.
SD_FILE_WRITE
Writes the specified number of bytes to the opened SD Flash file, starting from File Position
Index. File Position Index is incremented by the number of the bytes written.
SD_FILE_SEEK
Moves the File Position Index of the opened SD Flash file by the specified number of bytes,
from the position specified by the parameter.
SD_FILE_REWIND
Moves the File Position Index to the beginning of the opened SD Flash file.
SD_FILE_TELL
Gets the File Position Index of the opened SD Flash file.
SD_FILE_DELETE
Deletes the SD file.
SD_FOLDER_CREATE
Creates a new folder (directory) on the SD.
SD_FOLDER_DELETE
Deletes an empty folder (directory) on the SD.
SD_SPACE_INFO
Gets the information about the space usage (in bytes) of the formatted SD Card.
SD_PUT_ICON
Reads and displays the bitmap file.
About the File Position Index
The File Position Index specifies the Read/Write position offset (in bytes) from the beginning of
the file. Upon opening of the file, the File Position Index is set to 0. The File Position Index is
incremented by the subsequent read or write operations on the opened file.
About the SD File Path used in the commands:
·∙ File Path specifies the full path to the file on SD including directory, filename and extension
·∙ Directories should be separated by: / ( not by: \ like in Windows and DOS).
·∙ File Path is not case-­‐sensitive. The drive and root directory do not have to be indicated, for
example, both: A:/Cat/Jumped/Over.txt and cat/jumped/over.TXT specify the same file.
·∙ Long file names are supported, however the File Path (directory + filename + extension +
NULL) may not exceed 64 bytes.