EarthLCD ezLCD-405, Руководство пользователя

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e z L C D -­‐ 4 0 5 | 95
Rev.
© 2016 Earth Computers Tech. Inc.
1.7.33 SD_FILE_CREATE
Description: Creates a new SD Flash file and opens it for writing. File Position Index is set to 0.
Supported file systems : FAT12, FAT16, FAT32
Code: 76 hex, 118 dec
7 6 5 4 3 2 1 0
Byte 0: Command
Byte 1: File ID
Byte 2: First Character of the file path
Byte 3: Second Character of the file path
Notes: SD card has to be formatted in the supported file system.
See Also: SD_FILE_OPEN , SD_FILE_CLOSE , SD_FILE_CLOSE_ALL
About the File ID:
File ID identifies the file after it has been opened. Since maximum 2 files may be concurrently
opened, the File ID should be: 1 or 2. Values higher than 2 are interpreted as 2 and 0 is
interpreted as 1.
About the File Path:
·∙ 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.
Byte n: Last Character
Byte n+1: NULL
SD_FILE_CREATE
File ID
ASCII
ASCII
Pa
th
to
th
e
fil
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on
S
D
(N
U
LL
-­‐te
rm
in
ate
d
st
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g)
ASCII
0