EarthLCD ezLCD-405, Руководство пользователя

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e z L C D -­‐ 4 0 5 | 107
Rev.
© 2016 Earth Computers Tech. Inc.
If the file has successfully been opened, the ezLCD responds with the following sequence:
3F hex
1 dec
In case of the failure, the following sequence will be sent by the ezLCD:
3F hex
0 dec
1.7.38 SD_FILE_READ
Description: 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. Supported file systems : FAT12,
FAT16, FAT32
Code: 75 hex, 117 dec
7 6 5 4 3 2 1 0
Byte 0: Command
Byte 1: File ID
Byte 2: Number of Bytes to Read 0 (LSB)
Byte 3: Number of Bytes to Read 1
Byte 4: Number of Bytes to Read 2
Byte 5: Number of Bytes to Read 3 (MSB)
Notes: SD card has to be formatted in the supported file system. This command works only if
the file is already opened by the SD_FILE_OPEN command
See Also: SD_FILE_OPEN , SD_FILE_CLOSE , SD_FILE_CLOSE_ALL
SD_FILE_READ
FILE ID
Number of Byes to Read 0
Number of Byes to Read 2
Number of Byes to Read 1
Number of Byes to Read 3
32
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