Kuhnke Electronics Instruction Manual

4.5.10 Reading from a File
Function Libraries
"MMC_FileRead" lets you read data from a file. The
parameters required are the file handle of the open file, a
pointer to a buffer plus the number of bytes to be read.
This is an asynchronous Function Block. It transfers the
job to the file system and checks if it has been completed.
It needs to be run until the job has been handled
successfully.
Parameter Type Value Explanation
handle INT file handle
buff DWORD pointer to read buffer
count INT
result INT
number of bytes to be
read
0 running
< 0 error
> 0 job done
FUNCTION_BLOCK MMC_FileRead
VAR_INPUT
handle:INT;
buff:DWORD;
count:INT;
END_VAR
VAR_OUTPUT
result:INT;
END_VAR
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