Function Block Operating Modes

At a Glance

The various operating modes of the function blocks depend on the following parameters:

REQ
DONE
ERROR
STATUS

Parameter Description

Execution of all EFBs of this family is asynchronous without exception towards application execution (the service can be executed over several cycles). Before starting a new operation, the DONE and ERROR bits of the previous operation must be tested, and the STATUS word must be consulted if the ERROR bit is at 1.

All of the file management EFs are configured with the following parameters:

Parameter	Type	Description
REQ	EBOOL	Starts a full operation on rising edge.
DONE	BOOL	Sets to 1 when the operation is finished. This output is reset to zero when the block is enabled by a rising edge on the REQ input.
ERROR	BOOL	Sets to 1 in case of error during execution of the operation. This output is reset to zero when the block is enabled by a rising edge on the REQ input.
STATUS	WORD	Error code. This word is only representative when an error has occurred (ERROR = 1).

The file system EFs can only be used in the MAST task. They are all executed asynchronously to the task without exception. If the EFs are called by another task, the following error code is immediately returned: SDCARD_WRONG_USER_TASK.

Illustration