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Gpio and watchdog, Gpio – Acrosser AR-R5800 User Manual

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Revision:

1.0

GPIO and Watchdog

GPIO

1. Syntax:

i32 setChDir( u8 val )

Description: Set the direction (Input/Output) of GPIO ports according to the parameter ‘val’.

Parameters: The parameter ‘val’ is an unsigned character. Each bit of *val corresponds to a
GPIO port. Bit 0 corresponds to GPIO0. Bit 1 corresponds to GPIO1. Bit 2 corresponds to
GPIO2, and so on. Setting a bit of ‘val’ as 0 configures the corresponding port as Output.
Setting a bit of ‘val’ as 1 configures the corresponding port as Input.

Return Value: If the function gets the configuration successfully, it returns 0. If any error, it
returns –1.

2. Syntax:

i32 getChDir( u8 *val )

Description: Get the direction (Input/Output) of GPIO ports and put the configuration at *val.

Parameters: The parameter ‘val’ points to an unsigned character. Each bit of *val corresponds
to a GPIO port. Bit 0 corresponds to GPIO0. Bit 1 corresponds to GPIO1. Bit 2 corresponds to
GPIO2, and so on. A ‘0’ bit at *val indicates the corresponding port is an Output port. A ‘1’ bit
at *val indicates the corresponding port is an Input port.

Return Value: If the function gets the configuration successfully, it returns 0. If any error, it
returns –1.

3. Syntax:
i32 getChLevel( u8 *val )

Description: Get the status value of GPIO ports 0~7 and put the value at *val.

Parameters: The parameter ‘val’ points to an unsigned character. If a GPIO port is configured
as an Output port, the bit at *val which corresponds to this port indicates this port is outputting
a ‘1’ or ‘0’. If a GPIO port is configured as an Input port, the corresponding bit at *val is always
‘1’.

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