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3 api list and descriptions – Acrosser AR-ES6003FL User Manual

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8.3 API List and Descriptions

GPIO

1. Syntax:

i32 getInChLevel( i32 channel, u8 *val )

Description: Get the value of GPIO Input and put the value at *val.

Parameters:

I.

The parameter ‘channel’ indicates the GPIO Input pins to show. Users can

use the macros GPI0, GPI1, GPI2, GPI3 to indicate the GPIO Input channel.

For example:

getInChLevel( GPI2, &val); // Indicate the GPIO Input channel 2

getInChLevel( GPI0 | GPI3, &val); // Indicate the GPIO Input

// channel 0 and channel 3

II. The parameter ‘val’ is an unsigned character pointer. The function puts the

values of the indicated GPIO channels at the memory pointed by ‘val’. The

bit 0 of *val shows the value of GPIO Input channel 0. The bit 1 of *val

shows the value of GPIO Input channel 1. Other bits show the

corresponding GPIO Input channels. Because there are only four channels,

bit 4 ~ bit 7 of *val are always zero.

Here is an example:

If GPIO Input channel 1 and channel 3 are both 1.

unsigned char ch;

getInChLevel( GPI1|GPI3, &ch );

The returned value of variable ‘ch’ is 0xa.

Return Value: If the function gets the values successfully, it returns 0. If any error,

it returns –1.

2. Syntax:

i32 setOutChLevel( i32 channel, u8 val )

Description: Set the value of GPIO Output according to the variable ‘val’.

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