esp8266_easygpio

An easy way of setting up esp8266 GPIO pins.

I grew tired of juggling gpio pin numbers, gpio names and gpio functions. So i created this little helper library.

To setup a pin as a GPIO input you can now just do this:

#include "easygpio/easygpio.h"
...
bool easygpio_pinMode(0, EASYGPIO_NOPULL, EASYGPIO_INPUT);

Same thing with outputs:

bool easygpio_pinMode(1, EASYGPIO_NOPULL, EASYGPIO_OUTPUT);

pullStatus does not apply to output pins.

You might still need the gpio_name and func. No problem:

bool easygpio_getGPIONameFunc(uint8_t gpio_pin, uint32_t *gpio_name, uint8_t *gpio_func)

You can even setup an interrupt handler:

bool easygpio_attachInterrupt(uint8_t gpio_pin, EasyGPIO_PullStatus pullStatus, void (*interruptHandler)(void* arg), void *interruptArg)

You can use the methods and macros defined in gpio.h (from the sdk) to access the 'standard' gpio pins (not GPIO16).

#include "gpio.h"
...
GPIO_OUTPUT_SET(gpio_no, bit_value) // GPIO_OUTPUT_SET(0,1) sets gpio0 to high
GPIO_DIS_OUTPUT(gpio_no) // GPIO_DIS_OUTPUT(2) turns off output on gpio2
GPIO_INPUT_GET(gpio_no) // GPIO_INPUT_GET(12) returns the input value of gpio12

To access all of the pins in an uniform way you can use

uint8_t easygpio_inputGet(uint8_t gpio_pin);
void easygpio_outputSet(uint8_t gpio_pin, uint8_t value);

However, you should not rely on that these methods will change input/output status of a pin (like the gpio.h macros does).

e.g. if you call easygpio_outputSet on an input pin, the pin may or may not remain an input. This is because of performance and uniformity reasons. easygpio_outputSet(16,1) will never flip gpio16 to an output, and we can't have access methods with different semantics depending on pin number).

So if you need to change the input/output mode of a pin on the fly, you can use easygpio_outputDisable() or easygpio_outputEnable().

###Available pins

All the GPIOs mentioned in easgle_soc.h are supported, but maybe we should not mess with the internal SPI pins for GPIO.

Usage

The project has been designed for easy reuse, just create a folder with these files in it (git subtree works great for that purpose). Then point your MODULES variable (or whatever subdirectory construct you use) in the Makefile to that folder . If you find yourself manually copying these individial .c and .h files - you're doing it wrong.

See an example on how this library can be used here, here, here, here - bha.. practically all of my esp projects uses it.

Todo

• Find the correct READ_PERI_REG() address for easygpio_inputGet(), now it's simply using GPIO_INPUT_GET()

Required:

esp-open-sdk-v0.9.5 or higher.

I've successfully tested this with sdk v1.5.2 and v0.9.5 (linux & mac).