How to use gpio interrupt?

[ly0]

I haven't seen any API could do this.

[donnib]

@ly0 have you found any info on this ? I am looking for the same info.

[ly0]

@donnib refered to http://g-lab.ca/esp8266ex-gpio-registers/, maybe we need to handle the related registers directly. search 'INT' for more info on that page. But I haven't tried.

[espressif]

gpio driver has been upload, you can have a test.

[donnib]

@espressif which driver are you reffering to ? 0.9.4 has GPIO interrupt supported ? If so any documentation about that ?

[ly0]

@donnib see this https://github.com/espressif/esp_iot_rtos_sdk/tree/master/examples/dirver_lib

[Karang]

In the exemple you talked about a gpio_intr_ack function (https://github.com/espressif/esp_iot_rtos_sdk/blob/master/examples/driver_lib/driver/gpio.c#L101). But I can't find it anywhere. Even if I add the signature : void gpio_intr_ack(uint32 mask); the linker can't find it.

EDIT: I managed to compile by providing the address to the linker (PROVIDE ( gpio_intr_ack = 0x40004dcc );) But now I'm getting this exception when I trigger my interrupt :

Fatal exception (20): (EXCCAUSE_INSTR_PROHIBITED)
epc1=0x00000004
epc2=0x00000000
epc3=0x4024306f
epcvaddr=0x00000004
depc=0x00000000

Here is my code :

LOCAL void (*callbacks[16])(void);
LOCAL void interruptHandler(int gpio_mask) {
    for (int i=0 ; i<16 ; i++) {
        if ((0x1<<i) & gpio_mask) {
            if (callbacks[i] != NULL) {
                (*callbacks[i])();
            }
        }
    }
    gpio_intr_ack(gpio_mask);
}

And this is how i register the handler :

for (int i=0 ; i<16 ; i++) {
    callbacks[i] = NULL;
}
_xt_isr_attach(ETS_GPIO_INUM, (_xt_isr)interruptHandler);
_xt_isr_unmask(1<<ETS_GPIO_INUM);

EDIT2: It seems that the interrupt is given no arguments (gpio_mask is always 16, whatever the pin are). I tried to use gpio_intr_pending(); but it always return 0 and throw a 29 (EXCCAUSE_STORE_PROHIBITED) exception. It also seems that the interrupt is triggered a lot before crashing, shouldn't it be triggered once ?

EDIT3: I tried to use _xt_clear_ints(uint32 mask); and _xt_read_ints(); but I have the same issue, with _xt_read_ints(); returning a lot of 20 and some 84.

[Karang]

Any idea ? This issue seems to be linked with the pwm one.

Edit: an answer has been found by hreintke on esp8266.com : http://www.esp8266.com/viewtopic.php?f=8&t=241&p=7246#p7246

[HomeACcessoryKid]

Now, 2 years later, is there an answer to this?
For now I cannot see any clear instructions in the SDK itself and the driver code seems incomplete.
For example, gpio.c contains the function gpio_config() but there is no prototype in gpio.h
The example given on espressif site depends on this function...

Is there a conclusive example how to do this??

[HomeACcessoryKid]

I propose to add this to the official distribution: it is backward compatible and it means people can have a 'one-stop-shop-experience' by just reading the gpio.h file.

//example based on ESP8266_RTOS_SDK version 1.5.0
#include "esp_common.h"
#include "gpio.h"

#define GPIO_INPUT(gpio_bits)       ((gpio_input_get()&gpio_bits)?1:0)
#define GPIO_INTERRUPT_ENABLE   _xt_isr_unmask(1 << ETS_GPIO_INUM)
void gpio_config(GPIO_ConfigTypeDef *pGPIOConfig);

/******************************************************************************
 * FunctionName : gpio_intr_handler - generic handling of GPIO interrupts
*******************************************************************************/
void (*gpio_intr_callbacks[16])(void);
void gpio_intr_handler() {
    int i;
    uint32 gpio_mask = _xt_read_ints();
    uint32_t gpio_status = GPIO_REG_READ(GPIO_STATUS_ADDRESS);
    os_printf("interrupt@%dus: mask=0x%02x, status=0x%02x\n",system_get_time(),gpio_mask,gpio_status);
    for (i=0 ; i<16 ; i++)
        if ( (0x1<<i) & gpio_status & gpio_intr_callbacks[i]!= NULL )
            (*gpio_intr_callbacks[i])();   
    GPIO_REG_WRITE(GPIO_STATUS_W1TC_ADDRESS, gpio_status );     //clear interrupt status
}

//****** THE ITEMS ABOVE SHOULD BE ADDED TO THE GPIO driver files ************//

/******************************************************************************
 * FunctionName : Pin0 specific interrupt handler
*******************************************************************************/
LOCAL void callback0() {
    static uint32  oldtime;
//  os_printf("oldtime: %d\n",oldtime);
    if ( (oldtime+200)<(oldtime=(system_get_time()/1000) ) ) {  //200ms debounce guard
        GPIO_OUTPUT(GPIO_Pin_2,GPIO_INPUT(GPIO_Pin_2)^1);       //toggle
        os_printf("Pin2-toggle\n");
    }
//  os_printf("newtime: %d\n",oldtime);
}

/******************************************************************************
 * FunctionName : user_init
*******************************************************************************/
void user_init(void)
{   
    GPIO_ConfigTypeDef gpio0_in_cfg;                            //Define GPIO Init Structures
    GPIO_ConfigTypeDef gpio2_in_cfg;

    gpio0_in_cfg.GPIO_IntrType = GPIO_PIN_INTR_NEGEDGE;         //Falling edge trigger
    gpio0_in_cfg.GPIO_Mode     = GPIO_Mode_Input;               //Input mode
    gpio0_in_cfg.GPIO_Pin      = GPIO_Pin_0;                    //Enable GPIO
    gpio_config(&gpio0_in_cfg);                                 //Initialization function
    gpio_intr_handler_register(gpio_intr_handler,NULL);         //Register the interrupt function
    GPIO_INTERRUPT_ENABLE;

    gpio_intr_callbacks[0]=callback0;                           //define the Pin0 callback

    gpio2_in_cfg.GPIO_IntrType = GPIO_PIN_INTR_DISABLE;         //no interrupt
    gpio2_in_cfg.GPIO_Mode     = GPIO_Mode_Output;              //Output mode
    gpio2_in_cfg.GPIO_Pullup   = GPIO_PullUp_EN;                //improves transitions
    gpio2_in_cfg.GPIO_Pin      = GPIO_Pin_2;                    //Enable GPIO
    gpio_config(&gpio2_in_cfg);                                 //Initialization function
}

/***********************************************************************************
 * FunctionName : user_rf_cal_sector_set forced upon us by espressif since RTOS1.4.2
***********************************************************************************/
uint32 user_rf_cal_sector_set(void) {
    extern char flashchip;
    SpiFlashChip *flash = (SpiFlashChip*)(&flashchip + 4);
    //sec_num = chip_size / flash->sector_size; but sector size is 4096 = 2^12
    uint32_t sec_num = flash->chip_size >> 12;
    return sec_num - 5;
}