EC11 Rotary Encoder with Sensor API

RE: EC11 Rotary Encoder with Sensor API

zciwor — Thu, 18 Jul 2024 14:33:17 GMT

This is what I needed!

I got the encoder working correctly using the inputs library.

Here's my new .overlay file:

/ {
    gnd_pins {
        compatible = "gpio-leds";
        qdec_gnd: qdec_gnd_pin {
            gpios = <&gpio1 14 (GPIO_ACTIVE_HIGH)>;
            label = "Rotary GND";
        };
        qdec_btn_gnd: qdec_btn_gnd_pin {
            gpios = <&gpio0 5 (GPIO_ACTIVE_HIGH)>;
            label = "Rotary btn GND";
        };
    };
    buttons: buttons {
        compatible = "gpio-keys";
        debounce-interval-ms = <50>;
        qdec_btn: btn_pin {
            gpios = <&gpio0 29 (GPIO_PULL_UP | GPIO_ACTIVE_LOW)>;
            label = "Encoder switch interrupt";
            zephyr,code = <INPUT_BTN_0>;
        };
    };
    qdec_btn {
        input = <&buttons>;
        compatible = "zephyr,input-longpress";
        input-codes = <INPUT_BTN_0>;
        short-codes = <INPUT_BTN_1>;
        long-codes = <INPUT_BTN_2>;
        long-delay-ms = <1000>;
    };
    qdec {
        compatible = "gpio-qdec";
        status = "okay";
        gpios = <&gpio1 13 (GPIO_PULL_UP | GPIO_ACTIVE_HIGH)>,
                <&gpio1 15 (GPIO_PULL_UP | GPIO_ACTIVE_HIGH)>;
        steps-per-period = <4>;
        zephyr,axis = <INPUT_REL_WHEEL>;
        sample-time-us = <2000>;
        idle-timeout-ms = <200>;
    };
};

My test main.c file:

#include <zephyr/kernel.h>
#include <zephyr/pm/pm.h>
#include <zephyr/pm/policy.h>
#include <zephyr/pm/state.h>
#include <zephyr/pm/device.h>
#include <zephyr/input/input.h>
#include <zephyr/drivers/gpio.h>

static const struct gpio_dt_spec qdec_gnd = GPIO_DT_SPEC_GET(DT_NODELABEL(qdec_gnd), gpios);
static const struct gpio_dt_spec qdec_btn_gnd = GPIO_DT_SPEC_GET(DT_NODELABEL(qdec_btn_gnd), gpios);

static void test_cb(struct input_event *evt)
{
        if (evt->code == INPUT_REL_WHEEL)
        {
                printk("z event %d\n", evt->value);
        }
        if (evt->code == INPUT_BTN_1 && evt->value == 1)
        {
                printk("short press %d\n", evt->value);
        }
        if (evt->code == INPUT_BTN_2 && evt->value == 1)
        {
                printk("long press %d\n", evt->value);
        }
}

INPUT_CALLBACK_DEFINE(NULL, test_cb);

int main(void)
{
        if (!gpio_is_ready_dt(&qdec_gnd) || !gpio_is_ready_dt(&qdec_btn_gnd))
        {
                printk("Device not ready\n");
        }

        gpio_pin_configure_dt(&qdec_gnd, GPIO_OUTPUT_LOW);
        gpio_pin_configure_dt(&qdec_btn_gnd, GPIO_OUTPUT_LOW);

        while (1)
        {
                k_sleep(K_FOREVER);
        }
}

And prj.conf file:

# Config encoder
CONFIG_INPUT=y
CONFIG_INPUT_GPIO_QDEC=y

For anyone wondering about the ground pins, here's how I have my encoder connected:

Full sample project also included.

devzone.nordicsemi.com/.../xiao_2D00_pp.zip

RE: EC11 Rotary Encoder with Sensor API

Øyvind — Thu, 18 Jul 2024 09:22:32 GMT

I'm afraid that there is not much help from my side with Zephyr drivers, as we do not have much rotary encoders in our products.

Looking at zephyr/dts/bindings/input/gpio-qdec.yaml please make sure that you have configured the rotary encoder with the following

  qdec {
          compatible = "gpio-qdec";
          gpios = <&gpio0 14 (GPIO_PULL_UP | GPIO_ACTIVE_HIGH)>,
                  <&gpio0 13 (GPIO_PULL_UP | GPIO_ACTIVE_HIGH)>;
          steps-per-period = <4>;
          zephyr,axis = <INPUT_REL_WHEEL>;
          sample-time-us = <2000>;
          idle-timeout-ms = <200>;
  };

This is used in zephyr/samples/subsys/display/lvgl/boards/native_posix.overlay

Does this help with your rotary encoder output? Next step would be to debug using e.g. logic analyzer to ensure the signals are correct

Looking at the zephyr/samples/subsys/display/lvgl/src/main.c the following snippet should provide some help, and perhaps help with debugging i.e. setting break points

#ifdef CONFIG_LV_Z_ENCODER_INPUT
	lv_obj_t *arc;
	lv_group_t *arc_group;

	arc = lv_arc_create(lv_scr_act());
	lv_obj_align(arc, LV_ALIGN_CENTER, 0, -15);
	lv_obj_set_size(arc, 150, 150);

	arc_group = lv_group_create();
	lv_group_add_obj(arc_group, arc);
	lv_indev_set_group(lvgl_input_get_indev(lvgl_encoder), arc_group);
#endif /* CONFIG_LV_Z_ENCODER_INPUT */

zephyr/modules/lvgl/input/lvgl_encoder_input.c

And I assume you have been looking at the QDEC sameple (zephyr/samples/sensor/qdec/src/main.c)

RE: EC11 Rotary Encoder with Sensor API

zciwor — Tue, 16 Jul 2024 14:18:34 GMT

No response yet on the Zephyr channel.

RE: EC11 Rotary Encoder with Sensor API

Øyvind — Tue, 16 Jul 2024 06:13:21 GMT

Hello,

No, I'm afraid I've had no luck so far.

Did you have any luck in the Zephyr channel?

-Øyvind

RE: EC11 Rotary Encoder with Sensor API

zciwor — Mon, 15 Jul 2024 20:05:46 GMT

Hi Øyvind have you had any luck identifying the issue with your encoder? I still have not been able to find an answer.

RE: EC11 Rotary Encoder with Sensor API

zciwor — Thu, 11 Jul 2024 12:33:20 GMT

Thanks for your quick response! I am on nRF Connect version 2.6.1. I can try the latest release and see if there is any difference.

Unfortunately I do not have access to an oscilloscope or logic meter at this time. I will try cross-posting in the Zephyr Discord to see if anyone has any ideas and report back.

RE: EC11 Rotary Encoder with Sensor API

Øyvind — Thu, 11 Jul 2024 10:11:31 GMT

Hello,

What version of the nRF Connect SDK are you using? I've tested with a similar rotary encoder here but with no luck. Saw similar output and put aside. Let's look into this together. Your overlay looks correct. What about the signals on the encoder, have you tried looking at these with a logic analyzer or oscilloscope? The issue is most like in the SDK.

The Zephyr Community on Discord might be the best chance of figuring out this issue. There are relevant discussions there e.g. https://github.com/zephyrproject-rtos/zephyr/issues/73529

Kind regards,
Øyvind