Week 10, 11, 12
Output Device, Networking, and App Programming
Preface
I went on a very fun and sick and cool trip to China over the last few weeks. I travelled to Shenzhen and Hong Kong.
Some key takeaways from the trip, some about tech, some not (I'm doing a full blog post writeup about what I learned:
- Speed - China is faster to get things, get things made, meet people, make deals, and learn.
- Community - there is a super strong maker, hacker, manufacturing, electronics community there that is second to none. They are really fast to offer opportunities it seems - I have a couple offers to work/do research there if I want to.
- Culture - there's a massive language barrier. Many companies there have 0 people who speak english. They have all kinds of amazing tech that you would never find if you Google'd for it. The IP is willy-nilly - they care way less about copyright and are less afraid of IP issues, less afraid of people stealing their ideas, etc., they'll show off everything
- Life - everything is way cheaper. Like everything is 1/3 to 1/10 the price there if you convert to USD. It's super safe. I didn't see a lot of party life, but people love to get dinner and drinks and talk late into the night. The conversations are more interesting than in most parts of the world - kindof more like an MIT dinner party than most of the rest of the US.
- Areas - different areas are completely different. Hong Kong is way chiller and much more people speak english. Shenzhen is 10,000 miles a minute and a lot more "foreign" feeling
All that said, I am weeks behind, so I am doing 1 project that covers all 3 weeks I missed, and that project is...
Intro - the Smart Ring
I have slightly changed tracked for my final project as I already build the SVAD. I want to now make "the alternative cyborg". That is a cyborg tech stack that is completely different than the mainstream, expected tech stack that most cookie-cutter cyborgs don - it consists of a smart ring and a uPhone/ShareableWearable. This week I make the dumb v0.1 version of the smart ring.
The Plan
Let's make a smart ring. I will 3D print the ring, then glue the componenets to the outside. For output devices I will put LEDs and a vibration motor on the ring. For networking I will connect the ring wireless to my phone and control the lights. For applications programming I will make an Android app that connects to the ring and controls the lights.
Mechanical - Smart Ring
I made a circle in Fusion. Then I made another circle and offset it from the first. Then I extruded the ring in between the two circles. Then I filleted the edges. Now I have a smart ring. This first version, with all modular components, will be big, so I
That pre-fillet ring. In future, design your own board so you don't have an 18mm long ring to fit the XIAO and stuff.
Output Devices - LEDs and Vibration Motor
I designed a simple board with XIAO ESP32S3, 3 LEDs, a button, and some breakout pins. I put test points all over and designed the board to be cut into 3 pieces that could be attached to the board. Alas, the bed was uneven and the XIAO half of the board failed, but I did not have time, so I just used the LED part of the board and soldered the rest.
Put that all together
I put it all together into a very rough prototype smart ring. The battery is a VARTA CP9440 which is one of the smallest 3.7V batteries in the world. The LEDs are on their own circuit board (that was cut out from the main board) on the top. The vibration motor is glued onto the side and free soldered to the LED board and the MCU (with a current limited resistor in parallel).
Networking
Then I made the Bluetoothy goodness. I should have just used Arduino but I am a respectable person so I don't want to use Arduino bluetooth. So I spent 2 hours setting up espidf again on my new computer and using this example to make a GATT characteristic that would turn on and off the LEDs: https://github.com/espressif/esp-idf/blob/master/examples/bluetooth/bluedroid/ble/gatt_server/tutorial/Gatt_Server_Example_Walkthrough.md
Here's my code after modification to detect subscription, accept write events on the characteristic, and respond to those events by changing LED states:
/*
* SPDX-FileCopyrightText: 2021-2023 Espressif Systems (Shanghai) CO LTD
*
* SPDX-License-Identifier: Unlicense OR CC0-1.0
*/
/****************************************************************************
*
* This demo showcases BLE GATT server. It can send adv data, be connected by client.
* Run the gatt_client demo, the client demo will automatically connect to the gatt_server demo.
* Client demo will enable gatt_server's notify after connection. The two devices will then exchange
* data.
*
****************************************************************************/
#include
#include
#include
#include
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/event_groups.h"
#include "esp_system.h"
#include "esp_log.h"
#include "nvs_flash.h"
#include "esp_bt.h"
#include "esp_gap_ble_api.h"
#include "esp_gatts_api.h"
#include "esp_bt_defs.h"
#include "esp_bt_main.h"
#include "esp_gatt_common_api.h"
//gpio
#include "driver/gpio.h"
#include "sdkconfig.h"
#define GATTS_TAG "OSSR_Smart_Ring_TOSG"
//LEDs
#define RED_LED 7
#define ORANGE_LED 8
#define GREEN_LED 9
#define VIBRATE_GPIO 5
void control_led(uint8_t led_value) {
ESP_LOGI(GATTS_TAG, "RUNNING CTONROL LED WITH:\n");
ESP_LOGI(GATTS_TAG, "%d\n", led_value);
switch(led_value) {
case 0:
gpio_set_level(RED_LED, 1); // Turn RED_LED on
break;
case 1:
gpio_set_level(RED_LED, 0); // Turn RED_LED off
break;
case 2:
gpio_set_level(ORANGE_LED, 1); // Turn ORANGE_LED on
break;
case 3:
gpio_set_level(ORANGE_LED, 0); // Turn ORANGE_LED off
break;
case 4:
gpio_set_level(GREEN_LED, 1); // Turn GREEN_LED on
break;
case 5:
gpio_set_level(GREEN_LED, 0); // Turn GREEN_LED off
break;
case 6:
gpio_set_level(VIBRATE_GPIO, 1); // vibrate briefly
vTaskDelay(250 / portTICK_PERIOD_MS);
gpio_set_level(VIBRATE_GPIO, 0); // stop vibrate
break;
default:
// Handle unknown values
break;
}
}
///Declare the static function
static void gatts_profile_a_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_if, esp_ble_gatts_cb_param_t *param);
static void gatts_profile_b_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_if, esp_ble_gatts_cb_param_t *param);
#define GATTS_SERVICE_UUID_TEST_A 0x00FF
#define GATTS_CHAR_UUID_TEST_A 0xFF01
#define GATTS_DESCR_UUID_TEST_A 0x3333
#define GATTS_NUM_HANDLE_TEST_A 4
#define GATTS_SERVICE_UUID_TEST_B 0x00EE
#define GATTS_CHAR_UUID_TEST_B 0xEE01
#define GATTS_DESCR_UUID_TEST_B 0x2222
#define GATTS_NUM_HANDLE_TEST_B 4
#define TEST_DEVICE_NAME "OSSR_cayden"
#define TEST_MANUFACTURER_DATA_LEN 17
#define GATTS_DEMO_CHAR_VAL_LEN_MAX 0x40
#define PREPARE_BUF_MAX_SIZE 1024
static uint8_t char1_str[] = {0x11,0x22,0x33};
static esp_gatt_char_prop_t a_property = 0;
static esp_gatt_char_prop_t b_property = 0;
static esp_attr_value_t gatts_demo_char1_val =
{
.attr_max_len = GATTS_DEMO_CHAR_VAL_LEN_MAX,
.attr_len = sizeof(char1_str),
.attr_value = char1_str,
};
static uint8_t adv_config_done = 0;
#define adv_config_flag (1 << 0)
#define scan_rsp_config_flag (1 << 1)
#ifdef CONFIG_SET_RAW_ADV_DATA
static uint8_t raw_adv_data[] = {
0x02, 0x01, 0x06, // Length 2, Data Type 1 (Flags), Data 1 (LE General Discoverable Mode, BR/EDR Not Supported)
0x02, 0x0a, 0xeb, // Length 2, Data Type 10 (TX power leve), Data 2 (-21)
0x03, 0x03, 0xab, 0xcd, // Length 3, Data Type 3 (Complete 16-bit Service UUIDs), Data 3 (UUID)
};
static uint8_t raw_scan_rsp_data[] = { // Length 15, Data Type 9 (Complete Local Name), Data 1 (ESP_GATTS_DEMO)
0x0f, 0x09, 0x45, 0x53, 0x50, 0x5f, 0x47, 0x41, 0x54, 0x54, 0x53, 0x5f, 0x44,
0x45, 0x4d, 0x4f
};
#else
static uint8_t adv_service_uuid128[32] = {
/* LSB <--------------------------------------------------------------------------------> MSB */
//first uuid, 16bit, [12],[13] is the value
0xfb, 0x34, 0x9b, 0x5f, 0x80, 0x00, 0x00, 0x80, 0x00, 0x10, 0x00, 0x00, 0xEE, 0x00, 0x00, 0x00,
//second uuid, 32bit, [12], [13], [14], [15] is the value
0xfb, 0x34, 0x9b, 0x5f, 0x80, 0x00, 0x00, 0x80, 0x00, 0x10, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00,
};
// The length of adv data must be less than 31 bytes
//static uint8_t test_manufacturer[TEST_MANUFACTURER_DATA_LEN] = {0x12, 0x23, 0x45, 0x56};
//adv data
static esp_ble_adv_data_t adv_data = {
.set_scan_rsp = false,
.include_name = true,
.include_txpower = false,
.min_interval = 0x0006, //slave connection min interval, Time = min_interval * 1.25 msec
.max_interval = 0x0010, //slave connection max interval, Time = max_interval * 1.25 msec
.appearance = 0x00,
.manufacturer_len = 0, //TEST_MANUFACTURER_DATA_LEN,
.p_manufacturer_data = NULL, //&test_manufacturer[0],
.service_data_len = 0,
.p_service_data = NULL,
.service_uuid_len = sizeof(adv_service_uuid128),
.p_service_uuid = adv_service_uuid128,
.flag = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT),
};
// scan response data
static esp_ble_adv_data_t scan_rsp_data = {
.set_scan_rsp = true,
.include_name = true,
.include_txpower = true,
//.min_interval = 0x0006,
//.max_interval = 0x0010,
.appearance = 0x00,
.manufacturer_len = 0, //TEST_MANUFACTURER_DATA_LEN,
.p_manufacturer_data = NULL, //&test_manufacturer[0],
.service_data_len = 0,
.p_service_data = NULL,
.service_uuid_len = sizeof(adv_service_uuid128),
.p_service_uuid = adv_service_uuid128,
.flag = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT),
};
#endif /* CONFIG_SET_RAW_ADV_DATA */
static esp_ble_adv_params_t adv_params = {
.adv_int_min = 0x20,
.adv_int_max = 0x40,
.adv_type = ADV_TYPE_IND,
.own_addr_type = BLE_ADDR_TYPE_PUBLIC,
//.peer_addr =
//.peer_addr_type =
.channel_map = ADV_CHNL_ALL,
.adv_filter_policy = ADV_FILTER_ALLOW_SCAN_ANY_CON_ANY,
};
#define PROFILE_NUM 2
#define PROFILE_A_APP_ID 0
#define PROFILE_B_APP_ID 1
struct gatts_profile_inst {
esp_gatts_cb_t gatts_cb;
uint16_t gatts_if;
uint16_t app_id;
uint16_t conn_id;
uint16_t service_handle;
esp_gatt_srvc_id_t service_id;
uint16_t char_handle;
esp_bt_uuid_t char_uuid;
esp_gatt_perm_t perm;
esp_gatt_char_prop_t property;
uint16_t descr_handle;
esp_bt_uuid_t descr_uuid;
};
/* One gatt-based profile one app_id and one gatts_if, this array will store the gatts_if returned by ESP_GATTS_REG_EVT */
static struct gatts_profile_inst gl_profile_tab[PROFILE_NUM] = {
[PROFILE_A_APP_ID] = {
.gatts_cb = gatts_profile_a_event_handler,
.gatts_if = ESP_GATT_IF_NONE, /* Not get the gatt_if, so initial is ESP_GATT_IF_NONE */
},
[PROFILE_B_APP_ID] = {
.gatts_cb = gatts_profile_b_event_handler, /* This demo does not implement, similar as profile A */
.gatts_if = ESP_GATT_IF_NONE, /* Not get the gatt_if, so initial is ESP_GATT_IF_NONE */
},
};
typedef struct {
uint8_t *prepare_buf;
int prepare_len;
} prepare_type_env_t;
static prepare_type_env_t a_prepare_write_env;
static prepare_type_env_t b_prepare_write_env;
void example_write_event_env(esp_gatt_if_t gatts_if, prepare_type_env_t *prepare_write_env, esp_ble_gatts_cb_param_t *param);
void example_exec_write_event_env(prepare_type_env_t *prepare_write_env, esp_ble_gatts_cb_param_t *param);
static void gap_event_handler(esp_gap_ble_cb_event_t event, esp_ble_gap_cb_param_t *param)
{
switch (event) {
#ifdef CONFIG_SET_RAW_ADV_DATA
case ESP_GAP_BLE_ADV_DATA_RAW_SET_COMPLETE_EVT:
adv_config_done &= (~adv_config_flag);
if (adv_config_done==0){
esp_ble_gap_start_advertising(&adv_params);
}
break;
case ESP_GAP_BLE_SCAN_RSP_DATA_RAW_SET_COMPLETE_EVT:
adv_config_done &= (~scan_rsp_config_flag);
if (adv_config_done==0){
esp_ble_gap_start_advertising(&adv_params);
}
break;
#else
case ESP_GAP_BLE_ADV_DATA_SET_COMPLETE_EVT:
adv_config_done &= (~adv_config_flag);
if (adv_config_done == 0){
esp_ble_gap_start_advertising(&adv_params);
}
break;
case ESP_GAP_BLE_SCAN_RSP_DATA_SET_COMPLETE_EVT:
adv_config_done &= (~scan_rsp_config_flag);
if (adv_config_done == 0){
esp_ble_gap_start_advertising(&adv_params);
}
break;
#endif
case ESP_GAP_BLE_ADV_START_COMPLETE_EVT:
//advertising start complete event to indicate advertising start successfully or failed
if (param->adv_start_cmpl.status != ESP_BT_STATUS_SUCCESS) {
ESP_LOGE(GATTS_TAG, "Advertising start failed\n");
}
break;
case ESP_GAP_BLE_ADV_STOP_COMPLETE_EVT:
if (param->adv_stop_cmpl.status != ESP_BT_STATUS_SUCCESS) {
ESP_LOGE(GATTS_TAG, "Advertising stop failed\n");
} else {
ESP_LOGI(GATTS_TAG, "Stop adv successfully\n");
}
break;
case ESP_GAP_BLE_UPDATE_CONN_PARAMS_EVT:
ESP_LOGI(GATTS_TAG, "update connection params status = %d, min_int = %d, max_int = %d,conn_int = %d,latency = %d, timeout = %d",
param->update_conn_params.status,
param->update_conn_params.min_int,
param->update_conn_params.max_int,
param->update_conn_params.conn_int,
param->update_conn_params.latency,
param->update_conn_params.timeout);
break;
default:
break;
}
}
void example_write_event_env(esp_gatt_if_t gatts_if, prepare_type_env_t *prepare_write_env, esp_ble_gatts_cb_param_t *param){
esp_gatt_status_t status = ESP_GATT_OK;
if (param->write.need_rsp){
if (param->write.is_prep){
if (prepare_write_env->prepare_buf == NULL) {
prepare_write_env->prepare_buf = (uint8_t *)malloc(PREPARE_BUF_MAX_SIZE*sizeof(uint8_t));
prepare_write_env->prepare_len = 0;
if (prepare_write_env->prepare_buf == NULL) {
ESP_LOGE(GATTS_TAG, "Gatt_server prep no mem\n");
status = ESP_GATT_NO_RESOURCES;
}
} else {
if(param->write.offset > PREPARE_BUF_MAX_SIZE) {
status = ESP_GATT_INVALID_OFFSET;
} else if ((param->write.offset + param->write.len) > PREPARE_BUF_MAX_SIZE) {
status = ESP_GATT_INVALID_ATTR_LEN;
}
}
esp_gatt_rsp_t *gatt_rsp = (esp_gatt_rsp_t *)malloc(sizeof(esp_gatt_rsp_t));
gatt_rsp->attr_value.len = param->write.len;
gatt_rsp->attr_value.handle = param->write.handle;
gatt_rsp->attr_value.offset = param->write.offset;
gatt_rsp->attr_value.auth_req = ESP_GATT_AUTH_REQ_NONE;
memcpy(gatt_rsp->attr_value.value, param->write.value, param->write.len);
esp_err_t response_err = esp_ble_gatts_send_response(gatts_if, param->write.conn_id, param->write.trans_id, status, gatt_rsp);
if (response_err != ESP_OK){
ESP_LOGE(GATTS_TAG, "Send response error\n");
}
free(gatt_rsp);
if (status != ESP_GATT_OK){
return;
}
memcpy(prepare_write_env->prepare_buf + param->write.offset,
param->write.value,
param->write.len);
prepare_write_env->prepare_len += param->write.len;
}else{
esp_ble_gatts_send_response(gatts_if, param->write.conn_id, param->write.trans_id, status, NULL);
}
}
}
void example_exec_write_event_env(prepare_type_env_t *prepare_write_env, esp_ble_gatts_cb_param_t *param){
if (param->exec_write.exec_write_flag == ESP_GATT_PREP_WRITE_EXEC){
esp_log_buffer_hex(GATTS_TAG, prepare_write_env->prepare_buf, prepare_write_env->prepare_len);
}else{
ESP_LOGI(GATTS_TAG,"ESP_GATT_PREP_WRITE_CANCEL");
}
if (prepare_write_env->prepare_buf) {
free(prepare_write_env->prepare_buf);
prepare_write_env->prepare_buf = NULL;
}
prepare_write_env->prepare_len = 0;
}
static void gatts_profile_a_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_if, esp_ble_gatts_cb_param_t *param) {
switch (event) {
case ESP_GATTS_REG_EVT:
ESP_LOGI(GATTS_TAG, "REGISTER_APP_EVT, status %d, app_id %d\n", param->reg.status, param->reg.app_id);
gl_profile_tab[PROFILE_A_APP_ID].service_id.is_primary = true;
gl_profile_tab[PROFILE_A_APP_ID].service_id.id.inst_id = 0x00;
gl_profile_tab[PROFILE_A_APP_ID].service_id.id.uuid.len = ESP_UUID_LEN_16;
gl_profile_tab[PROFILE_A_APP_ID].service_id.id.uuid.uuid.uuid16 = GATTS_SERVICE_UUID_TEST_A;
esp_err_t set_dev_name_ret = esp_ble_gap_set_device_name(TEST_DEVICE_NAME);
if (set_dev_name_ret){
ESP_LOGE(GATTS_TAG, "set device name failed, error code = %x", set_dev_name_ret);
}
#ifdef CONFIG_SET_RAW_ADV_DATA
esp_err_t raw_adv_ret = esp_ble_gap_config_adv_data_raw(raw_adv_data, sizeof(raw_adv_data));
if (raw_adv_ret){
ESP_LOGE(GATTS_TAG, "config raw adv data failed, error code = %x ", raw_adv_ret);
}
adv_config_done |= adv_config_flag;
esp_err_t raw_scan_ret = esp_ble_gap_config_scan_rsp_data_raw(raw_scan_rsp_data, sizeof(raw_scan_rsp_data));
if (raw_scan_ret){
ESP_LOGE(GATTS_TAG, "config raw scan rsp data failed, error code = %x", raw_scan_ret);
}
adv_config_done |= scan_rsp_config_flag;
#else
//config adv data
esp_err_t ret = esp_ble_gap_config_adv_data(&adv_data);
if (ret){
ESP_LOGE(GATTS_TAG, "config adv data failed, error code = %x", ret);
}
adv_config_done |= adv_config_flag;
//config scan response data
ret = esp_ble_gap_config_adv_data(&scan_rsp_data);
if (ret){
ESP_LOGE(GATTS_TAG, "config scan response data failed, error code = %x", ret);
}
adv_config_done |= scan_rsp_config_flag;
#endif
esp_ble_gatts_create_service(gatts_if, &gl_profile_tab[PROFILE_A_APP_ID].service_id, GATTS_NUM_HANDLE_TEST_A);
break;
case ESP_GATTS_READ_EVT: {
ESP_LOGI(GATTS_TAG, "GATT_READ_EVT, conn_id %d, trans_id %" PRIu32 ", handle %d\n", param->read.conn_id, param->read.trans_id, param->read.handle);
esp_gatt_rsp_t rsp;
memset(&rsp, 0, sizeof(esp_gatt_rsp_t));
rsp.attr_value.handle = param->read.handle;
rsp.attr_value.len = 4;
rsp.attr_value.value[0] = 0xde;
rsp.attr_value.value[1] = 0xed;
rsp.attr_value.value[2] = 0xbe;
rsp.attr_value.value[3] = 0xef;
esp_ble_gatts_send_response(gatts_if, param->read.conn_id, param->read.trans_id,
ESP_GATT_OK, &rsp);
break;
}
case ESP_GATTS_WRITE_EVT: {
ESP_LOGI(GATTS_TAG, "GATT_WRITE_EVT, conn_id %d, trans_id %" PRIu32 ", handle %d", param->write.conn_id, param->write.trans_id, param->write.handle);
if (!param->write.is_prep){
// Assume the value is a single byte
ESP_LOGI(GATTS_TAG, "GATT_WRITE_EVT, value len %d, value :", param->write.len);
uint8_t received_value = param->write.value[0];
control_led(received_value);
}
example_write_event_env(gatts_if, &a_prepare_write_env, param);
break;
}
case ESP_GATTS_EXEC_WRITE_EVT:
ESP_LOGI(GATTS_TAG,"ESP_GATTS_EXEC_WRITE_EVT");
esp_ble_gatts_send_response(gatts_if, param->write.conn_id, param->write.trans_id, ESP_GATT_OK, NULL);
example_exec_write_event_env(&a_prepare_write_env, param);
break;
case ESP_GATTS_MTU_EVT:
ESP_LOGI(GATTS_TAG, "ESP_GATTS_MTU_EVT, MTU %d", param->mtu.mtu);
break;
case ESP_GATTS_UNREG_EVT:
break;
case ESP_GATTS_CREATE_EVT:
ESP_LOGI(GATTS_TAG, "CREATE_SERVICE_EVT, status %d, service_handle %d\n", param->create.status, param->create.service_handle);
gl_profile_tab[PROFILE_A_APP_ID].service_handle = param->create.service_handle;
gl_profile_tab[PROFILE_A_APP_ID].char_uuid.len = ESP_UUID_LEN_16;
gl_profile_tab[PROFILE_A_APP_ID].char_uuid.uuid.uuid16 = GATTS_CHAR_UUID_TEST_A;
esp_ble_gatts_start_service(gl_profile_tab[PROFILE_A_APP_ID].service_handle);
a_property = ESP_GATT_CHAR_PROP_BIT_READ | ESP_GATT_CHAR_PROP_BIT_WRITE | ESP_GATT_CHAR_PROP_BIT_NOTIFY;
esp_err_t add_char_ret = esp_ble_gatts_add_char(gl_profile_tab[PROFILE_A_APP_ID].service_handle, &gl_profile_tab[PROFILE_A_APP_ID].char_uuid,
ESP_GATT_PERM_READ | ESP_GATT_PERM_WRITE,
a_property,
&gatts_demo_char1_val, NULL);
if (add_char_ret){
ESP_LOGE(GATTS_TAG, "add char failed, error code =%x",add_char_ret);
}
break;
case ESP_GATTS_ADD_INCL_SRVC_EVT:
break;
case ESP_GATTS_ADD_CHAR_EVT: {
uint16_t length = 0;
const uint8_t *prf_char;
ESP_LOGI(GATTS_TAG, "ADD_CHAR_EVT, status %d, attr_handle %d, service_handle %d\n",
param->add_char.status, param->add_char.attr_handle, param->add_char.service_handle);
gl_profile_tab[PROFILE_A_APP_ID].char_handle = param->add_char.attr_handle;
gl_profile_tab[PROFILE_A_APP_ID].descr_uuid.len = ESP_UUID_LEN_16;
gl_profile_tab[PROFILE_A_APP_ID].descr_uuid.uuid.uuid16 = ESP_GATT_UUID_CHAR_CLIENT_CONFIG;
esp_err_t get_attr_ret = esp_ble_gatts_get_attr_value(param->add_char.attr_handle, &length, &prf_char);
if (get_attr_ret == ESP_FAIL){
ESP_LOGE(GATTS_TAG, "ILLEGAL HANDLE");
}
ESP_LOGI(GATTS_TAG, "the gatts demo char length = %x\n", length);
for(int i = 0; i < length; i++){
ESP_LOGI(GATTS_TAG, "prf_char[%x] =%x\n",i,prf_char[i]);
}
esp_err_t add_descr_ret = esp_ble_gatts_add_char_descr(gl_profile_tab[PROFILE_A_APP_ID].service_handle, &gl_profile_tab[PROFILE_A_APP_ID].descr_uuid,
ESP_GATT_PERM_READ | ESP_GATT_PERM_WRITE, NULL, NULL);
if (add_descr_ret){
ESP_LOGE(GATTS_TAG, "add char descr failed, error code =%x", add_descr_ret);
}
break;
}
case ESP_GATTS_ADD_CHAR_DESCR_EVT:
gl_profile_tab[PROFILE_A_APP_ID].descr_handle = param->add_char_descr.attr_handle;
ESP_LOGI(GATTS_TAG, "ADD_DESCR_EVT, status %d, attr_handle %d, service_handle %d\n",
param->add_char_descr.status, param->add_char_descr.attr_handle, param->add_char_descr.service_handle);
break;
case ESP_GATTS_DELETE_EVT:
break;
case ESP_GATTS_START_EVT:
ESP_LOGI(GATTS_TAG, "SERVICE_START_EVT, status %d, service_handle %d\n",
param->start.status, param->start.service_handle);
break;
case ESP_GATTS_STOP_EVT:
break;
case ESP_GATTS_CONNECT_EVT: {
esp_ble_conn_update_params_t conn_params = {0};
memcpy(conn_params.bda, param->connect.remote_bda, sizeof(esp_bd_addr_t));
/* For the IOS system, please reference the apple official documents about the ble connection parameters restrictions. */
conn_params.latency = 0;
conn_params.max_int = 0x20; // max_int = 0x20*1.25ms = 40ms
conn_params.min_int = 0x10; // min_int = 0x10*1.25ms = 20ms
conn_params.timeout = 400; // timeout = 400*10ms = 4000ms
ESP_LOGI(GATTS_TAG, "ESP_GATTS_CONNECT_EVT, conn_id %d, remote %02x:%02x:%02x:%02x:%02x:%02x:",
param->connect.conn_id,
param->connect.remote_bda[0], param->connect.remote_bda[1], param->connect.remote_bda[2],
param->connect.remote_bda[3], param->connect.remote_bda[4], param->connect.remote_bda[5]);
gl_profile_tab[PROFILE_A_APP_ID].conn_id = param->connect.conn_id;
//start sent the update connection parameters to the peer device.
esp_ble_gap_update_conn_params(&conn_params);
break;
}
case ESP_GATTS_DISCONNECT_EVT:
ESP_LOGI(GATTS_TAG, "ESP_GATTS_DISCONNECT_EVT, disconnect reason 0x%x", param->disconnect.reason);
esp_ble_gap_start_advertising(&adv_params);
break;
case ESP_GATTS_CONF_EVT:
ESP_LOGI(GATTS_TAG, "ESP_GATTS_CONF_EVT, status %d attr_handle %d", param->conf.status, param->conf.handle);
if (param->conf.status != ESP_GATT_OK){
esp_log_buffer_hex(GATTS_TAG, param->conf.value, param->conf.len);
}
break;
case ESP_GATTS_OPEN_EVT:
case ESP_GATTS_CANCEL_OPEN_EVT:
case ESP_GATTS_CLOSE_EVT:
case ESP_GATTS_LISTEN_EVT:
case ESP_GATTS_CONGEST_EVT:
default:
break;
}
}
static void gatts_profile_b_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_if, esp_ble_gatts_cb_param_t *param) {
switch (event) {
case ESP_GATTS_REG_EVT:
ESP_LOGI(GATTS_TAG, "REGISTER_APP_EVT, status %d, app_id %d\n", param->reg.status, param->reg.app_id);
gl_profile_tab[PROFILE_B_APP_ID].service_id.is_primary = true;
gl_profile_tab[PROFILE_B_APP_ID].service_id.id.inst_id = 0x00;
gl_profile_tab[PROFILE_B_APP_ID].service_id.id.uuid.len = ESP_UUID_LEN_16;
gl_profile_tab[PROFILE_B_APP_ID].service_id.id.uuid.uuid.uuid16 = GATTS_SERVICE_UUID_TEST_B;
esp_ble_gatts_create_service(gatts_if, &gl_profile_tab[PROFILE_B_APP_ID].service_id, GATTS_NUM_HANDLE_TEST_B);
break;
case ESP_GATTS_READ_EVT: {
ESP_LOGI(GATTS_TAG, "GATT_READ_EVT, conn_id %d, trans_id %" PRIu32 ", handle %d\n", param->read.conn_id, param->read.trans_id, param->read.handle);
esp_gatt_rsp_t rsp;
memset(&rsp, 0, sizeof(esp_gatt_rsp_t));
rsp.attr_value.handle = param->read.handle;
rsp.attr_value.len = 4;
rsp.attr_value.value[0] = 0xde;
rsp.attr_value.value[1] = 0xed;
rsp.attr_value.value[2] = 0xbe;
rsp.attr_value.value[3] = 0xef;
esp_ble_gatts_send_response(gatts_if, param->read.conn_id, param->read.trans_id,
ESP_GATT_OK, &rsp);
break;
}
case ESP_GATTS_WRITE_EVT: {
ESP_LOGI(GATTS_TAG, "GATT_WRITE_EVT, conn_id %d, trans_id %" PRIu32 ", handle %d\n", param->write.conn_id, param->write.trans_id, param->write.handle);
if (!param->write.is_prep){
// Assume the value is a single byte
uint8_t received_value = param->write.value[0];
control_led(received_value);
}
example_write_event_env(gatts_if, &b_prepare_write_env, param);
break;
}
case ESP_GATTS_EXEC_WRITE_EVT:
ESP_LOGI(GATTS_TAG,"ESP_GATTS_EXEC_WRITE_EVT");
esp_ble_gatts_send_response(gatts_if, param->write.conn_id, param->write.trans_id, ESP_GATT_OK, NULL);
example_exec_write_event_env(&b_prepare_write_env, param);
break;
case ESP_GATTS_MTU_EVT:
ESP_LOGI(GATTS_TAG, "ESP_GATTS_MTU_EVT, MTU %d", param->mtu.mtu);
break;
case ESP_GATTS_UNREG_EVT:
break;
case ESP_GATTS_CREATE_EVT:
ESP_LOGI(GATTS_TAG, "CREATE_SERVICE_EVT, status %d, service_handle %d\n", param->create.status, param->create.service_handle);
gl_profile_tab[PROFILE_B_APP_ID].service_handle = param->create.service_handle;
gl_profile_tab[PROFILE_B_APP_ID].char_uuid.len = ESP_UUID_LEN_16;
gl_profile_tab[PROFILE_B_APP_ID].char_uuid.uuid.uuid16 = GATTS_CHAR_UUID_TEST_B;
esp_ble_gatts_start_service(gl_profile_tab[PROFILE_B_APP_ID].service_handle);
b_property = ESP_GATT_CHAR_PROP_BIT_READ | ESP_GATT_CHAR_PROP_BIT_WRITE | ESP_GATT_CHAR_PROP_BIT_NOTIFY;
esp_err_t add_char_ret =esp_ble_gatts_add_char( gl_profile_tab[PROFILE_B_APP_ID].service_handle, &gl_profile_tab[PROFILE_B_APP_ID].char_uuid,
ESP_GATT_PERM_READ | ESP_GATT_PERM_WRITE,
b_property,
NULL, NULL);
if (add_char_ret){
ESP_LOGE(GATTS_TAG, "add char failed, error code =%x",add_char_ret);
}
break;
case ESP_GATTS_ADD_INCL_SRVC_EVT:
break;
case ESP_GATTS_ADD_CHAR_EVT:
ESP_LOGI(GATTS_TAG, "ADD_CHAR_EVT, status %d, attr_handle %d, service_handle %d\n",
param->add_char.status, param->add_char.attr_handle, param->add_char.service_handle);
gl_profile_tab[PROFILE_B_APP_ID].char_handle = param->add_char.attr_handle;
gl_profile_tab[PROFILE_B_APP_ID].descr_uuid.len = ESP_UUID_LEN_16;
gl_profile_tab[PROFILE_B_APP_ID].descr_uuid.uuid.uuid16 = ESP_GATT_UUID_CHAR_CLIENT_CONFIG;
esp_ble_gatts_add_char_descr(gl_profile_tab[PROFILE_B_APP_ID].service_handle, &gl_profile_tab[PROFILE_B_APP_ID].descr_uuid,
ESP_GATT_PERM_READ | ESP_GATT_PERM_WRITE,
NULL, NULL);
break;
case ESP_GATTS_ADD_CHAR_DESCR_EVT:
gl_profile_tab[PROFILE_B_APP_ID].descr_handle = param->add_char_descr.attr_handle;
ESP_LOGI(GATTS_TAG, "ADD_DESCR_EVT, status %d, attr_handle %d, service_handle %d\n",
param->add_char_descr.status, param->add_char_descr.attr_handle, param->add_char_descr.service_handle);
break;
case ESP_GATTS_DELETE_EVT:
break;
case ESP_GATTS_START_EVT:
ESP_LOGI(GATTS_TAG, "SERVICE_START_EVT, status %d, service_handle %d\n",
param->start.status, param->start.service_handle);
break;
case ESP_GATTS_STOP_EVT:
break;
case ESP_GATTS_CONNECT_EVT:
ESP_LOGI(GATTS_TAG, "CONNECT_EVT, conn_id %d, remote %02x:%02x:%02x:%02x:%02x:%02x:",
param->connect.conn_id,
param->connect.remote_bda[0], param->connect.remote_bda[1], param->connect.remote_bda[2],
param->connect.remote_bda[3], param->connect.remote_bda[4], param->connect.remote_bda[5]);
gl_profile_tab[PROFILE_B_APP_ID].conn_id = param->connect.conn_id;
break;
case ESP_GATTS_CONF_EVT:
ESP_LOGI(GATTS_TAG, "ESP_GATTS_CONF_EVT status %d attr_handle %d", param->conf.status, param->conf.handle);
if (param->conf.status != ESP_GATT_OK){
esp_log_buffer_hex(GATTS_TAG, param->conf.value, param->conf.len);
}
break;
case ESP_GATTS_DISCONNECT_EVT:
case ESP_GATTS_OPEN_EVT:
case ESP_GATTS_CANCEL_OPEN_EVT:
case ESP_GATTS_CLOSE_EVT:
case ESP_GATTS_LISTEN_EVT:
case ESP_GATTS_CONGEST_EVT:
default:
break;
}
}
static void gatts_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_if, esp_ble_gatts_cb_param_t *param)
{
/* If event is register event, store the gatts_if for each profile */
if (event == ESP_GATTS_REG_EVT) {
if (param->reg.status == ESP_GATT_OK) {
gl_profile_tab[param->reg.app_id].gatts_if = gatts_if;
} else {
ESP_LOGI(GATTS_TAG, "Reg app failed, app_id %04x, status %d\n",
param->reg.app_id,
param->reg.status);
return;
}
}
/* If the gatts_if equal to profile A, call profile A cb handler,
* so here call each profile's callback */
do {
int idx;
for (idx = 0; idx < PROFILE_NUM; idx++) {
if (gatts_if == ESP_GATT_IF_NONE || /* ESP_GATT_IF_NONE, not specify a certain gatt_if, need to call every profile cb function */
gatts_if == gl_profile_tab[idx].gatts_if) {
if (gl_profile_tab[idx].gatts_cb) {
gl_profile_tab[idx].gatts_cb(event, gatts_if, param);
}
}
}
} while (0);
}
void app_main(void)
{
esp_err_t ret;
// Configure the GPIO pins for output
gpio_set_direction(RED_LED, GPIO_MODE_OUTPUT);
gpio_set_direction(ORANGE_LED, GPIO_MODE_OUTPUT);
gpio_set_direction(GREEN_LED, GPIO_MODE_OUTPUT);
gpio_set_direction(VIBRATE_GPIO, GPIO_MODE_OUTPUT);
// Initialize NVS.
ret = nvs_flash_init();
if (ret == ESP_ERR_NVS_NO_FREE_PAGES || ret == ESP_ERR_NVS_NEW_VERSION_FOUND) {
ESP_ERROR_CHECK(nvs_flash_erase());
ret = nvs_flash_init();
}
ESP_ERROR_CHECK( ret );
ESP_ERROR_CHECK(esp_bt_controller_mem_release(ESP_BT_MODE_CLASSIC_BT));
esp_bt_controller_config_t bt_cfg = BT_CONTROLLER_INIT_CONFIG_DEFAULT();
ret = esp_bt_controller_init(&bt_cfg);
if (ret) {
ESP_LOGE(GATTS_TAG, "%s initialize controller failed: %s\n", __func__, esp_err_to_name(ret));
return;
}
ret = esp_bt_controller_enable(ESP_BT_MODE_BLE);
if (ret) {
ESP_LOGE(GATTS_TAG, "%s enable controller failed: %s\n", __func__, esp_err_to_name(ret));
return;
}
ret = esp_bluedroid_init();
if (ret) {
ESP_LOGE(GATTS_TAG, "%s init bluetooth failed: %s\n", __func__, esp_err_to_name(ret));
return;
}
ret = esp_bluedroid_enable();
if (ret) {
ESP_LOGE(GATTS_TAG, "%s enable bluetooth failed: %s\n", __func__, esp_err_to_name(ret));
return;
}
ret = esp_ble_gatts_register_callback(gatts_event_handler);
if (ret){
ESP_LOGE(GATTS_TAG, "gatts register error, error code = %x", ret);
return;
}
ret = esp_ble_gap_register_callback(gap_event_handler);
if (ret){
ESP_LOGE(GATTS_TAG, "gap register error, error code = %x", ret);
return;
}
ret = esp_ble_gatts_app_register(PROFILE_A_APP_ID);
if (ret){
ESP_LOGE(GATTS_TAG, "gatts app register error, error code = %x", ret);
return;
}
ret = esp_ble_gatts_app_register(PROFILE_B_APP_ID);
if (ret){
ESP_LOGE(GATTS_TAG, "gatts app register error, error code = %x", ret);
return;
}
esp_err_t local_mtu_ret = esp_ble_gatt_set_local_mtu(500);
if (local_mtu_ret){
ESP_LOGE(GATTS_TAG, "set local MTU failed, error code = %x", local_mtu_ret);
}
while(1) {
// Turn the GPIOs on
// gpio_set_level(RED_LED, 1);
// gpio_set_level(ORANGE_LED, 1);
// gpio_set_level(GREEN_LED, 1);
//
// vTaskDelay(1000 / portTICK_PERIOD_MS);
//
// // Turn the GPIOs off
// gpio_set_level(RED_LED, 0);
// gpio_set_level(ORANGE_LED, 0);
// gpio_set_level(GREEN_LED, 0);
//
vTaskDelay(1000 / portTICK_PERIOD_MS);
}
return;
}
Application Programming
OK, now I have a smart ring that changes its state based on Bluetooth commands. I thus far have controlled it using LightBlue by PunchThrough, which is my favourite Android app of all time right after "Easy Voice Recorder" and "gpslogger".
Boom boom pow write that Android app, connect that BLE, write to that characteristic, make that button that triggers the function that writes to that characteristic, woohoo now we have that done too.