fix(ulp): improve ULP examples for users using usb-jtag-serial

When using USB-serial-jtag for monitoring idf-monitor will lose connection
during deep sleep (because the peripheral powers down) and will need
some time to reconnect when we wake-up. In the ULP examples this would result in
the chip waking up->printing-> going back to sleep, before idf-monitor is even able
to connect, and users would erroneously assume the chip never woke up.

Add a 1 sec delay at the start of the examples to improve the user experience when
using jtag-serial.

examples/system/ulp/lp_core/gpio/main/lp_core_gpio_example_main.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2023-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -30,6 +30,13 @@ static void init_ulp_program(void);
 
 void app_main(void)
 {
+    /* If user is using USB-serial-jtag then idf monitor needs some time to
+    *  re-connect to the USB port. We wait 1 sec here to allow for it to make the reconnection
+    *  before we print anything. Otherwise the chip will go back to sleep again before the user
+    *  has time to monitor any output.
+    */
+    vTaskDelay(pdMS_TO_TICKS(1000));
+
     /* Initialize selected GPIO as RTC IO, enable input, disable pullup and pulldown */
     rtc_gpio_init(WAKEUP_PIN);
     rtc_gpio_set_direction(WAKEUP_PIN, RTC_GPIO_MODE_INPUT_ONLY);

examples/system/ulp/lp_core/lp_i2c/main/lp_i2c_main.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2023-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -9,6 +9,8 @@
 #include "lp_core_main.h"
 #include "ulp_lp_core.h"
 #include "lp_core_i2c.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
 
 extern const uint8_t lp_core_main_bin_start[] asm("_binary_lp_core_main_bin_start");
 extern const uint8_t lp_core_main_bin_end[]   asm("_binary_lp_core_main_bin_end");
@@ -53,6 +55,13 @@ static void lp_i2c_init(void)
 
 void app_main(void)
 {
+    /* If user is using USB-serial-jtag then idf monitor needs some time to
+    *  re-connect to the USB port. We wait 1 sec here to allow for it to make the reconnection
+    *  before we print anything. Otherwise the chip will go back to sleep again before the user
+    *  has time to monitor any output.
+    */
+    vTaskDelay(pdMS_TO_TICKS(1000));
+
     esp_sleep_wakeup_cause_t cause = esp_sleep_get_wakeup_cause();
     if (cause != ESP_SLEEP_WAKEUP_ULP) {
         printf("Not an LP core wakeup. Cause = %d\n", cause);

examples/system/ulp/lp_core/lp_uart/lp_uart_echo/main/lp_uart_main.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2023-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -10,6 +10,8 @@
 #include "lp_core_main.h"
 #include "ulp_lp_core.h"
 #include "lp_core_uart.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
 
 extern const uint8_t lp_core_main_bin_start[] asm("_binary_lp_core_main_bin_start");
 extern const uint8_t lp_core_main_bin_end[]   asm("_binary_lp_core_main_bin_end");
@@ -41,6 +43,13 @@ static void lp_core_init(void)
 
 void app_main(void)
 {
+    /* If user is using USB-serial-jtag then idf monitor needs some time to
+    *  re-connect to the USB port. We wait 1 sec here to allow for it to make the reconnection
+    *  before we print anything. Otherwise the chip will go back to sleep again before the user
+    *  has time to monitor any output.
+    */
+    vTaskDelay(pdMS_TO_TICKS(1000));
+
     esp_sleep_wakeup_cause_t cause = esp_sleep_get_wakeup_cause();
     if (cause != ESP_SLEEP_WAKEUP_ULP) {
         printf("Not an LP core wakeup. Cause = %d\n", cause);

examples/system/ulp/lp_core/lp_uart/lp_uart_print/main/lp_uart_main.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2023-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -10,6 +10,8 @@
 #include "lp_core_main.h"
 #include "ulp_lp_core.h"
 #include "lp_core_uart.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
 
 extern const uint8_t lp_core_main_bin_start[] asm("_binary_lp_core_main_bin_start");
 extern const uint8_t lp_core_main_bin_end[]   asm("_binary_lp_core_main_bin_end");
@@ -42,6 +44,13 @@ static void lp_core_init(void)
 
 void app_main(void)
 {
+    /* If user is using USB-serial-jtag then idf monitor needs some time to
+    *  re-connect to the USB port. We wait 1 sec here to allow for it to make the reconnection
+    *  before we print anything. Otherwise the chip will go back to sleep again before the user
+    *  has time to monitor any output.
+    */
+    vTaskDelay(pdMS_TO_TICKS(1000));
+
     esp_sleep_wakeup_cause_t cause = esp_sleep_get_wakeup_cause();
     if (cause != ESP_SLEEP_WAKEUP_ULP) {
         printf("Not an LP core wakeup. Cause = %d\n", cause);

examples/system/ulp/ulp_fsm/ulp/main/ulp_example_main.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2023-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -24,6 +24,8 @@
 #include "driver/rtc_io.h"
 #include "ulp.h"
 #include "ulp_main.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
 
 extern const uint8_t ulp_main_bin_start[] asm("_binary_ulp_main_bin_start");
 extern const uint8_t ulp_main_bin_end[]   asm("_binary_ulp_main_bin_end");
@@ -33,6 +35,13 @@ static void update_pulse_count(void);
 
 void app_main(void)
 {
+    /* If user is using USB-serial-jtag then idf monitor needs some time to
+    *  re-connect to the USB port. We wait 1 sec here to allow for it to make the reconnection
+    *  before we print anything. Otherwise the chip will go back to sleep again before the user
+    *  has time to monitor any output.
+    */
+    vTaskDelay(pdMS_TO_TICKS(1000));
+
     esp_sleep_wakeup_cause_t cause = esp_sleep_get_wakeup_cause();
     if (cause != ESP_SLEEP_WAKEUP_ULP) {
         printf("Not ULP wakeup, initializing ULP\n");

examples/system/ulp/ulp_fsm/ulp_adc/main/ulp_adc_example_main.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2023-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -44,6 +44,13 @@ static void start_ulp_program(void);
 
 void app_main(void)
 {
+    /* If user is using USB-serial-jtag then idf monitor needs some time to
+    *  re-connect to the USB port. We wait 1 sec here to allow for it to make the reconnection
+    *  before we print anything. Otherwise the chip will go back to sleep again before the user
+    *  has time to monitor any output.
+    */
+    vTaskDelay(pdMS_TO_TICKS(1000));
+
     esp_sleep_wakeup_cause_t cause = esp_sleep_get_wakeup_cause();
     if (cause != ESP_SLEEP_WAKEUP_ULP) {
         printf("Not ULP wakeup\n");

examples/system/ulp/ulp_riscv/adc/main/ulp_riscv_adc_example_main.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -19,6 +19,8 @@
 #include "ulp_adc.h"
 #include "ulp_main.h"
 #include "ulp/example_config.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
 
 
 extern const uint8_t ulp_main_bin_start[] asm("_binary_ulp_main_bin_start");
@@ -28,6 +30,12 @@ static void init_ulp_program(void);
 
 void app_main(void)
 {
+    /* If user is using USB-serial-jtag then idf monitor needs some time to
+    *  re-connect to the USB port. We wait 1 sec here to allow for it to make the reconnection
+    *  before we print anything. Otherwise the chip will go back to sleep again before the user
+    *  has time to monitor any output.
+    */
+    vTaskDelay(pdMS_TO_TICKS(1000));
 
     esp_sleep_wakeup_cause_t cause = esp_sleep_get_wakeup_cause();
 

examples/system/ulp/ulp_riscv/ds18b20_onewire/main/ulp_riscv_ds18b20_example_main.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2023-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -37,6 +37,13 @@ static void init_ulp_program(void);
 
 void app_main(void)
 {
+    /* If user is using USB-serial-jtag then idf monitor needs some time to
+    *  re-connect to the USB port. We wait 1 sec here to allow for it to make the reconnection
+    *  before we print anything. Otherwise the chip will go back to sleep again before the user
+    *  has time to monitor any output.
+    */
+    vTaskDelay(pdMS_TO_TICKS(1000));
+
     esp_sleep_wakeup_cause_t cause = esp_sleep_get_wakeup_cause();
     /* not a wakeup from ULP, load the firmware */
     if (cause != ESP_SLEEP_WAKEUP_ULP) {

examples/system/ulp/ulp_riscv/gpio/main/ulp_riscv_example_main.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2023-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -31,6 +31,13 @@ static void init_ulp_program(void);
 
 void app_main(void)
 {
+    /* If user is using USB-serial-jtag then idf monitor needs some time to
+    *  re-connect to the USB port. We wait 1 sec here to allow for it to make the reconnection
+    *  before we print anything. Otherwise the chip will go back to sleep again before the user
+    *  has time to monitor any output.
+    */
+    vTaskDelay(pdMS_TO_TICKS(1000));
+
     /* Initialize selected GPIO as RTC IO, enable input, disable pullup and pulldown */
     rtc_gpio_init(GPIO_NUM_0);
     rtc_gpio_set_direction(GPIO_NUM_0, RTC_GPIO_MODE_INPUT_ONLY);

examples/system/ulp/ulp_riscv/gpio_interrupt/main/ulp_riscv_gpio_intr_example_main.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -42,6 +42,13 @@ static void wakeup_gpio_init(void)
 
 void app_main(void)
 {
+    /* If user is using USB-serial-jtag then idf monitor needs some time to
+    *  re-connect to the USB port. We wait 1 sec here to allow for it to make the reconnection
+    *  before we print anything. Otherwise the chip will go back to sleep again before the user
+    *  has time to monitor any output.
+    */
+    vTaskDelay(pdMS_TO_TICKS(1000));
+
     esp_sleep_wakeup_cause_t cause = esp_sleep_get_wakeup_cause();
     /* not a wakeup from ULP, load the firmware */
     if (cause != ESP_SLEEP_WAKEUP_ULP) {

examples/system/ulp/ulp_riscv/i2c/main/ulp_riscv_rtc_i2c_example_main.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -38,6 +38,13 @@ static void init_i2c(void);
 
 void app_main(void)
 {
+    /* If user is using USB-serial-jtag then idf monitor needs some time to
+    *  re-connect to the USB port. We wait 1 sec here to allow for it to make the reconnection
+    *  before we print anything. Otherwise the chip will go back to sleep again before the user
+    *  has time to monitor any output.
+    */
+    vTaskDelay(pdMS_TO_TICKS(1000));
+
     uint8_t data_rd = 0;
     int16_t ut_data = 0;
     int32_t up_data = 0;

examples/system/ulp/ulp_riscv/touch/main/ulp_riscv_touch_example_main.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2023-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -76,6 +76,13 @@ static void init_ulp_program(void)
 
 void app_main(void)
 {
+    /* If user is using USB-serial-jtag then idf monitor needs some time to
+    *  re-connect to the USB port. We wait 1 sec here to allow for it to make the reconnection
+    *  before we print anything. Otherwise the chip will go back to sleep again before the user
+    *  has time to monitor any output.
+    */
+    vTaskDelay(pdMS_TO_TICKS(1000));
+
     esp_sleep_wakeup_cause_t cause = esp_sleep_get_wakeup_cause();
     /* not a wakeup from ULP, load the firmware */
     if (cause != ESP_SLEEP_WAKEUP_ULP) {

examples/system/ulp/ulp_riscv/uart_print/main/ulp_riscv_example_main.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -26,6 +26,13 @@ static void init_ulp_program(void);
 
 void app_main(void)
 {
+    /* If user is using USB-serial-jtag then idf monitor needs some time to
+    *  re-connect to the USB port. We wait 1 sec here to allow for it to make the reconnection
+    *  before we print anything. Otherwise the chip will go back to sleep again before the user
+    *  has time to monitor any output.
+    */
+    vTaskDelay(pdMS_TO_TICKS(1000));
+
     esp_sleep_wakeup_cause_t cause = esp_sleep_get_wakeup_cause();
     /* not a wakeup from ULP, load the firmware */
     if (cause != ESP_SLEEP_WAKEUP_ULP) {