How to restart pppos client? (IDFGH-2105) (IDFGH-2106)

[sim-pixel]

Environment

• Module or chip used:
  ESP32-WROOM-32U
• IDF version:
  v3.3
• Build System:
  CMake
• Operating System:
  Windows 10
• Power Supply:
  USB

Problem Description

I'm trying to develop a function that restart the pppos client every X seconds.

I take the code from you repo (https://github.com/espressif/esp-idf/blob/master/examples/protocols/pppos_client/main/pppos_client_main.c).
I just changed the function name from "app_main()" to "pppos_init()", so this is my function (in pppos.c):
void pppos_init()
{
tcpip_adapter_init();
event_group = xEventGroupCreate();
/* create dte object */
esp_modem_dte_config_t config = ESP_MODEM_DTE_DEFAULT_CONFIG();
modem_dte_t *dte = esp_modem_dte_init(&config);
// Register event handler //
ESP_ERROR_CHECK(esp_modem_add_event_handler(dte, modem_event_handler, NULL));
// create dce object //
#if CONFIG_ESP_MODEM_DEVICE_SIM800
modem_dce_t *dce = sim800_init(dte);
#elif CONFIG_ESP_MODEM_DEVICE_BG96
modem_dce_t *dce = bg96_init(dte);
#else
#error "Unsupported DCE"
#endif
ESP_ERROR_CHECK(dce->set_flow_ctrl(dce, MODEM_FLOW_CONTROL_NONE));
ESP_ERROR_CHECK(dce->store_profile(dce));
// Print Module ID, Operator, IMEI, IMSI //
ESP_LOGI(TAG, "Module: %s", dce->name);
ESP_LOGI(TAG, "Operator: %s", dce->oper);
ESP_LOGI(TAG, "IMEI: %s", dce->imei);
ESP_LOGI(TAG, "IMSI: %s", dce->imsi);
// Get signal quality //
uint32_t rssi = 0, ber = 0;
ESP_ERROR_CHECK(dce->get_signal_quality(dce, &rssi, &ber));
ESP_LOGI(TAG, "rssi: %d, ber: %d", rssi, ber);
// Get battery voltage //
uint32_t voltage = 0, bcs = 0, bcl = 0;
ESP_ERROR_CHECK(dce->get_battery_status(dce, &bcs, &bcl, &voltage));
ESP_LOGI(TAG, "Battery voltage: %d mV", voltage);
// Setup PPP environment //
esp_modem_setup_ppp(dte, configuration_get(CONF_APN));
// Wait for IP address //
xEventGroupWaitBits(event_group, CONNECT_BIT, pdTRUE, pdTRUE, portMAX_DELAY);
// Config MQTT //
esp_mqtt_client_config_t mqtt_config = {
.uri = BROKER_URL,
.event_handle = mqtt_event_handler,
};
esp_mqtt_client_handle_t mqtt_client = esp_mqtt_client_init(&mqtt_config);
esp_mqtt_client_start(mqtt_client);
xEventGroupWaitBits(event_group, GOT_DATA_BIT, pdTRUE, pdTRUE, portMAX_DELAY);
esp_mqtt_client_destroy(mqtt_client);
// Exit PPP mode //
ESP_ERROR_CHECK(esp_modem_exit_ppp(dte));
xEventGroupWaitBits(event_group, STOP_BIT, pdTRUE, pdTRUE, portMAX_DELAY);
#if CONFIG_EXAMPLE_SEND_MSG
const char *message = "Welcome to ESP32!";
ESP_ERROR_CHECK(example_send_message_text(dce, CONFIG_EXAMPLE_SEND_MSG_PEER_PHONE_NUMBER, message));
ESP_LOGI(TAG, "Send send message [%s] ok", message);
#endif
// Power down module //
ESP_ERROR_CHECK(dce->power_down(dce));
ESP_LOGI(TAG, "Power down");
ESP_ERROR_CHECK(dce->deinit(dce));
ESP_ERROR_CHECK(dte->deinit(dte));
}

In my main function (main.c) I run the following function:
void app_main()
{
for(int i=0; i<5; i++){
vTaskDelay( 20000 / portTICK_PERIOD_MS );
pppos_init();
}
}

The first time (i=0) i can see "Modem PPP Started" and all data are sent via MQTT. At the second time (i=1) it stucks.

Any guidance will be helpful.
Thanks

[sim-pixel]

Any suggestions?

[AshUK]

Having issues with this too

I see that once MODEM_EVENT_PPP_DISCONNECT has been raised, esp_modem_exit_ppp causes the the task to wait

[MrCurio]

Having similiar issues to restart ppos client. Particularly, using trying to reinit the client causes crashing, anyway, i also posted a similar issue on github called: "PppoS: Uart Resync Problems". Hope they will fix this soon :)

[MrCurio]

Found some interesting info in #3506 !
It may not be thread safe but some people made it work, i will give it a try!

[vinifr]

During the ppp setup call pppapi_pppos_create and pppapi_set_default only 1 time. So when it is reconnecting skip these functions and call only pppapi_connect.

In exit it must call only pppapi_close. Do not call pppapi_free! That will solve the issue.

Example:

// Dont create ppp instance twice!!
if (!pppReconnect) {
    ppp = pppapi_pppos_create(&ppp_netif,
                            ppp_output_callback, ppp_status_cb, NULL);
    pppapi_set_default(ppp);
}
pppapi_connect(ppp, 0);

[diogoviannaaraujo]

Ive been trying to reconnect the ppp connection after a connection drop.

For my test I get a proper connection and then cover the modem with foil, after receiving PPPERR_PEERDEAD err_code on ppp_status_cb from missed LCP echo packages I remove foil cover, wait some seconds, and call only pppapi_connect(ppp, 0)

but it always just return PPPERR_PEERDEAD err_code again on ppp_status_cb.

Should I do all the chat script again after a connection drop?

[Alvin1Zhang]

@diogoviannaaraujo Thanks for reporting. Would you please help file a new ticket for the new issue? Thanks.