esp_lte_modem

PPP over Serial (PPPoS) client library

Copy of the following repo with some additions (PIN submit, etc) for SIM7600x LTE modems.

https://github.com/espressif/esp-idf/tree/master/examples/protocols/pppos_client

CMUX multiplexer protocol

This repository contains additions from 4688 which allows the use of TCP/IP data streams and AT commands in parallel over one UART connection (two wire null modem).

Pin Assignment

The following pin assignments are used by default which can be changed in menuconfig.

ESP32	Cellular Modem
GPIO25	RX
GPIO26	TX
GND	GND
5V	VCC

UART buffers

I had some problems with UART buffers (especially CONFIG_EXAMPLE_MODEM_UART_RX_BUFFER_SIZE) below 16KB.

Usage in other projects

The library can be inserted into your own projects. Just checkout this repo to the root of your project and insert the folloing into the main CMakeLists.txt file:

list(APPEND EXTRA_COMPONENT_DIRS "esp_lte_modem/components/modem")
set(IDF_EXTRA_COMPONENT_DIRS ${EXTRA_COMPONENT_DIRS})

Monitor output

Monitor output from example (pppos_client_main.c):

I (383) cpu_start: Pro cpu start user code
I (383) cpu_start: Application information:
I (383) cpu_start: Project name:     pppos_client
I (389) cpu_start: App version:      34b5e4d-dirty
I (394) cpu_start: Compile time:     Jan 10 2021 14:40:39
I (400) cpu_start: ELF file SHA256:  140ea96103be123a...
I (406) cpu_start: ESP-IDF:          v4.3-dev-1197-g8bc19ba89
I (413) heap_init: Initializing. RAM available for dynamic allocation:
I (420) heap_init: At 3FFAE6E0 len 00001920 (6 KiB): DRAM
I (426) heap_init: At 3FFB3B48 len 0002C4B8 (177 KiB): DRAM
I (432) heap_init: At 3FFE0440 len 00003AE0 (14 KiB): D/IRAM
I (438) heap_init: At 3FFE4350 len 0001BCB0 (111 KiB): D/IRAM
I (445) heap_init: At 4008B9E4 len 0001461C (81 KiB): IRAM
I (452) spi_flash: detected chip: generic
I (456) spi_flash: flash io: dio
I (461) cpu_start: Starting scheduler on PRO CPU.
I (0) cpu_start: Starting scheduler on APP CPU.
I (474) uart: queue free spaces: 30
I (484) pppos_example: Trying to initialize modem on GPIO TX: 17 / RX: 16
W (564) esp-modem: Rx Break
E (1984) esp-modem: esp_modem_dte_send_cmd(417): process command timeout
E (1984) dce_service: esp_modem_dce_sync(67): send command failed
E (1984) bg96: bg96_init(539): sync failed
I (2484) pppos_example: Trying to initialize modem on GPIO TX: 17 / RX: 16
E (3984) esp-modem: esp_modem_dte_send_cmd(417): process command timeout
E (3984) dce_service: esp_modem_dce_sync(67): send command failed
E (3984) bg96: bg96_init(539): sync failed
I (4484) pppos_example: Trying to initialize modem on GPIO TX: 17 / RX: 16
E (5984) esp-modem: esp_modem_dte_send_cmd(417): process command timeout
E (5984) dce_service: esp_modem_dce_sync(67): send command failed
E (5984) bg96: bg96_init(539): sync failed
I (6484) pppos_example: Trying to initialize modem on GPIO TX: 17 / RX: 16
E (7984) esp-modem: esp_modem_dte_send_cmd(417): process command timeout
E (7984) dce_service: esp_modem_dce_sync(67): send command failed
E (7984) bg96: bg96_init(539): sync failed
I (8484) pppos_example: Trying to initialize modem on GPIO TX: 17 / RX: 16
E (9984) esp-modem: esp_modem_dte_send_cmd(417): process command timeout
E (9984) dce_service: esp_modem_dce_sync(67): send command failed
E (9984) bg96: bg96_init(539): sync failed
I (10484) pppos_example: Trying to initialize modem on GPIO TX: 17 / RX: 16
E (11804) esp-modem: esp_dte_handle_line(138): handle line failed
W (11804) pppos_example: Unknow line received: RDY

E (11984) esp-modem: esp_modem_dte_send_cmd(417): process command timeout
E (11984) dce_service: esp_modem_dce_sync(67): send command failed
E (11984) bg96: bg96_init(539): sync failed
E (12264) esp-modem: esp_dte_handle_line(137): no handler for line
W (12264) pppos_example: Unknow line received: +CPIN: SIM PIN

I (12484) pppos_example: Trying to initialize modem on GPIO TX: 17 / RX: 16
I (12534) bg96: CMUX setup
I (12934) bg96: PIN ASK response: +CPIN: SIM PIN

I (12934) bg96: SIM needs PIN
I (13034) bg96: PIN ASK response: OK

I (13034) bg96: submit PIN
I (13144) bg96: set PIN ok
E (13464) esp-modem: esp_dte_handle_line(137): no handler for line
W (13464) pppos_example: Unknow line received: +CPIN: READY

E (13904) esp-modem: esp_dte_handle_line(137): no handler for line
W (13904) pppos_example: Unknow line received: SMS DONE

E (14594) esp-modem: esp_dte_handle_line(138): handle line failed
W (14594) pppos_example: Unknow line received: PB DONE

I (15344) bg96: CMUX command success
I (15344) bg96: enter CMUX mode ok
I (15894) pppos_example: Module: SIMCOM_SIM7600E
I (15894) pppos_example: Operator: "xxx"
I (15894) pppos_example: IMEI: xxx
I (15894) pppos_example: IMSI: xxx
I (16004) pppos_example: rssi: 0, ber: 0
I (16864) pppos_example: Battery voltage: 0 mV
I (16864) esp-modem: APN: xxx
I (16964) esp-modem: PPP MODE
I (16964) esp-modem: Got ATD
I (17014) esp-modem: Handle Line: CONNECT 115200
|� 115200
|�t",7
 for DLCI 1
I (17014) DCE_TAG: ATD response: CONNECT 115200
|� 115200
|�t",7

I (17064) pppos_example: Modem PPP Started
I (17314) esp-netif_lwip-ppp: Connected
I (17314) esp-netif_lwip-ppp: Name Server1: x.x.x.x
I (17314) esp-netif_lwip-ppp: Name Server2: x.x.x.x
I (17314) pppos_example: Modem Connect to PPP Server
I (17324) pppos_example: ~~~~~~~~~~~~~~
I (17324) pppos_example: IP          : x.x.x.x
I (17334) pppos_example: Netmask     : 255.255.255.255
I (17334) pppos_example: Gateway     : x.x.x.x
I (17344) pppos_example: Name Server1: x.x.x.x
I (17344) pppos_example: Name Server2: x.x.x.x
I (17354) pppos_example: ~~~~~~~~~~~~~~
I (17354) pppos_example: GOT ip event!!!
I (17364) system_api: Base MAC address is not set
I (17364) system_api: read default base MAC address from EFUSE
I (17374) pppos_example: MQTT other event id: 7
I (17764) pppos_example: MQTT_EVENT_CONNECTED
I (17764) pppos_example: sent subscribe successful, msg_id=20524
I (17864) pppos_example: MQTT_EVENT_SUBSCRIBED, msg_id=20524
I (17864) pppos_example: sent publish successful, msg_id=0
I (17964) pppos_example: MQTT_EVENT_DATA
TOPIC=/topic/esp-pppos
DATA=esp32-pppos
I (18164) pppos_example: rssi: 0, ber: 0
I (23264) pppos_example: rssi: 0, ber: 0
I (28364) pppos_example: rssi: 0, ber: 0
I (33464) pppos_example: rssi: 0, ber: 0