Here are some fragments from my code (which does not do anything useful yet, but does communicate with the ESP-32 to send its first command). I hope it is helpful.

Header file lilygo_tpicoc3.h

// Link to the ESPC3-C3 processor on the same board #define TPICOC3_ESP32C3_UART 1 #define TPICOC3_ESP32C3_TX_PIN 8 #define TPICOC3_ESP32C3_RX_PIN 9 #define TPICOC3_ESP32C3_CTS_PIN 10 #define TPICOC3_ESP32C3_RTS_PIN 11

Set up RP2040 UART to communicate

uart = uart_get_instance(TPICOC3_ESP32C3_UART); // The ESP32-C3 hardware can run its UARTs at up to 5 Mbaud uart_init(uart, 115200); // Default for ESP-AT's hardware reset (?) gpio_set_function(TPICOC3_ESP32C3_TX_PIN, GPIO_FUNC_UART); gpio_set_function(TPICOC3_ESP32C3_RX_PIN, GPIO_FUNC_UART); gpio_set_function(TPICOC3_ESP32C3_CTS_PIN, GPIO_FUNC_UART); gpio_set_function(TPICOC3_ESP32C3_RTS_PIN, GPIO_FUNC_UART); uart_set_hw_flow(uart, true, true); // Use CTS and RTS uart_set_format(uart,8,1,UART_PARITY_NONE);

From the communication code. Must wait a short time (120 ms for the screen to wake up is enough for the ESP-32 as well).

// Send command: starts with AT and must end with \r\n uart_puts(uart, "AT\r\n"); // Most commands are AT+...\r\n

Multi-line reply, ends with a full line OK\r\n or ERROR\r\n

@lewis Here are my results of current consumption w/o red LED. The blog post is in German but Google helps. 😉

https://ckarduino.wordpress.com/2022/05/16/lilygo-t-oi-plus-risc-v-esp32-c3/

The device works much longer now. It is a good idea to make the LED switchable in a redesign.

@ak Around 800uA

Schematics are already stored on Github

The purchase link has a pinout.

479330e5-d79c-41c6-8927-0433a9c5bf67-image.png

Just move the green original to the red position to use the external antenna

TTGO LoRa32 V2.1-1.6 is the same as TTGO LoRa32 V2.1-1.6.1, we just changed the silk screen on the board. The OLED on the board uses (SDA)21 , (SCL)22 There are schematic diagrams and reference codes in our warehouse, please see here Link

@andyclap When the battery is depleted, the noise source is from the DCDC boost inductor on the board, thanks for your feedback, I will discuss the solution with my team.
Recommendations on power consumption:

When starting T-Higrow, it is recommended to reduce the main frequency of ESP32 to 160, or lower, if not using WiFi, it is recommended to lower to 80, 40MHz If WiFi transmission is used, it is recommended to reduce the number of transmissions, and then package and send the data uniformly. The number of acquisitions can remain unchanged.

Thanks for your feedback.

Link

58498dd0-cd15-4a17-933d-2fe0cf5de84c-image.png

@chaymasa If you want to know the LoRa chip model used in T-Beam, you can check the link. If you need to write the version of LoRaWAN, you need to see the version supported by the software.

@jezerca said in 10000 mAh Li-Po battery with TTGO T-Call&PMU SIM800L ?:

Hi all,
Expect the long charging time, would there any problem to use such kind of battery? Does the AXP192 board support it?

Hi. You can use this 3.7V battery, the default charging current is 500ma, you can modify it by programming.

esp32 uses FFAT32, the file system supports up to 32G

@destroyedlolo Great idea, we actually already have a similar product. Such as T-SIM7000 series.