using Nrf52 & Zephyr to connect to ESP8266

[Blue King]

Trying to compile samples/net/wifi/ to test the esp8266 with Nrf52. we have our custom board. but Im' testing using Nrf52840 DK now.

I've this file

in myProject/boards/nrf52840dk_nrf52840.overlay

&uart1{
    compatible = "nordic,nrf-uarte";
    status = "okay";
    current-speed = <115200>;
    tx-pin = <34>;
    rx-pin = <33>;
    esp8266{
        compatible = "espressif,esp-at";
        label = "esp8266";
        status = "okay";
    };
};

Followed this guide

https://docs.zephyrproject.org/2.4.0/boards/shields/esp_8266/doc/index.html  to connect the wires

currently, the Wifi Module works when I connect it to a USBtoTTL. so the esp8266 is flashed correctly and responding to AT commands.

the sample, never sees a WiFi device attached when I try this command

net iface

I get empty response.

when i tried

wifi scan

I get this

uart:~$ wifi scan

[00:00:05.041,503] <err> os: ***** MPU FAULT *****
[00:00:05.041,534] <err> os:   Instruction Access Violation
[00:00:05.041,534] <err> os: r0/a1:  0x000044b4  r1/a2:  0x000052a9  r2/a3:  0x00000000
[00:00:05.041,534] <err> os: r3/a4:  0x20004740 r12/ip:  0x00013c1f r14/lr:  0x000054dd
[00:00:05.041,564] <err> os:  xpsr:  0x60000000
[00:00:05.041,564] <err> os: Faulting instruction address (r15/pc): 0x20004740
[00:00:05.041,564] <err> os: >>> ZEPHYR FATAL ERROR 0: CPU exception on CPU 0
[00:00:05.041,564] <err> os: Current thread: 0x20000400 (shell_uart)
[00:00:06.019,805] <err> os: Halting system
*** Booting Zephyr OS build zephyr-v2.4.0-941-g933b4202355d  ***

Currently I'm connecting TX to P1.01 and RX to P1.02. to my TTL. expecting to see some data coming on boot (AT Commands sent to ESP8266)


Not sure what I'm doing wrong

highly appreciating your help

Thank you

[Didrik Rokhaug]

Hi,

This might just be a stack overflow. Could you try to increase CONFIG_SHELL_STACK_SIZE (default is 2048)?

Best regards,

Didrik

[Blue King]

I've tried this by doing the following

CONFIG_NET_TX_STACK_SIZE=4096
CONFIG_NET_RX_STACK_SIZE=4096
CONFIG_SHELL_STACK_SIZE=4096

still, the same result. never recieved any AT Commands (on the right side is my TTL). and still same problem

1. net iface shows no devices
2. wifi scan crashes

I think net iface should show device first

I used this to compile

west build -b nrf52840dk_nrf52840 -- -DSHIELD=esp_8266