ESP8266 not found after firmware update

[hanoba]

I am trying to use the ESP8266 module from the shop (with the additional 470uF capacitor) together with Sunray.

When using the module with the original firmware (version 1.5.4) the module was found:
[WiFiEsp] Initializing ESP module
[WiFiEsp] Initilization successful - 1.5.4
WiFi found!

However, it did not connect to my access point.

Therefore I made a firmware update to 2.2.1 (ESP8266_NONOS_SDK-2.2.1.zip) as described in the Sunray Wiki. The update worked without problems.

After the update, the module is no longer found and the following error message is shown in the console output:
WIFI (ESP8266) not found! If the problem persist, you may need to flash your ESP to firmware 2.2.1.

I hope someone can help...
Many thanks in advance!

 

[mw46d]

Do you have another 3.3V based Arduino (to play with the wifi module outside of the mower)? That might make debugging easier?!

I upgraded my modules as well and it works just fine

[WiFiEsp] Initializing ESP module
[WiFiEsp] Initilization successful - 2.2.1
WiFi found!
Attempting to connect to WPA SSID: mw_wXX
[WiFiEsp] Connected to mw_wXX
You're connected with SSID=mw_wXX and IP=192.168.1.132
[WiFiEsp] Server started on port 80

 

[hanoba]

I tested the ESP8266 module using the serial monitor of the Arduino IDE and a FTDI USB-to-serial interface (mower not involved). It outputs the correct boot loader message after reset, but does not respond to an AT command. It seems that my ESP8266 is broken. I already ordered a new one.

You wrote "I upgraded my modules as well". Does this mean that you made a ESP8266 firmware update? What was your firmware version before the update?

 

[mw46d]

good question:-( I bought some of those ESP8266 some years ago. Let's see, iff I still have one with the original firmware;-)

 

[hanoba]

Did you buy it from the ArduMower shop?

 

[mw46d]

No, they are rather old ones;-)

------------------------------------------------------------------
AT+RST

OK
c_⸮⸮RS⸮⸮FjS⸮fJ[⸮⸮⸮
[Vendor:www.ai-thinker.com Version:0.9.2.4]

ready
AT+GMR
0018000902-AI03

OK
-------------------------------------------------------------------

 

[hanoba]

After a lot of debugging and Google search I finally managed to flash the firmware 2.2.1!

The solution was:

• use DOUT flash mode during programming
• flash the boot loader "boot_v1.5.bin" and not the boot loader "boot_v1.7.bin" that is part of "ESP8266_NONOS_SDK-2.2.1.zip"

This is the output of the AT+GMR command for the new firmware:
AT version:1.6.2.0(Apr 13 2018 11:10:59)
SDK version:2.2.1(6ab97e9)
compile time:Jun 7 2018 19:34:26
Bin version(Wroom 02):1.6.2
OK

 

[mw46d]

Do you sill have some links for the next guy? ;-)

 

[hanoba]

The hint to use DOUT mode is included in this thread: https://github.com/esp8266/Arduino/issues/3753
I found out myself by trial and error to flash the boot loader "boot_v1.5.bin" instead of "boot_v1.7.bin".

 

[markor]

I am trying to use the ESP8266 module from the shop (with the additional 470uF capacitor) together with Sunray.

Thanks for the info. What capacitor are you talking about (470uF) ? I have updated my C13 to 100uF, but has the number risen again or are you talking about some other capacitor. I have old mowers without RTK and I'm about to start tinkering with the ESP. Thanks in advance.

 

[mw46d]

That's a capacitor directly on the ESP8266 module (between VCC & GND) to smooth out any spikes, the module might create. The value is not critical once 'large enough;-)

 

[hanoba]

The capacitor is described here: https://wiki.ardumower.de/index.php?title=Ardumower_Sunray#WiFi_module

 

[Fürst Ruprecht]

The capacitor is not well chosen. A large capacitor makes sense where the operating voltage fluctuates greatly due to the switched outputs. Here a tantalum capacitor of a few pF would be better for filtering high-frequency interference signals.
Gruß Fürst Ruprecht

 

[markor]

The capacitor is not well chosen. A large capacitor makes sense where the operating voltage fluctuates greatly due to the switched outputs. Here a tantalum capacitor of a few pF would be better for filtering high-frequency interference signals.
Gruß Fürst Ruprecht

@hanoba Thanks. @Fürst Ruprecht What I have read the ESP can be very power hungry and C13 (!½22uF is recommended to be replaced with at least 100uF capacitor to let the ESP draw all it needs in spikes.

 

[markor]

The capacitor is not well chosen. A large capacitor makes sense where the operating voltage fluctuates greatly due to the switched outputs. Here a tantalum capacitor of a few pF would be better for filtering high-frequency interference signals.
Gruß Fürst Ruprecht

@hanoba Thanks. @Fürst Ruprecht What I have read the ESP can be very power hungry and C13 ("power bank") 22uF is recommended to be replaced with at least 100uF capacitor to let the ESP draw all it needs in spikes.

But is this not enough, the C13 100uF? Does it really need an extra capacitor at the ESP itself?

 

[hanoba]

I assume 100µF are sufficient. I have a small ESP8266 USB programming board. This board also has only a 100µF capacitor.
I had problems with the ESP8266 that were caused by an old ESP8266 firmware, but not by a too small capacitor.