Weird ESP32 problem with AccessPoint firmware

P

P. Short

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I'm having problems getting bespoke ESP01 firmware to associate with ESP32-mini.

The ESP01 associates fine with a TP=Link travel AccessPoint, as does a PC running Ubuntu.
The PC associates fine with the ESP32 running either the Arduino WiFiAccessPoint or the esp-idf softAP. firmware.
And ESP32S3 also associates fine with all the above AccessPoint implementations.
The ESP01 refuses to associate with either of the firmware versions of the ESP32-mini (neither fresh out of the box),
the ESP01S does associate with an ESP32 devkit running the same firmware as the mini's.

I've tried two different ESP32-mini boards, with the same results on both.

Thoughts?
 
The ESP01 is very sensitive to the bandwidth of the AP. It doesn't like 40mhz. So if you have an option to ensure it's in 20mhz mode, I think you'll have much better luck.
 
I made the change, no joy. The ESP01 associates with my TP-Link travel router, and ESP32S3 board without any problem. It also associates with an ESP32 Devkit board, which is similar to the ESP32 mini but with a lot more pins broken out.
 
iIs the Esp32 mini defaulting to a different channel .

GOOGLE GAVE ME THIS ->

cpp

esp_wifi_set_channel(1, WIFI_SECOND_CHAN_NONE);
 
Google says this is a known issue and offers some steps , the esp01 should be set to the same channel .
There is also mention of V drop a non stable V. the O1's need a good stable 3.3
 
RST & CH_PD: Ensure CH_PD (Chip Enable) is connected to 3.3V. If using an ESP-01S, this is handled internally, but standard ESP-01 boards require this pull-up resistor
 
I'm sure you know these tips already though.
I have a lot of the ESP32 mini and use them with WLED in sync mode .
The 16 pin foot print swaps perfectly with the Esp8266 mini and pro boards .

I gave up on esp01's do to limited output .
 
Yes, the WiFiAccessPoint example from the latest Arduino ide and the softAP example from the espressif IDE. Bear in mind that things work fine with a different model ESP32 dev board. And that ESP AP works fine with that laptop as well as an ESP32S3 board. Its only that one combination that doesn't work (with two different instances of the ESP board).
 
On the off chance you live by a lot of people, a microwave oven's strongest interference is centered on 2.45 GHz, which directly overlaps Wi-Fi channel 9.

According to Google, the ESP-01S modules are significantly more susceptible to microwave oven interference than many other microcontrollers. While all 2.4 GHz Wi-Fi devices (including ESP8266, ESP32, and IoT devices) are impacted, the ESP-01S has specific vulnerabilities.
 
ErnieHorning said:
On the off chance you live by a lot of people, a microwave oven's strongest interference is centered on 2.45 GHz, which directly overlaps Wi-Fi channel 9.

According to Google, the ESP-01S modules are significantly more susceptible to microwave oven interference than many other microcontrollers. While all 2.4 GHz Wi-Fi devices (including ESP8266, ESP32, and IoT devices) are impacted, the ESP-01S has specific vulnerabilities.
Click to expand...
googley eyes did say channel 1

cpp

esp_wifi_set_channel(1, WIFI_SECOND_CHAN_NONE);
 
Ernie, that strategy doesn't avoid interference, especially if everyone else within range is doing the same.
 
Well, running in the sidebands of others certainly isn't in your favor. While not as robust as Enterprise, commercial routers and their connected devices share a Wi-Fi channel primarily by taking turns to transmit data, a process known as contention-based access or CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance). Using a side channel just communicates through noise and has a lot more collisions.


Channels 1, 6, and 11 are considered the best for 2.4 GHz Wi-Fi networks in North America because they are the only three channels that do not overlap with each other. Using these non-overlapping channels reduces interference and improves network stability in crowded environments.

Key Reasons for 1, 6, and 11:
  • Non-Overlapping Frequencies: While the 2.4 GHz band has 11-14 available channels (depending on the region), each channel is 20 MHz wide, but they are spaced only 5 MHz apart. Using intermediate channels (like 2, 3, 4, 5, etc.) causes interference with both the channel below and above it.
  • Reduced Interference (CCI vs. ACI): Using 1, 6, or 11 results in Co-Channel Interference (CCI), where devices simply "wait their turn" to talk, which is manageable. Using overlapping channels causes Adjacent Channel Interference (ACI), which acts as noise and reduces the speed for all connected devices.
  • Standardization: In North America (FCC regulations), only channels 1-11 are typically available. Channels 1, 6, and 11 provide the maximum separation possible to avoid interference in this limited spectrum.
 
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