Wi-Fi softAP on a prototype has intermittent SSID and cannot conect

[bryanergy]

Wi-Fi Issue, hardware and software root causes?

Wi-Fi - single core softAP on v4.0.1, 4.3 (master), and v4.0.2, SSID shows up and connects, using DevKits ESP32-SOLO-1 or WROOM-32D or 32U

Same binary also works on U4WDH in two modified Solo-1 (removed S0WD, installed U4WDH).

Same binary fails Wi-Fi on my prototype using U4WDH as softAP.
SSID appears intermittently. I cannot connect to it from same machines that work with DevKit

I set for single core with menuconfig, and verbose debug, verbose Wi-Fi debug, etc., as seen below. I’ve built 4.0.1, master (4.3) and 4.0.2. All similar results.

To isolate, I disconnected other parts of circuit and power up only 3.3V and (USB supplied 5v for uart interface). I then see ets_main csum error in boot loader. Is there any obvious strapping problem here?

Code: Select all

csum err:0xba!=0x9a
ets_main.c 384 

When running on main power, boots up fine, no csum error, softAP debug messages appear (I enabled VERBOSE on several things in menuconfig). After I try to connect from laptop, I see nothing at all added to log, until 6 minutes later.

Code: Select all

W (1723712) wifi:inactive timer: now=669e5916 last_rx_time=54bcb5a6 diff=493e0, aid[0]98:af:65:33:xx:xx leave
I (1723712) wifi:max stations already connected to ap! <station>98:af:65:33:xx:xx, AID = 0
W (1723722) wifi:rm mis
I (1723722) wifi:new:<7,0>, old:<7,1>, ap:<7,1>, sta:<255,255>, prof:7
V (1723722) wifi:ht20 freq=2442, chan=7

This message is in libnet80211, in Espressif code that is not supplied in source code. The message is not part of freebsd net80211. I saw an earlier issue, but it’s not this because the default configuration does not depend on nvs. I did change MAX_STA_CONN to 4, this and the Wi-Fi password set, it’s impossible that any other stations are able to join the AP. So it’s not this.

WiFi AP max stations already connected #2357 (Sep 1, 2018)<br>
https://github.com/espressif/esp-idf/issues/2357

If I come back an hour later, try to connect again, again there is no debug output, until 6 minutes later, similar to the above is seen. Again half an hour or two hours later, I can do the same again. This would seem to be a software problem in libnet80211.a, except for the obvious problem I fail csum if I try to power only the ESP32 chip and USB. So I am thinking something is interfering with strapping or important thing happening on multi function pin.