Search found 39 matches

by novalight
Mon Jun 25, 2018 10:48 am
Forum: Hardware
Topic: Reset vs Power Cycling
Replies: 2
Views: 365

Re: Reset vs Power Cycling

Hi, I am also interested in this. Also maybe: what are the differences between calling esp_restart() / esp_reboot() and EN-toggle?
by novalight
Thu Jun 21, 2018 8:40 pm
Forum: ESP32 IDF
Topic: Intermittent "sdmmc_read_blocks failed (263)" error
Replies: 0
Views: 134

Intermittent "sdmmc_read_blocks failed (263)" error

I have a custom board running a SD card in 4 wire mode. Sometimes I get "sdmmc_read_blocks failed (263)" error which is hard to reproduce. The SD-Traces are kept relatively short and the power supply is good. Next week I have the chance to measure some stuff. What are the software and/or h...
by novalight
Thu May 17, 2018 9:03 am
Forum: Hardware
Topic: Wifi performance poor despite strong (-9) RSSI, how debug/diagnose?
Replies: 18
Views: 1359

Re: Wifi performance poor despite strong (-9) RSSI, how debug/diagnose?

Mhh, I see this oscillator thing more like an "all or nothing"-problem. I mean it's a digital signal running through a 4-5mm bodge wire. The Vcc and GND connections are fine and it's properly decoupled. The 40 MHz Signal has slew rate control, so it should not radiate any harmonics and the...
by novalight
Thu May 17, 2018 6:43 am
Forum: Hardware
Topic: Wifi performance poor despite strong (-9) RSSI, how debug/diagnose?
Replies: 18
Views: 1359

Re: Wifi performance poor despite strong (-9) RSSI, how debug/diagnose?

That is why we shifted to using oscillators, since our products experience a wide temperature range. This one has a maximum error of 2ppm +-2ppm over temp range if I remember correctly.
by novalight
Thu May 17, 2018 6:36 am
Forum: Hardware
Topic: Wifi performance poor despite strong (-9) RSSI, how debug/diagnose?
Replies: 18
Views: 1359

Re: Wifi performance poor despite strong (-9) RSSI, how debug/diagnose?

It's not a crystal, it's an oscillator (thus no load caps, only one decoupling). I've verified this botch. The antenna here was hand assembled, the other units are machine assembled. Since I tested all units in the lab I am not sure if this could even be the issue (especially the oscillator thing, s...
by novalight
Thu May 17, 2018 6:11 am
Forum: Hardware
Topic: Wifi performance poor despite strong (-9) RSSI, how debug/diagnose?
Replies: 18
Views: 1359

Re: Wifi performance poor despite strong (-9) RSSI, how debug/diagnose?

It's to protect a bodge correcting swapped pins on the oscillator (40 MHz, 2ppm TCXO).
by novalight
Wed May 16, 2018 3:07 pm
Forum: Hardware
Topic: Wifi performance poor despite strong (-9) RSSI, how debug/diagnose?
Replies: 18
Views: 1359

Re: Wifi performance poor despite strong (-9) RSSI, how debug/diagnose?

Hi Angus, thanks for your reply! Sadly as the point of installation is very remote, testing various things (with case open, WROOM32, more distance) is not easy. This is why I was hoping for some remote testing possibilities. Regarding the RF-Cal: Since they calibrate the whole frontend and do (I thi...
by novalight
Mon May 14, 2018 9:04 pm
Forum: Hardware
Topic: Wifi performance poor despite strong (-9) RSSI, how debug/diagnose?
Replies: 18
Views: 1359

Re: Wifi performance poor despite strong (-9) RSSI, how debug/diagnose?

No idea on this? Is there anything more I can provide to help here? Are there other support channels in order to get deeper information/documentation about the RF calibration?
by novalight
Fri May 11, 2018 8:30 am
Forum: Hardware
Topic: Wifi performance poor despite strong (-9) RSSI, how debug/diagnose?
Replies: 18
Views: 1359

Re: Wifi performance poor despite strong (-9) RSSI, how debug/diagnose?

@fly135 that's what I notice on the other plants, only few ms of ping. Regarding the WiFi environment: most of the (identical software and hardware) devices are installed in shielded distribution boxes alongside with the WiFi router. This is also why the RSSI is very strong. There are now other WiFi...