May 27, 2024, 02:58:37 PM

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ESP32 / ESP32 poe noise
Last post by korneo - May 10, 2024, 03:32:08 PM
Hello everyone,

i have a ESP32-POE2 board and I am reading an potentiometer (0-3.3V) value, however there is a(200KHz) ripple on all voltage rails which is not desirable for accurate measurements.

i have already added an 10nF capacitor close to the input, and a bigger one, which does not help unfortunately.

this significant ripple only appears when the poe power supply is connected(HP1820 J9982A), on usb it works fine and all voltage rails are stable(no 200KHz noise)

does anyone know how i can get rid of the ripple and can obtain a stable adc readout?

thanks in advance

A20 / Re: LIME2 Rev.L lock-up freeze...
Last post by LubOlimex - May 10, 2024, 08:14:47 AM
But what does it say at start of boot over the serial? It is important that the revision is properly listed as revision L. Often people would delete the contents of the EEPROM (thus disabling automatic board recognition by the Olimage) and then also fail to manually configure the board via the u-boot-tools and then the board would load some generic revision A preset that might have settings incompatible with the actual board revision used. Like RAM timings, different LAN controller and so.
A20 / Re: LIME2 Rev.L lock-up freeze...
Last post by mbosschaert - May 09, 2024, 10:29:18 PM
Quote from: LubOlimex on May 09, 2024, 02:48:31 PMCPU:   Allwinner A20 (SUN7I)
ID:    A20-OLinuXino-LIME2 Rev.L

It identifies like this:
CPU: ARMv7 Processor [410fc074] revision 4 (ARMv7), cr=10c5387d
OF: fdt: Machine model: Olimex A20-OLinuXino-LIME2

I'm running an up to date olimex debian bullseye
A20 / Re: LIME2 Rev.L lock-up freeze...
Last post by LubOlimex - May 09, 2024, 02:48:31 PM
Compare the BOMs (Bill-Of-Materials) to confirm what is the part. But I doubt change in MCP120T475I-TT to MCP121T475I-TT can be any sort of issue.

Improper timings for the RAM memory are more likely. Are the boards and revisions properly listed at start of boot process? Like does it say:

CPU:   Allwinner A20 (SUN7I)
ID:    A20-OLinuXino-LIME2 Rev.L
ESP32 / Re: ESP32-POE: esp_eth_driver_...
Last post by DirkB19 - May 09, 2024, 02:43:29 PM

Thanks for the support, now it works.
I was getting a little desperate  ;D
Because first I overlooked your tip to enable PSRAM ... this is definitely needed to make it work.
I would document this in Wiki or Documentation for other noobs like me who will encounter this.
A20 / Re: LIME2 Rev.L lock-up freeze...
Last post by mbosschaert - May 08, 2024, 11:08:14 PM
I'm also still having these freezes with all of my Rev.L boards when a SATA HD (Or SSD) is connected, this is irrespective of the Olimex-debian version, the power supply, lipo connected, etc.

From this conversation I understand that Rev.K2 used to be stable with this respect.

Most important changes to consequtive versions of the board concern RAM, eMMC and the power supervisors. As I'm not using EMMC, and the suggestion that it is a power-handling problem make me consider to replace the power-supervisor component back to the one which is used in Rev.K2. Reading the revision document however confuses me a bit. On line 201 (Rev.K1) is stated that MCP121T475I-TT is used, however on line 215 (Rev.L) is stated that U14 is changed from MCP120T475I-TT to MCP121T475I-TT. The latter suggests that Rev.K1 has MCP120T475I-TT on U14. Or did I miss something here?

@LubOlimex, could you confirm this?

As around U14 there is sufficient space on the board I think exchanging this component should be possible.

Does this sound as test worthwile or is the idea not realistic or completely insane... ?
A64 / Re: Bookworm upgrade availabil...
Last post by mbosschaert - May 08, 2024, 01:34:41 PM
As for whom it may be relevant, now, halve a year after installing bookworm from scratch on a lime2 board, is is still rock-solid. Even better, homeassistant-supervised is stable and the regular updates install without any issues. If someone is interesed in the installation process for homeassistant, just drop me a personal message
ESP32 / Re: ESP32-POE: esp_eth_driver_...
Last post by LubOlimex - May 08, 2024, 10:20:08 AM
I use latest ESP32 package which appears to be version 3.0.0-rc1. Changed the defines of default example at start to:

// Important to be defined BEFORE including ETH.h for ETH.begin() to work.
// Example RMII LAN8720 (Olimex, etc.)
#ifndef ETH_PHY_TYPE
#define ETH_PHY_TYPE        ETH_PHY_LAN8720
#define ETH_PHY_ADDR        0
#define ETH_PHY_MDC        23
#define ETH_PHY_MDIO        18
#define ETH_PHY_POWER      12

Also reduced delay at end to 1000:

void loop()
  if (eth_connected) {
    testClient("", 80);

The board I selected is "Olimex ESP32-POE" and then changed PSRAM to enabled. Uploaded and it seems to work fine.
AVR / Re: AVR-ISP MK2 Failed to get ...
Last post by LubOlimex - May 08, 2024, 08:12:50 AM
It should be some sort of driver issue. libusb-win32 is fine as I've tested previously.

It feels like this same problem:
ESP32 / Re: ESP32-POE: esp_eth_driver_...
Last post by LubOlimex - May 08, 2024, 08:09:56 AM
I will test it again later today and if it works here I will give you instructions on what I use and what I did.

It is important to notice each ESP32-POE2 is tested empirically and the Ethernet is part of the test. Even if there is a problem it is not related to the hardware.

Edit: I found the issue - the board comes with ESP32-WROVER-E module. The information everywhere says it comes with WROOM but upon checking empirically the product it comes with ESP32-WROVER-E-N4R8. This causes two pin difference since WROVER module has PSRAM (and the PSRAM requires two pins extra). This is visible in the schematic top left corner of Ethernet box - now eMAC clock is GPIO0, not GPIO17.