New Lolin D32 Pro with 4MB PSRAM

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Dave_Abq
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Joined: Wed Jul 19, 2017 10:42 pm

Re: New Lolin D32 Pro with 4MB PSRAM

Post by Dave_Abq » Tue Jul 03, 2018 5:46 pm

Has anyone successfully reloaded firmware into the new Lolin D32 Pro? Which firmware is compatible? I have tried a variety, they seem to load successfully with esptool, but then I keep getting the 'flash read error, 1000.'

kevinkk525
Posts: 525
Joined: Sat Feb 03, 2018 7:02 pm

Re: New Lolin D32 Pro with 4MB PSRAM

Post by kevinkk525 » Tue Jul 03, 2018 5:58 pm

Does it work except for that error message?
I get that error message on my old lolin esp32 pro board with loboris port but it works anyway (but it's not as stable as my other esp32).
Kevin Köck
Micropython Smarthome Firmware: https://github.com/kevinkk525/pysmartnode

Dave_Abq
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Joined: Wed Jul 19, 2017 10:42 pm

Re: New Lolin D32 Pro with 4MB PSRAM

Post by Dave_Abq » Wed Jul 04, 2018 1:32 pm

Kevin
The board does not 'work' in the sense that I cannot get to a REPL. On bootup after flashing the new binary, I enter a boot loop with:

rst:0x10 (RTCWDT_RTC_RESET),boot:0x37 (SPI_FAST_FLASH_BOOT)
flash read err, 1000
ets_main.c 371
ets Jun 8 2016 00:22:57

repeatedly.

Dave

kevinkk525
Posts: 525
Joined: Sat Feb 03, 2018 7:02 pm

Re: New Lolin D32 Pro with 4MB PSRAM

Post by kevinkk525 » Wed Jul 04, 2018 5:34 pm

That's weird. Did you flash the official firmware or loboris port? If you flashed his port, you should ask on his forum as he is more likely to see the message there.
Kevin Köck
Micropython Smarthome Firmware: https://github.com/kevinkk525/pysmartnode

OutoftheBOTS_
Posts: 678
Joined: Mon Nov 20, 2017 10:18 am

Re: New Lolin D32 Pro with 4MB PSRAM

Post by OutoftheBOTS_ » Wed Jul 04, 2018 9:35 pm

I have not seen the schematic of the dev board but many of these dev boards are being made without the 100nf cap on the EN line as per espressif datasheet and this has been known to caused this problem you having. Can you check to see if there is a cap on the EN line.

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mcauser
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Re: New Lolin D32 Pro with 4MB PSRAM

Post by mcauser » Wed Jul 04, 2018 9:43 pm

https://wiki.wemos.cc/_media/products:d ... v2.0.0.pdf
EN has a 10K pull up to 3v3, switch to gnd and 100nF to gnd.

Dave_Abq
Posts: 6
Joined: Wed Jul 19, 2017 10:42 pm

Re: New Lolin D32 Pro with 4MB PSRAM

Post by Dave_Abq » Thu Jul 05, 2018 5:36 pm

kevinkk525 wrote:
Wed Jul 04, 2018 5:34 pm
That's weird. Did you flash the official firmware or loboris port? If you flashed his port, you should ask on his forum as he is more likely to see the message there.
Kevin, I flashed the Loboris port originally and got this boot loop behavior with several variants of the Loboris software loads. I then moved to Damien's latest firmware on the micropython site, and got exactly the same boot loop behavior. I have tried to contact Wemos through the AliExpress order dialog, but I am not getting a response from them, not sure if anyone knows a more direct way to reach their tech support.

Its hard to inspect the hardware with all very tiny surface mount components, but thanks to mcauser, the literature/ schematic from wemos seems to show the appropriate capacitor.

I have a second board, which is still working fine with the micropython they loaded, but I am reluctant to experiment with a new firmware load on the second board since it may have the same quirk.

kevinkk525
Posts: 525
Joined: Sat Feb 03, 2018 7:02 pm

Re: New Lolin D32 Pro with 4MB PSRAM

Post by kevinkk525 » Fri Jul 06, 2018 8:24 am

Better experiment with the 2nd board too if it's the same. Only then you'll know for sure if one unit is faulty or both.
Kevin Köck
Micropython Smarthome Firmware: https://github.com/kevinkk525/pysmartnode

Dave_Abq
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Joined: Wed Jul 19, 2017 10:42 pm

Re: New Lolin D32 Pro with 4MB PSRAM

Post by Dave_Abq » Sat Jul 07, 2018 3:20 pm

So just a heads up for those considering this board.

Ali-Express refunded my entire purchase price plus shipping for the two boards, never any technical response from Lolin. I did in my filing, link to this post sequence here on the Micropython forum, so Lolin would be able to duplicate just what I have discussed here.

Read into that what you wish, I think I will wait weeks or months before I try their boards again, in case they are resolving a technical shortfall/ discrepancy. I am interested if anyone else manages to load new firmware into the D32 Pro.

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Roberthh
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Location: Rhineland, Europe

Re: New Lolin D32 Pro with 4MB PSRAM

Post by Roberthh » Sat Jul 07, 2018 7:10 pm

I have a few WEMOS LoLin32 from the old series including two PRO models (4 MB RAM/Flash). One of them is working fine with all variants of ESP32 micropython. The other works fair. When using the Pycom WiPy image, it boots and freezes after a few seconds. The Micropython.org firmware and the pre-packaged lobiris firmware work fine. The Wemos device w/o SPIRAM work fine all the time. I upgraded one of them with SPIRAM (just for interest, not for the need), and that is stable too.

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