WEMOS ESP8266 D1 mini

[Turgut Guneysu]

Hi There,

So I wanted to experiment with my ESP8266 Wemos D1 mini.

Successfully flashed it with pytools. Hooked it up and got microBlocks to connect to it, and flashed the USERLED on & off.

Then I wanted to try some of the WEBThings blocks.

I optioned the Create a Hotspot block with SSID: myWEMOS and PW: abcdef

WEMOS LED kept blinking ON/OFF with 500ms delay.

After a long while (4 minutes), I received a message that said my IP was: 169.254.201.253.

Cool! So I did a scan on my phone and the PC, looking for myWEMOS SSID. Could not detect anything like it !

Now what?

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RELATED:

I also have a NODEMCU v3 8266MOD card. I can also flash it successfully. However, when I connect to USB and start microBlocks, I get a streaming sequence of errors on the command.com window. Something like this:

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SDL2 headers: 2.0.7; lib: 2.0.7Bad message start byte; should be 250 or 251 but is: 10

Exception (29):epc1=0x4000e1b2 epc2=0x00000000 epc3=0x00000000 excvaddr=0x00000000 depc=0x00000000

ctx: contsp: 3ffffc70 end: 3fffffc0 offset: 01a03ffffe10:  3ffffe50 00000000 3fffbdf4 000000003ffffe20:  000000a0 00000000 00000578 0000Bad message start byte; should be 250 or 251 but is: 4805783ffffe30:  000000f0 3fffbBad message start byte; should be 250 or 251 but is: 98be4 3fffbbdc 4020cb613ffffe40Bad message start byte; should be 250 or 251 but is: 58:  00000578 402148a8 feefeffe feBad message start byte; should be 250 or 251 but is: 101efeffe3ffffe50:  4020c234 4020c218 4020c1fc 000fa0003ffffe60:  00300000 00001000 00002000 000001003ffffe70:  00000200 00000fa0 feefeffe feefeffe3ffffe80:  feefeffe feefeffe feefeffe 3fff900c3ffffe90:  3fff35e0 3fffbbe4 3fffbbdc 4020cbaa3ffffea0:  feefeffe 00005000 3fff9260 402146c13ffffeb0:  3fffdad0 3ffe9c64 00000017 4020769b3ffffec0:  6c655702 656d6f63 206f7420 7263694d3ffffed0:  6f6cBad message start byte; should be 250 or 251 but is: 52426f 21736b63 feefeffe feefeffe3ffffee0:  feefeffe feefeffe feefeffe 000001003ffffef0:  00000013 00000000 3fffa24c 4020486Bad message start byte; should be 250 or 251 but is: 5353fffff00:  4020d221 feefeffe feefeffe feefeffe3fffff10:  4020d505 3fffbcd4 3fffbcbc 4020dBad message start byte; should be 250 or 251 but is: 535273fffff20:  0000001c 0001c2Bad message start byte; should be 250 or 251 but is: 4800 00000000 000000003fffff30:  00000003 4020d6e9 ffffffff 000000013fffff40:  feefeffe 0000Bad message start byte; should be 250 or 251 but is: 480001 3fff8f8c 3fff900c3fffff5Bad message start byte; should be 250 or 251 but is: 480:  00000000 00000001 3fff8f8c 4020a2f03fffff60:  00000000 feefeffe feefeffe feefeffe3ffffBad message start byte; should be 250 or 251 but is: 102f70:  0001c200 00000000 3fff8fccBad message start byte; should be 250 or 251 but is: 324020a8003fffff80:  3fffdad0Bad message start byte; should be 250 or 251 but is: 4800000000 3fff8fcc 3fff900c3fffff90:  3fffdad0 00000000 3fff8fBad message start byte; should be 250 or 251 but is: 99cc 40207b003fffffa0:  feefeffBad message start byte; should be 250 or 251 but is: 101e feefeffe feefeffe 4020ae143fffffb0:  feefeffe feefeffe 3ffe8584 401012e5<<<stack<<<

lasBad message start byte; should be 250 or 251 but is: 116t failed alloc call: 4020CB39(1400)

Bad message start byte; should be 250 or 251 but is: 13

ets Jan  8 2013,rst cause:2, boot mode:(3,0)

load 0x4010f000, len 1384, room 16tail 8

Bad message start byte; should be 250 or 251 but is: 99chksum 0x2dcsum 0x2dvbc204a9b~ld

Bad message start byte; should be 250 or 251 but is: 10

Exception (29):epc1=0x4000e1b2 epc2=0x00000000 epc3=0x00000000 excvaddr=0x00000000 depc=0x0000

This is only an extract since the scrolling is so rapid, it is impossible to capture everything.

Board LED keeps blinking at the speed of the command window display scroll.

If I press RESET, the command window closes down, but the LED keeps on blinking.

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[John Maloney]

I’ve seen a number of postings about power supply/regulation issues with Wemos D1 mini. One solution seems to be to use a power source with lots of current. Another fix seems to be to add a fairly large capacitor across the power supply pins on the board.

WiFi uses a lot of current (in bursts), which would explain why a simple “blink” that doesn’t use WiFi works but WiFi doesn’t (or makes it unreliable).

Another user has reported that that, while most of her many Wemos D1 boards work, two of them fail. The terminal output she sees at startup time is consistent with insufficient power.

If you want to see what’s going on, make sure that MicroBlocks is not running, then start up a terminal program set to 115200 baud and connect to to the D1’s COM port. Press the reset button on the D1. You should see some messages as it starts up. If you see a repeated sequence of restarts, it’s failing at startup time. The strings “ets Jan 8 2013,rst cause:4, boot mode:(3,7)” (a low-power reset) or “wdt reset” (watch dog timer reset) are symptoms of power supply issues.

Those Wemos boards are inexpensive, but it sounds as though they are not be reliable. I’ve had good luck with my Amica NodeMCU board:

https://www.amazon.com/HiLetgo-Internet-Development-Wireless-Micropython/dp/B081CSJV2V/ref=sr_1_2?keywords=nodemcu+hiletgo&qid=1579622253&sr=8-2

Regarding your NODEMCU v3 8266MOD:

It is rebooting itself over and over, I’m not sure why. Make sure you’re installing the latest version of MicroBlocks VM from:

http://microblocks.fun/additional_downloads

Good luck!

[John Maloney]

You might wait for v0.3.4 and try installing that version of the ESP8266 MicroBlocks VM on your NODEMCU v3 8266MOD. That release includes a fix that make the VM work better on the Wemos D1 mini and it might also help on other ESP8266 boards. Let us know if it works…

[Bernat Romagosa]

No need to wait anymore. I’ve just released 0.3.4

[Turgut Guneysu]

See Issues #91 and #92.

[John Maloney]

Do those two issues replace this one?

[Turgut Guneysu]

My last comment for this set:

I tested both ESP8266 and WEMOSD1mini with the latest 3.6.

• In IDE firmware update still gives ESPTOOL error - manual works with the latest ESPTOOL version.

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• Both devices come online without a problem, can disconnect and connect without a problem.
  However, if the RESET button is pressed, the command window displays a few error messages, and disappears completely. This also happened in the previous release 3.5. Before then, it was not loading correctly.

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[John Maloney]

Thanks! The out-of-date esptool issue is reported in #92.

Seeing error messages when you hit “reset” is normal for ESP boards; they are the result of the ESP’s operating system printing some startup information that doesn’t conform to the MicroBlocks IDE’s serial protocol. The IDE usually just prints warnings and skips over that data.

But console window going away when you hit “reset” is odd. Does that kill the MicroBlocks IDE window, too?

If you get a moment, it would be worth starting a new issue for that one. I’ve never seen that happen so it may be specific to Windows.

[John Maloney]

Updated the version of esptool.exe built into MicroBlocks to use Python 3.