ESP-01s vs Wemos D1 Mini

[Semper Talis]

I do not know if I am the only one with this problem , so please give feedback if you can.

I added the ESP-01s to the ALTAIR Duino and it seemed to work .

However I discovered quickly problems with unstable WiFi connections, slow response and breakdown of the connection after a few minutes.

First I blamed it on the weaker WiFi in my Office as my WiFi is optimized for the rest of the house but not my office.

But relocating the Altair closer to the WiFi router did not improve much and only very close proxy to the router made it stable.

As ESP-01s and the Wemos D1 Mini are practically the same , just that the Wemos has more accessible IO, I programmed a Wemos with the Serial2WiFi passthrough and replaced the ESP-01s .

The difference is breathtaking , no lag , rock solid connection even in my WiFi “hole” in my office 

Additionally more than one Telnet connection at a time is now possible.

I can Telnet in from my office computer and my laptop at the same time.

I checked the web for explanation and all I could find is that the ESP-01s has in deed a weaker antenna performance due to his small size .

It was also mentioned that the Wemos has a cleaner power supply wich may or may not improves the overall performance.

In summery here is what I did:

Replaced the ESP-01s with a Wemos D1 Mini loaded with the exact same Arduino sketch used for the ESp-01s.

The parts are naturally not incompatible , so either use wires to make the right connections or build a little adapter board.

Price difference is minimal , 

ESP-01s price ( $2.34 up to $9.79)

Wemos D1 Mini (~$3.41 or $2.17 in bulk) Sometimes you can snatch them for under $2

You can even get Wemos D1 with external antennas for even better reception.

Another advantage of the Wemos, it has a USB port included, so you need no programmer and can even change the software in place without disassembly of the Altair.

Also it has more memory and you can expand the capabilities by adding a HTTP server access and/or adding sensors, real time clock, etc .

[Semper Talis]

Correction I meant to say "pin compatible" not incompatible 

[Cliff Chism]

That’s all very interesting. I’ve got the esp01s sitting on my desk,waiting for time to install it. Maybe I’ll order the wemo to sit next to it for a while…lol. 

[Semper Talis]

Cliff,

well I am looking forward what your experience with the ESP-01s is .

If your WiFi router is in the same room you should not see much impact.

First thing I noticed when I moved away from the router was some lag/delay in the response from the Altair.

Then it would get a bit spotty and finally it just hang up on me.

But as I said , that is maybe just me , I had a very old ESP-01s laying around which I reused for this.

I think I got this almost a decade ago and played with it a little.

[Cliff Chism]

Ordered one this morning. I just dont know how long it will be before I get to install it. I teach my granddaughter a class on computers (now including computer history with the AltairDuino and IMSAI8080esp) and I decided that I wanted to show her how we communicated with BBS’s before the internet. But, i haven’t had a landline in over 10 years, so I started building a local PBX for the computers to connect to. Then, I had to set up a dos computer to run a bbs server and then we decided it would be cool if she had her own phone in her room to call her Papaw anytime she wanted to (she lives about a quarter mile away) so I am expanding the local pbx to her house using a wifi Halow link. It will also be interesting to see how high of a baud rate the Halow link will allow between modems at a quarter mile. The project has just ballooned. But, at the very least I should be able to look at the two boards and look for design differences that might influence wifi range before I actually install them. Be well. 

[Semper Talis]

That sounds to be a fun project .

Make sure she experience 300 baud :-) 

If I remember right I could get never higher than 1200 baud back then .

BTW, I was living In Germany in the late 80's and it was a real cost factor to call a BBS in the next town.( Calling local wasn't cheap either) 

I did it once and my mom got really angry with me when we got the phone bill.

I do not know how the situation was here in the US but even local BBS had a time limit when you called and you had to plan what you wanted to do otherwise you got disconnected in the middle of data transfer.

Beside all this , in Germany the telecom laws at the time where draconian .

You where not allowed to add anything to the phone line which was not brought via the German telecom.( Deutsche Bundespost) 

Not even an extension cable!.

Everyone with a computer and a modem where always on the lookout as the telecom where hawkish on checking that nobody touches "their" system.

It changed slowly in the 1990's but at the time it was ridiculous .

[Chris Davis]

Thanks for the info.  I will give the Wemos a try.  

I have not had an issue with my wifi connection with an ESP-01s but I guess I have a router just a few feet from my workbench.

[Semper Talis]

Just a note .

I have not further investigated but I have build a little adapter board for the Wemos D1 and plugged it in .

To my surprise I found it was also working spotty and had unstable connection.

I returned to my McGiver-wire solution which places the Wemos D1 about in the center of the Altair and it is back to a stable connection.

As said I have not investigated deeper into that .

I plan to do a wire setup for the ESP-01s to see if this is also showing improvements .

But this will take some days until I have the time to do that , I will send updates.

[Semper Talis]

So here is the update on what I found and I claim it only for my situation.

Totally unscientific I changed a couple of parameter and so I am not sure what had the most effect.

1) I improved my reception of the WiFi in my office by slightly rearranging the Routers position in the dedicated server closet  at the far end of my home.

    This improved the reception of the ESP-01s and I got rid of the lag and sometimes disconnects

2) I crosschecked with the Weimos D1 mounted on a little PCB so it fits on the socket of the ALTAIR and it get better reception than the ESP-01s but not much 

3) Then I did a fall back with wire extensions and relocating the Wemos D1 as well cross checking with a relocated ESP-01s that this makes more improvements.

    With the relocation of the Modules I can now do XMODEM Assembler files back and forth but larger files like whole disk images will cause Errors.

So Bottom line the real problem I had was the bad reception of my Home WiFi in my office , improving that has improved the WiFi situation for the Altair a lot.

I can see that the original Location of the WiFI module in the ALTAIR has some trouble compared to relocating the module away from beneath the VT100 board.

Also the Demos D1 , most likely because of the larger antenna and some improved PCB layout , will give better WiFi reception .

In my case I do not connect the WiFi to the TX/RX pins of the Arduino Due , I use the D18/D19 of the VT100 card and have it removed now completely from the Altair.

This has for me given the same performance as the relocation of the module.

Actually the gain from Demos D1 is now so minimal that I keep the ESP-01s as WiFi installed.

Hope these findings do help someone in a similar situation.