Espress for HeaterMeter Module (wifi with no Pi/Linkmeter needed)



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Hey, that's great that you got it working!!

> about software serial...yes, I use the latest version of it and it seems to fix 'old' issues I've found. So you can use the latest versions of all items...

> as far as the (max,min)..etc, that's just an html thing, the inputs are there in the espressHM html files (you get all the same setup/functionality setup), they are just not just visually appealing (yet :) )

> the mqtt is a great thing in the iOT world....let me know if/when you get that working! I've only use thingspeak for now...

>I've updated the github html folder with a 'sample' of local page I use for debugging....but it works. You could make it a lot 'nicer' looking, but it shows the basic functionality.

>The Espress has a few urls to get a json for curinfo. xx.xx.xx.xx/hm/curinfo will get you the json of current data. You can also set it (don't know off the top of my head)...but if you look at the html you can see the url it uses to remotely setup...

>as far as mobile apps....the dashboard works on the mobile ok through thingspeak, (you get info and can set temp)....I use it with no issues.....

Let me know how it works out for you....I think you're user #2 or #3.....



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Thanks for adding localhm.html to github. With that I was able to modify the format of the JSON data in the sendHMJsonweb function in globals.cpp to match (some of) the JSON data returned from "/luci/lm/hmstatus" on the raspPi HM (described here: Note, I have also changed "/hm/curinfo" to "/luci/lm/hmstatus". This allows apps that rely on this data to work without any changes to the app (I have the PebbleHM watch app updating properly when connected to the Espress HM). The PitDroid app doesn't seem to work, but I'm not sure how it is getting HM data.

I have also made some changes so that the probe names and alarm limits entered on the Probe Config web page are reflected in the JSON data and on the localhm.html page. I also added a button to link to the localhm.html page from the main HM web page. We may want to update the ThingSpeak and MQTT stuff so these modified probe names (and maybe limits) are sent. Currently ThingSpeak just displays default probe names ("Pit", "Food1", "Food2", etc), but maybe it is possible to update these names dynamically. I was thinking of modifying the MQTT publish status messages so it just sends one message with the hmstatus JSON data, but this also adds some parsing complexity on the receive side... so I didn't change anything yet.

Note, I have not tested this yet, but I think the "if (!MyWebServer.isAuthorized()) return;" check at the beginning of the sendHMJsonweb() function should be removed, since this link only returns status. I believe this is how it is implemented on the raspPi HM (no auth required for hmstatus).

Can you PM me your email so I can send you my code changes to review (and hopefully add to github)?

Some other observations:
- There was drop down box on the probe config web page to enable or disable a probe, but I don't think it was used anywhere yet so I removed it for now. I also added some text to the probe config web page to explain how to set TRM to disable a probe or use "Internal" vs "Thermocouple".

- I am fairly frequently (maybe every half hour) experiencing issues connecting to the web browser and the only way to correct the issue is to power cycle the heatermeter. This seems to be related to having multiple clients (phone and laptop) connected to the esp webserver, but I really don't know. Note, this also seems to be brought on by going back and forth between the different web config pages... because I have let it run overnight and have been able to reconnect the next day with no issues.

- Probe3 alarm ringing ("r") JSON data doesn't seem to be updating properly. I think this is an issue with either parsing the serial data in GlobalsClass::checkSerialMsg() or maybe the serial message isn't even getting sent for Probe3. I'll try a test to see if this works correctly when using my raspPi HM setup.



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Espress v1.0 NOW RELEASED!!!!

I'm happy to release a version for anyone to try out today... Download the Espress for HeaterMeter Software here.

Read the include PDF on how to setup your Module to work with HeaterMeter.

Features include:

Super Easy to configure! You simply use your phone/tablet to connect to the access point of the module to setup internet/cloud connections.

Works with internet cloud services (thingspeak & mqtt). You do NOT require any port forwarding or open ports on your router for it to work from the outside.

MQTT support allows it to work with many existing home automation systems....

The Espress Module supports firmware updating of itself and of the attached HM. (HM requires optiboot bootloader)

Remote Pit Temp/Alarms setting and support. Took me just a couple of minutes to setup thingspeak to send me an alarm through twitter!

Super Value! Yes you can get a decent nodemcu board for under $5 shipped for ebay/ali! Also because it's all flash based SOC, it starts up and connects within seconds!

Thanks for Charles/Will for helping me test out the's still in try it out and let me know how it works for you!

I've also worked on an 'improved' dashboard (just started playing with bootstrap): Try the link here (it's a demo account so you can play around)..... try dashboard

Hi David,
I am maybe a little late, but I think my Pi is busted and I tried to find a solution.
I have a ESP board similar to Your pictures, and It seems to flash from my PC.
I can find it under networks but the ESP name comes up as AI-Thinker. so I presume it is not correctly flashed.( how can I check if the flash size is 4MB)

But I see in Your "Configure of Espress for HeaterMeter: .pdf" ;
STEP #1 Get the Espress Module(ESP) to connect to your internet router.

Do i have to connect to the Internet router ? I am now connected via USB to the PC.
Sorry for the maybe dumb questions, but I hope I can get it working.


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Hi FredB, For the latest install instructions and files, download this file.

the zip has the esp8266 flasher for windows, that will help you flash the bin and I believe will also tell you the size of the flash....

if you have any questions after reading the pdf within that zip, you can email me at david @