ESP32 based IoT gateway/control hub with TFT, touch, RFM69 and more..

[NW27]

Hi Martin,
I've placed an order for one of your TFT32 units.
I want to use this as a MQTT gateway to mysensor devices. It would be great if the gateway supported the MQTT auto discovery protocol (homie 3 ) https://homieiot.github.io/
It would be good if the tft32 showed the incoming/outgoing messages on the screen.

Now i need some 915Mhz mysensor boards. I currently have no mysensor equipment.
I'm looking for PIR movement, temp/humidity, door/window.
Any suggestions on units?

Thanks,
Neil.

[Martin Harizanov]

@nw27 said in ESP32 based IoT gateway/control hub with TFT, touch, RFM69 and more..:

MQTT auto discovery protocol (homie 3 )

The "homie convention" sounds interesting. I will take a look, I think standardization on this subject is long overdue.

RE: It would be good if the tft32 showed the incoming/outgoing messages on the screen.

That would, of course, be possible, with some modifications to the firmware. What would be more interesting, in my view, is to discover the type of message and visualize accordingly i.e. temperatures as a gauge, switches as a toggle switch etc. based on the "homie convention". Such software will require significant effort

RE: Now i need some 915Mhz mysensor boards. I currently have no mysensor equipment. I'm looking for PIR movement, temp/humidity, door/window.

TFT32 has a 433Mhz RFM69HW , and you mention 915Mhz. These won't be compatible. I also offer TFT32 without RFM69HW, so you can buy your own 915Mhz version and solder it.

In general, you need battery operated nodes with 433Mhz RFM69s to be compatible with TFT32's RFM69HW@433Mhz, google for Moteino, but I believe there are RFM69 powered mysensor nodes as well.

[scalz]

looks nice :)
your device could perhaps be better (radio performance) if there was nothing around and behind antennas, especially for a gw.
I prefer webapp vs TFT, as it offers more design freedom and I'm often closer to my phone than to my devices like the gw.
But I agree it can be useful in some others usecases.

[Martin Harizanov]

@scalz said in ESP32 based IoT gateway/control hub with TFT, touch, RFM69 and more..:

) if there was nothing around and behind antennas, especially for a gw.
I prefer webapp vs TFT, as it offers more design freedom and I'm often closer to my phone than to my devices like the gw.
But I agree it can be useful in some others usecases.

My issues with using my phone to access IoT devices at home are:

• I can't control any of the devices at home when no internet connection is available (in a cloud IoT setup)
• Guests/family members can't control room thermostats without access to my phone
• It is a cost reduction by centralizing controls and simplifying actuators
• independent from smart devices, I prefer to leave my phone away from my bedroom
• The TFT32 can be used as an always-on reference, just look at it and you have all the information you need instead of checking it on the phone

So basically this is why I needed this sort of a control hub.

Regarding the RF interference, it actually works very well even so. For the future, I plan to have an external RF antenna option for the RFM69 and flip the WiFi sideways to where the buttons are. I'll probably get rid of the buttons as I don't use them.

[NW27]

@martin-harizanov
Hi Martin,
For the unit that I have ordered, could you please supply it with the minimal soldered connections on the RFM69 unit so that I can easily change it over for a 915Mhz version.
I also not that you are saying RFM69HW as opposed to RFM69HCW as per the Moteino you suggested looking at.

I was just going for the 915 because there appears to be significantly more consumer (retail) equipment on the 433MHz, including my current X10 equipment.
I had also been told that 915MHz got in and around buildings better than 433 due to things like house wall frame spacing.
Thanks,
Neil.

[Martin Harizanov]

@nw27 said in ESP32 based IoT gateway/control hub with TFT, touch, RFM69 and more..:

RFM69HW as opposed to RFM69HCW as

I mailed you a version with the RFM69HW unsoldered.

RFM69, RFM69HW, RFM69HCW, and RFM69CW can all talk to each other; the 'H' indicates the 'high power' version and the 'CW' - compatible pinout i.e. smaller package. The CW version was more difficult to source at the time, so I decided to use the regular RFM69s. You can source 915Mhz RFM69 here.

[Nca78]

Hi Martin, just a question regarding the touch screen after looking at the schematics, I'm curious about why you didn't use an XPT2046 for that ? As it costs nearly nothing, saves I/O pins and makes code a bit easier and possibly more reactive if you use interrupt, it's the ic that's used on the "pcb" version of the lcd.

[Martin Harizanov]

@nca78 said in ESP32 based IoT gateway/control hub with TFT, touch, RFM69 and more..:

XPT2046

I don't use the XPT2046 or any external ICs , the ESP32 handles it. This approach "costs" 4 pins, but I wanted to keep the BOM smaller. Also, I had concerns about sharing the HSPI with XPT2046, as I use DMA and double video buffer in my projects, I wasn't sure that would work well. The VSPI is dedicated for RFM69, maybe it can be shared with XPT2046 without issues. I guess this is something to experiment with in the following PCB revision

[Nca78]

@martin-harizanov I had no problem with shared HSPI for both lcd and touch sensor. I use Bodmer TFT eSPI (it manages both lcd and xpt2046 for touch) and it's impressively fast. I have shared with SD card too, and still no problem.
https://github.com/Bodmer/TFT_eSPI
But you will not save 4 i/o as you need at least a chip select for touch, and maybe interrupt pin.

[Martin Harizanov]

@nca78 said in ESP32 based IoT gateway/control hub with TFT, touch, RFM69 and more..:

Bodmer TFT eSPI

Bodmer TFT eSPI is just a normal SPI driver, well maybe optimized a bit. The key to speed (IMHO) is to use double frame buffer and DMA for the SPI, that leaves the CPU free to process the next frame while the hardware does the SPI transfer. I am not aware of such TFT library for Arduino.