Davis Vantage Rainmeter and ESP32 - Solved ghost interrupt

[benp]

This is an update of my Davis+FGBS222 zwave configuration on the french forum:
https://easydomoticz.com/forum/viewtopic.php?t=13278
I have no question because my project is supposed to be fully functional according to my test "water in the boottle" but only true rain will tell me...
Comments are welcome!

I thought I had a problem with zwave so I did the migration from zwave to ESP32 but in fact the rainmeter was dirty. I just clean it...

Anyway: I was not very happy with the zwave solution because data received in domoticz were not very clean so I had to clean it inside domoticz: data from the reed switch are sometime received in the bad order so I had to filter, FGBS is sometime on a bad state on switch on... I had to filter all that in the dz vents script...

Before the Davis rainmeter, I tried other solutions:

• 433 MHz Oregon PCR800: not so bad but last only one or 2 years and not anymore manufactured
• Zwave Popp Z-Rain: not reliable for 80€ : values are sometime eratic. https://www.domoticz.com/forum/viewtopic.php?t=36292
• 433 Mhz TFA 30.3233.01 +RFXcom : not really better but only 27€

Warning: always use a manual rainmeter to know if your values are valid or not!

Materials:

• Davis 6464M rainmeter: 149€
• RJ11 Breakout BOB-14021 at sparkfun $2.10
• RJ11 6-Pin Connector PRT-00132 at sparkfun $1.50
• ESP32 DFR0478 at DFRobot (any other ESP32 should work): $8.90
• Micro USB power supply

Why such an expensive rainmeter: because this is the only reliable rainmeter according to the members of infoclimat forum.
The rainmeter is a part of the vantage pro 2 weather station at more than 1000€ not including ethernet gateways annual service charge...

Wiring:
Connect 4 & 5 from RJ11 to GND and IO25/D2 of ESP32: wire can be reversed because connected to the reed switch inside the rainmeter

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Note: ESP32 and RJ11 are inside house and rainmeter outside

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RJ11 connection between rainmeter and ESP32

To do in domoticz:
Add a rainmeter and an alert as virtual devices. Look at the idx: rainmeter is 100 and alert 101 in my arduino program

Install arduino and the firebeetle board according to the dfrobot tutorials:
https://www.dfrobot.com/blog-1578.html

The arduino program:
Before you use and try to understand this program, things you must know:

• The rainmeter is not easy to de-bounce because the reed switch is only closed from 119ms to 141 ms
• Interrupt are used because http connection can last more than 150ms
• ESP32 is a 2 core microcontroller with multitask capabilities. Conflict are possible when you try to read/write the same variable in interrupt/main process. portENTER_CRITICAL_ISR(&mux); must be used
• You must change ssid + password + IP address + port + idx in my program
• The program autoreconnect on disconnect
• The alarm log reconnect and http error (once reliable communication is back)
• There is too much alert because the program is in test waiting for the next rain this night according to the forecast...
• Nothing to do in domoticz because eveything is done with Domoticz API/JSON URL

The code is 225 lines against 45 lines for the zwave version...

[Update 23/04/2024] the new code with no ghost interrupt is in the Arduino forum:
https://forum.arduino.cc/t/stange-ghost ... /1250942/3

[benp]

Bad new: the ESP32 detect false rainmeter bucket
The TFA

tfaR.png (6.4 KiB) Viewed 823 times

The ESP32

davis3R.png (4.13 KiB) Viewed 823 times

Maybe the pullup resistor is too high: around 50kohms according to ESP32 users. The wire to the rainmeter is 15 meters long.
I tried to add a 1000 ohms resistor as pullup.

IMG_20240420_111112bd.jpg (67.99 KiB) Viewed 823 times

But no luck: I had 3 false bucket during this post writing (10 minutes).

[mgugu]

This may be an electromagnetic interference problem (15 meters is a lot), several checks possible:
- Shorter wire
- Shielded wire
- Use 2 pull up inside and outside
- Small capacitor at the reception (47 pf)
- Optocouplers
- ...
But definitely it is not a Domoticz problem but an electronic one

[benp]

This may be an electromagnetic interference problem (15 meters is a lot), several checks possible:

Thank you. I simplified the wiring: nothing plugged to the ESP32. Only the INPUT_PULLUP: I still have the problem: the interrupt fire 3 times per hour up to one time per 8 hours.

But definitely it is not a Domoticz problem but an electronic one

According to this experiment: that's not a Domoticz problem neither an electronic problem but an Arduino/ESP32 problem.
I will post to the Arduino forum: link coming soon here.

[benp]

Here is the link to the arduino forum:
https://forum.arduino.cc/t/stange-ghost ... cz/1250942

[benp]

The link to the Arduino forum:
https://forum.arduino.cc/t/stange-ghost ... cz/1250942

The ghost interrupt problem is SOLVED: this is an ESP32 bug.

Ghost interrupt can occur with wifi sleep so wifi sleep must be disable!
I will update the first post with link to working code.