Hii i just wanted to ask for advice before i start spending hours on coding this little project.
I want to build my own indoor temperature/humidity and air pressure station but using two Arduino boards since i want to use my 2.8" TFT LCD shield display for the readings. Ive wired the boards together and the sensors I'm using are from the Arduino Sensor Kit
This is what Ive managed to do so far and wanted to make sure i'm on the right page or not? ;-; I realized it would be easier to do on a breadboard but already came this far, any advise?
ps: i'm VERY new to stuff like this as you may see from the photo, sorry!! :"")
My advice: avoid using two Arduinos. Usually that makes the whole project significantly more difficult. The fact that you are using a shield display isn't a good enough reason to use two Arduinos. There will be other solutions.
That's how i kinda feel with it ngl! ;-;... would wiring it all with two sensors be better? can it handle both? if so what's my limit here? Thank you so much for replyingg!!!
Those shields use every pin except D0, D1 and A5. D10-D13 (SPI) are possible to use if you're not using the uSD slot. Which you really shouldn't do anyhow if the shield is hooked up to a 5V board because there's no level translation on the SPI lines, just the display.
I would never buy one of those. Now, I would never buy one even more!
@cometboyxx6 my other advice: buy a better display. But check it with the forum before you do. There are many such products that are sold only to inexperienced beginners.
They're not without their good points. They can be faster to update than a SPI attached display. And, umm... lemme think... I'm sure there were other things... nope, can't think of anything else just now.
Okay, "their good point", singular!
If you're putting a RPi Pico on a PCB and bringing out a bunch of I/O lines in the Uno headers' footprint, they're not bad. They run fine with 3.3V I/O, and the uSD slot becomes usable long term. And you still end up with 8 I/O lines free on the Pico, including I2C, serial and an ADC.
But that's a pretty niche case. On an actual Uno... if you want to hook up anything other than the display at the same time, they wouldn't be my first choice. Or second.
If you still want to use the the two board set-up, I would connect the serial port from the TFT Uno to pins 2 and 3 on the Sensor Uno. Using 0 and 1 can interfere with uploading sketches. So now you use Software serial on the Sensor Uno to talk with the TFT Uno and can still do Serial prints for displaying data on your PC/laptop.
you could look at a CYD dislpay
such displays have so much functionality on board that external IOs are limited
However, the Freenov 4" display has an onboard ESP32 microcontroller with external connections for I2C, SPI and a couple of GPIOs
IO
GPIO35 ADC1_CH7 input only
GPIO39 ADC1_CH3 input only
SPI
MOSI 23
MISO 19
SCK 18
CS 21
I2C
3.3V red
SDA 32 black
SCL 25 yellow
GND green
UART
RXD
TXD
GND
5V
BME280 data was transmitted over LoRaWAN to The Things V3 server then onto the Thingsboard desktop
similar example Thingsboard desktop displaying BME280 data plus data from other sensors
