Hey guys,
sorry for opening another TFT Thread. I found so many threads on people who first bought a TFT and afterwards wondered how the heck it will work.
I would like to try differently:
Can anyone suggest a 2,8"TFT (or similar) for my Uno? There must be some out there, where no magic is needed to get the thing to work?
I found this one:
Many reviews state it works for the arduino. Any other suggestions?
thanks!
!! that one takes almose all I/O-lines.
I'd look for SPI-interface..
?? a bit smaller, but u got I/O-lines for other use
?? with touch screen
@manlac,
The shield in your link is very big i.e. 3.5" and I think it has no touchscreen.
Since it is a shield, it will plug into a Uno or Mega2560 and work first time. However, you have few spare pins left for sensors on a Uno.
Both the displays that knut_ny has suggested require serious interfacing work i.e. to provide 3.3V logic levels. And are not plug-in shields.
Yes, there are a couple of SPI plug-in shields with proper level converters.
E.g. from Waveshare, Seeedstudio, ...
Be realistic. A cheap 2.4" or 2.8" shield with a Mega2560 clone is cheaper than a SPI shield.
Hand-wiring level converters is a lot less reliable than plugging in a ready made shield.
If you say what sensors you want to use, we can tell you whether you have enough spare pins on a Uno.
David.
Thanks for your replies. Some soldering wont be an issue.
My Weather Station contains a TX and a RX:
TX: Arduino Nano, as Sensors Temperatur, Humidity, Daylight and Barometric pressure. Sending data via 433Mhz module
RX: Arduino Uno R3 (at the moment), gets Data from the 433 Mhz RX and saves all Data using a SD Shield. As second its connected to an LCD (16x02) and shows Temperature and Humidity.
Id like to build some kind of casing including the TFT on which I would like to show the data. The 1602 is functional but not pretty 
Id like to show like:
Temperature & Humidity at current time
Min/Max Day
and Barometric pressure....
If the Temperature and Humidity is sensed remotely and transmitted via 433MHz, your Uno only needs comms with the 433MHz (TX, RX).
Most parallel TFT shields have a SD card built in.
If your Uno is reading the Sensors, it needs spare pins for this. SPI sensors could be added to the SPI bus that the SD uses.
If you go for a 3.3V SPI display, you need to wire a Protoshield with extra electronics. Or buy a ready made SPI display shield.
David.
Isnt there a TFT which I can use like the 16x02 - more like plug and play?
You just have to write down a list of your requirements e.g.
433Mhz
Temperature
Humidity
SD card
Full colour TFT
...
preferably with part numbers or data sheets.
Even a 16x2 requires at least 6 GPIO pins.
An 8-bit parallel TFT needs about 13 GPIO. An SPI TFT needs about 5. You can see that you can run out of pins quite easily on a Uno.
OTOH, if you choose all your sensors, SD, display, ... to be SPI they can all share the same bus. Pretty much N+3 pins for N devices.
If all your devices were I2C, you only need 2 pins for up to 120 devices.
Learning how to write down a spec and calculate a pin budget is the way to get started on any design.
David.
As you said earlier...the RX Arduino just has to receive the data thats sent by the TX.
His work should be displaying the data I want and save the data to an SD card 
The RXD and TXD pins on a Uno are permanently wired to the USB bridge chip.
If your 433MHz receiver is stronger than the Uno USB wiring, you can connect it to the RXD, TXD pins (D0, D1).
I am reluctant to advise "sharing" 433 and USB. Either bootloading might be upset or your app might be upset.
You would normally put a "SoftSerial" on some different pins. But since a parallel TFT + SD uses all the pins, the Uno is already used up.
Which means that you have to buy an SPI shield or interface a non-shield SPI display.
David.
Ok, that sounds as serious as I was not hoping.
I think I am not experienced enough to interface a non shield display. AN using the SPI shield seems kind of complicated.
Is there any otther display that looks kinda neat (so not a 1602 or 2004) which can be used more easily?
I used a dht11, a bmp085, a 1702rtc and a 1.8" lcd and got all data on screen except the uno ran out of ram and could use the logger.
I have bought exactly this TFT screen and built a multi-temperature - relative humidity "station" around it See http://www.zonnepanelen.wouterlood.com/index.php/hobby-elektronica/1312-multi-temperature-metering.
There is an extensive description of how to connect the 3.5 TFT to a Nano (!) and do the measurements. There's also a .ino file.
If you run short of pins on your Nano you can build a Master-Slave configuration: the Slave takes the measurements, sends via a serial connection to the Master that displays on TFT.
Have fun Floris
