2.4" TFT LCD mcufriend

Other Hardware Displays
1

Good morning ,
I wonder if it is possible tu use the 2.4" mcufriend simultany on multiple Arduino UNO ( or Atmega328 ) and if the answer is yes , how to do it ?

I have a project whit UNO's and 2.4" but one UNO do not have enough ports so I have to use a second one .

Best regards , Marco

2

Write down your pin budget e.g. external devices, switches, leds, ..., SD card, ...

There are tricks to share pins, save pins, ...
But as a general rule. Buy a Mega2560 or Due

David.

3

Mornig Dave ,

I have those but I like the UNO because I can use the ATMega328P as a stand alone and since I hace dosens of this IC .......

Thanks for your info ,
Have a nice day ,
Marco

4

I like Uno too. Which is why I suggested listing your pin requirements.

Yes, you could devote one Uno as an intelligent Slave display that receives commands from a second Uno.
The commands could be sent via USART or SPI.

David.

5

Thanks , I'll made a list of all connections . It's for a new radio project ( a multi bander ).
I'll take some time , but I'll do that and post it here.

Nice sunday
Marco

6

Hi David , I'm rewriting my sketch to a MEGA2560 ( have all the out-input pins I need )
In my sketch I use also a DDS-sketck from Richard Visokey (www.ad7c.com)
He use D2 & D3 for the rotary switch because those pins are interrupt pins.
Because I use a 3.5" mcufriend screen with your MCUFRIEND_kvb on the MEGA2560 , the pins D2 & D3 are in use .

  1. Can I change MCUFRIEND_kvb ( using 2 other pins ) ?
  2. I tried for my sketch the pins D18 ... D21 as interrupt pins but the sketch is not working ( I can not change frequency ) Is there something special whit those pins or are they compatible whit D2 & D3 ?
    I was looking in the data sheets but could not find a proper answer .

Marco

7

It is fairly easy to change pins in software but not very nice in hardware. You would be butchering the shield that is nicely mated with your Arduino.

Since the D18-D21 pins are accessible without touching the Shield, I would use INT0 - INT3 instead of D2, D3 (INT4, INT5)

I suggest that you read up on using the "other interrupt pins"

David.

8

OK , I'll do the reading , I tried this pins before but without succes . I'll try again.

Thanks

Marco

9

Hi , David , I did all the readings and know a little bit more now .

All I understood was that interrupts on a MEGA2560 are no so easy as on a UNO (??)

As this forum is about TFT , it is perhaps not the right place for my questions about ISR.

Sorry for that

Marco

10

There is no harm in posting about INTn on this Forum. Other Mega users will want to know.

I avoid the "Programming" Forum. It has too much traffic and a lot of dross.
But you might get some answers there.

It should be very straightforward to use INT0, INT1 instead of INT4, INT5 pins on a Mega2560.

David.