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3.5" 320x480 Color TFT Touchscreen
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Please be positive and constructive with your questions and comments.

3.5" 320x480 Color TFT Touchscreen

by hawli on Sun Dec 08, 2019 4:05 pm

Hi, I connected the screen to the arduino mega 2560 and it seems to work kinda slow.
Here's the benchmark output:
Code: Select all | TOGGLE FULL SIZE
Using Adafruit 2.8" TFT Breakout Board Pinout
TFT size is 320x480
Found HX8357D LCD driver
Benchmark                Time (microseconds)
Screen fill              2236612
Text                     319624
Lines                    6416792
Horiz/Vert Lines         205832
Rectangles (outline)     130756
Rectangles (filled)      5549544
Circles (filled)         1572180
Circles (outline)        2709560
Triangles (outline)      1213216
Triangles (filled)       2884436
Rounded rects (outline)  822676
Rounded rects (filled)   5792544

Is this normal speed for this hardware?
I am trying to do a digital car gauge. The response time of the screen is very important.
Now even drawing a simple 1 color bitmap is slow. I know that it's all about clever code, but if it loads bitmap visibly slow, how can it do more things..
Is it possible to achieve a almost no delay effect?
Or should I switch to something else? nextion?

Posts: 1
Joined: Thu Dec 05, 2019 7:02 pm

Re: 3.5" 320x480 Color TFT Touchscreen

by Gianis on Fri Jul 10, 2020 8:33 am

Hi, is my first time writing here

I am interested in building a similar project for my car.
Project will be about a monitoring system for observing temperatures, pressure and RPM and acting accordingly for a diesel engine.

Inputs will be:

1. Exhaust Gas Temperature of Cylinder 1
2. EGT Cyl. 2
3. EGT Cyl. 3
4. EGT Cyl. 4
5. Lubrication Oil Temperature
6. Cooling Water Temperature
7. Scavenge Air Temperature
8. LO Pressure
9. CW Pressure
10 Ambient Air Temperature

Outputs will be:
1. Cooling Fan 1
2. CF 2
3. Flow controller Step motor (Cabin Heater)
4. On/Off Switch (for future use)
5. On/Off Switch (for future use)
6. Step motor for advancing/retarding engine fuel injection pump

Best case scenario is to have all of the above operations visible on my tablet and via internet access (3G data card and/or wifi) access for web radio, remote start stop, alarms, GPS position, WAZE, etc.

Any suggestions are welcome.

Multigauge application by PLX can sort out the graphical part on the tablet if the two software can be compatible.



Posts: 1
Joined: Fri Jul 10, 2020 7:26 am

Re: 3.5" 320x480 Color TFT Touchscreen

by waltr on Fri Aug 07, 2020 11:04 am

I know the OP is old but a new question is asked.

To get 'speed' on the display update one really needs to use the Parallel data/command interface.

The Serial (SPI or I2C) interfaces are a lot slower.
Posts: 296
Joined: Wed Jun 12, 2013 5:01 pm

Please be positive and constructive with your questions and comments.