- Is it a limit of the screen itself?
- is it a limit of the Arduino?
- How it's connected?
- The image conversion (would a pre-converted file ready to be blitted be faster)?
Redraw rate on 2.2" 18-bit color TFT LCD display with microS
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Please be positive and constructive with your questions and comments.
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Redraw rate on 2.2" 18-bit color TFT LCD display with microS
I've watched this video http://youtu.be/H4fMNvYoCG0 and the draw rate of the screen is slower than I expected. I'd just like to understand what's causing this:
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Re: Redraw rate on 2.2" 18-bit color TFT LCD display with mi
It's a combination of SPI speed, the speed of the Arduino, and the speed of reading the SD card. Arduino has a small internal SRAM, so it has to transfer bitmaps from the SD card in small blocks. You can't fit an entire full-screen bitmap into SRAM.
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Re: Redraw rate on 2.2" 18-bit color TFT LCD display with mi
Thanks Rick, with the 2K SRAM I guess my ideal of full colour images being swapped instantly is never going to happen with an Arduino.
Would a Raspberry Pi be faster or will the limiting factor be the SPI speed?
Would a Raspberry Pi be faster or will the limiting factor be the SPI speed?
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Re: Redraw rate on 2.2" 18-bit color TFT LCD display with mi
On a Pi, SPI will be the limiting factor, but it should be quicker than an Arduino.
You might have a look at out PiTFT, with is a 2.8" touchscreen designed for use with the Pi.
https://www.adafruit.com/products/1601 - resistive touchscreen
https://www.adafruit.com/products/1983 - capacitive touchscreen.
You might have a look at out PiTFT, with is a 2.8" touchscreen designed for use with the Pi.
https://www.adafruit.com/products/1601 - resistive touchscreen
https://www.adafruit.com/products/1983 - capacitive touchscreen.
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Re: Redraw rate on 2.2" 18-bit color TFT LCD display with mi
Thanks again Rick, slightly larger than I was hoping for but it looks like my options are a bit limited in this regard :-)
Please be positive and constructive with your questions and comments.