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By the way, the voltage regulator of these AVR boards does not power the backlight of the screen, perhaps in 4.3" and 3.5" if possible, but from 5", the lack of power prevents the screen from working as it should .

It is necessary to power the backlight from a separate source, these screens can tolerate 5V on the TFT backlight.

You must specify the exact TFT you have, since those time tables come in your datasheet. Although the graphics chip is an EVEx, the screen used by the manufacturer has its own vertical and horizontal synchronization parameters, for that reason they must be added to the library. As Rudolph points out, he has been able to work with many variants of EVEx displays, but experience dictates that each display has specific parameters to make it work.

As the seeeduino board you have compiles without errors the code exported from ESE to gameduino, it will only be enough to add that time table to the ccp file of the library.

Share the link to the exact variant of your screen, from there you can review the datasheet to obtain the specific time tables.

As I pointed out previously, the library for gameduino is not adapted to other screens, although it is true that it has the initialization structure that allows several MCU platforms to be used, it is necessary to add the specific parameters of each EVE-x screen. It can handle screens from the FT80x, FT81x and BT81x families (in this last series, the memory section managed by QSPI has not been explored). Compared with the official library for EVE-x in the arduino IDE, the library for gameduino is quite simple to use, and greatly reduces the learning curve.

We must add the timing table of the TFT in particular (Hsync, Vsync, Voffset, Hoffset, etc.), and some aspects related to the frequency of the SPI-1 bus and the frequency of the EVE-x chip.

These data come in the datasheet on the screen.

That error has to do with your MCU, maybe the data cable is bad, maybe your MCU doesn't have enough power to run the display you want to connect.

Try another data cable but without connecting the screen.

It is relatively easy to add the code to export to a custom library for gameduino 23x. I attach the modified files and the steps that indicate where they should be copied into the Eve Screen Editor (ESE) folder.



The procedure works only for the ft81x family, however it's compatible with bt81x family, except for the instructions regarding flash memory


MCU: teensy 4.1
TFT: NHD FT813 5"
Wiring:
CS         --- 10
MISO     --- 12
MOSI     --- 11
SCK       --- 13
VCC       --- 3v3
GND      --- GND
BL-VCC  --- 5V
BL-GND --- GND


MCU: teensy 4.1
TFT: Riverdi BT817 5"
Wiring:
CS            --- 10
MISO        --- 12
MOSI        --- 11
SCK          --- 13
VCC          --- 3v3
GND         --- GND
PD/Reset   ---  24
BL-VCC     --- 5V
BL-GND    --- GND

In the case of the BT81x series it's necessary to connect the PD pin to a PWM pin (24), in order to create a reset during boot, otherwise the display chip will not initialize.

Some time ago I saw that it is possible to use the library for gameduino 2 with the EVE screens (FT800 and FT801), in fact the EVE Screen Editor (4.2.0) can export sketches with that library; so together with a friend (lightcalamar) we got to work (rather in the code) to investigate if it was possible to use screens like the EVE2 (FT813), EVE3 (BT815) or the EVE4 (BT817). With permission from its author: James Bowmann, we managed to modify the library for gameduino 23X, so that it could be used in conjunction with the SdFat library, instead of the SD library, all in the Arduino IDE environment.

The library is focused on STM32 boards like F103, F407, F411, F429, F746 and F767 and mainly on teensy 3.6, 4 and 4.1. The AVR and Due boards are very, very limited with the SdFat library, so we've left them out. At the moment the flash memory part has not been explored, however the other functions can be used perfectly.

The most advanced library we have is the GDSTx, however it needs some adjustments to upload it to github. The previous version is GDT4Xv134

Reviewing the way EVE Screen Editor v4.2.0 exports via pyton, I was able to add the option to export to the GDSTx custom library on FT81x boards (10, 11, 12 and 13), but with BT81x boards it hasn't been possible to get it. If the administrators allow it, I could share the modified program.

The screens I'm using are the NHD-FT813 5" on Teensy 4.1


And the Riverdi BT817 5" on Teensy 4.1

Specifically what screen do you have FT811, FT813, BT815, BT817, etc?

Well you could use the gameduino 23x library, with some tweaks regarding screen timings, you could run your hardware in the arduino IDE. Even the EVE Screen Editor app has the python script to export to that library. It is enabled for FT80x screens, but with some adjustments it can be adapted for the FT81x series, I have been able to make a BT817 screen work in the experiments.

Taking advantage of the post, you could share the download link of the EAB v2.4.1 version, it's video file conversion system is much superior to the most recent version available.

PS: By the way, I wish they could go back to the v241 video conversion engine in future updates.

To verify that the initialization of the screen is correct, in EVE 4 we have the possibility of loading a test screen through the CMD_TESTCARD () register.

According to BRT_AN_033_BT81X_Series_Programming_Guide, page 189:

Features of the testcard are:
• white border at the extents to confirm screen edges and clock stability
• red, green, blue and white gradients to confirm color bit depth
• horizontal and vertical checker patterns to confirm signal integrity
• circle graphics to confirm aspect ratio
• radial line pattern to confirm antialias performance

Two questions:

Did you calibrate the touch panel on your FT817?
Where do you store the 25 data of the touch calibration vector?

It is possible to connect the audio output line to the auxiliary of any speaker, just share GND between the MCU and the speaker. You can even use a bluethoth audio transmitter

Video: audio test