Arduino for STM32

I think the problem is in the HAL driver and/or display hardware. It works fine to display bitmaps and text, though.

I abandoned the STM32F746 Discovery for this project. The Teensy 3.2 processor and a 3.5" tft display does what I want.

Thanks for the response. As stated in the most recent post, use of the delay function is not the problem. A nonblocking approach using micros() shows exactly the same behavior as a blocking approach.

No method I've been able to come up with allows display of randomly placed dots on the screen ...

Well, the "draw hesitation" has nothing to do with the core function delayMicroseconds().

Here I replaced the call to delayMicroseconds() with a call to a function consisting of a "do nothing" loop written in assembly code. Same bizarre behavior, of pixels getting skipped, then filled in some time ...

Some progress was made by using delayMicroseconds() instead of delay(). Now, no pixels are skipped permanently, only transiently.

But the "draw" behavior clearly shows buffering of the graphics actions, as pixels initially skipped are filled in after an indeterminate pause. I don't understand how ...

Hi, All:

I have run across a non-deterministic problem that may be due to an interaction between the display hardware access and program writes to RAM.

I'm using the LTDC lib associated with this branch of the core: https://github.com/fpistm/Arduino_Core_ ... TEST_1.9.0

UPDATED PROBLEM SUMMARY ...

Problem solved!

I discovered that clearing the screen overwrote some critical program variable. The issue was resolved by specifically declaring the screen buffer as a global variable. Evidently malloc() does not properly observe some heap or stack boundary of program ram usage.

Fix: don't use ...

The TS library appears to perform unexpected, unauthorized writes to at least two distinct RAM memory locations, when the first call to .getPoint() is executed.

I'm using this branch of the 1.9.0 core: https://github.com/fpistm/Arduino_Core_STM32/tree/LTDC_TS_TEST_1.9.0

The offending code is the ...

That worked perfectly. Thanks very much!!

Please consider adding those instructions to the Wiki, for GitHub-ignorant Windows users like myself.

Thanks, I tried to follow those instructions (quote below), but they don't work on Windows.
3.1. Cloning the git repository to replace the stm32 core version package (1st method)

In the "<local Arduino directory>/packages/STM32/hardware/stm32/" do the clone:

git clone https://github.com ...

Hi, All:

I have the STM32F7456G Discovery board and would like to use the TFT display. I've gone through the standard procedure of installing the master branch of STM32 core, which works fine for a Blink program, but does not have the display enabled. Using Windows 10 and Arduino IDE 1.8.12

So, I ...