Search:

Thank you so much! I'll definitely have a look at your code.

Casting away const won't work because it would involve detrimentally modifying an existing cross platform graphics library I wrote...

Sorry, to clarify what I'd like to see is this: readRect(int16_t x, int16_t y, int16_t w, int16_t h, uint16_t *pcolors) const;

The way to make const would be like I said, to move all that internal...

I've run into a problem with the optimized ILI9341 driver implementations by Paul S. and Kurt E.

The issue is this: Reading from the display can't be done with a const class reference because the...

Fair enough. :) I've been studying the datasheets side by side. I'm about as good at that as I am at reading sheet music, which is to say I'm terrible at it, but eventually get it if I squint. I'm...

I'm looking to fab a design I made with the teensy, but the exact processor used in the Teensy 4.1 is out of stock at digikey, and I don't see it on mouser at all.

I was wondering if I can use...

Thank you, I'll definitely take a look at that. I did figure out that the procs are different, but right I'm going to support the Teensy 4.1 which I own and can test. Supply problems prevent me from...

This is a pretty old thread, so apologies for revisiting it, but it's still linked at at the ILI9341_t3 library on GitHub via the README

I've been digging through the driver code, because seeing...

That's not quite what I'm wondering. I know what DC and CS do. I'm asking if there's some sort of hardware optimization for wiring the DC line to one of the hardware CS pins on the Teensy, because...

Background - why I'm even asking:
I wrote the htcw_gfx library which is a cross platform graphics library that's a bit more high level than Adafruit and TFT_eSPI, but not quite LVGL.
It does...

Prang is a MIDI score sampler originally developed on an ESP32S3.

I've ported it to the Teensy 4.1, though it will probably work with other teensies with small modifications.

It basically...

Yeah, I understand the pitfalls of it pretty well. And I realize that using the arduino SPI.h facilities is a performance tradeoff compared to going to the registers directly.

Here's the thing....

I'll tell you now, I use The STL sparingly when I'm working with little machines. Heap fragmentation is an absolute killer, and then there are issues of certain 8-bit procs not fully supporting it...

Paul, thanks for the information! I definitely will use your approach when I don't need it to the microsecond. In the application I wrote for this, the timing is critical, so I'll try your method and...

That's awesome advice for hobbyists, which I am not. I am evaluating the Teensy for the possibility of using Arm Cortex processors in future professional endeavors like I currently do with other...

Thanks! I'll bear that in mind, though I really only use the STL on IoT sparsely, and when I do use chrono it's because I want a cross platform way to do precision timing. It works on most platforms...

Good to know that's accurate enough! I had no idea.

I'm not sure where to put this, so here goes. I hope it's useful to someone.

I just figured out how to resolve the linker error with _gettimeofday() and to implement that function such that it...

Yeah, with htcw_gfx of course, you can write to an intermediary bitmap, but it's more work, and kind of bleh when all you want to do is draw some vector fonts anti-aliased to the screen.
...

KurtE,

I'd prefer to use htcw_gfx due to TrueType support, and the fact that I am the maintainer and I use it professionally, so I can add features and improve things as needed.

It currently...

rcarr, Oh I see. Then I misunderstood *you*. I apologize. I'd rather them not have to do a hardware hack but I'll keep it mind.

You misunderstood me. I'm not interested in creating a display controller, and if I was I would not use SDA reads.

I need to know how to do this in software with the teensy. I felt I was clear in...

Display controllers like the ST7789 and ST7735 and I think some other controller families have a strange facility they use for reading the frame buffer back off of the device (almost necessary for...

There's a complication with the MIDI host library for the Teensy (USBHost_t36) such that it won't easily integrate with other 3rd party libraries that deal with MIDI messages.

The reason being is ...

I've been tearing my hair out on google, on reddit, everywhere I could find to try to run this problem down. It had occurred to me that it might be software controlled, but I dismissed it, because I...

I ordered a teensy specifically for the USB host capabilities.
It didn't work.
I ordered a second teensy, again specifically for the USB host capabilities.
Unfortunately repeating the same thing...