Need help in buying a display for Teensy 3.6

Hello.
I'm finally going to buy a Teensy 3.6 board. I'm wondering what kind of a display would be good for it.
The display that I need needs to be at least 220x178 and have at least 256 colors. The display shouldn't have any kind of tearing effects or slow upload speed. I'm not sure should I buy an SPI display or a parallel display because I don't know if Teensy has a parallel bus like XMEGA. Does Teensy have a parallel bus DMA? If the display is SPI, what do you think if I use DMA and SPI to blit a framebuffer located on Teensy's RAM onto the display? Is it effective? What kind of a screen has a fast enough SPI to receive a whole frame before the tearing effect occurs? Does anyone have a video with a tech demo showing these requirements?

So far I have ST7775 and NT931-something-I-don't-know and both use 5V for the background LED and 3.3V for power and I/O which confuses me as I cannot supply both 3.3V and 5V from my Arduino. If I use 5V, the screen doesn't work and if I use 3.3V, the backlight is so weak that it's hard to see the picture. Does Teensy have a 5V pin along with the 3.3V I/O?

Please tell me what you think. Thank you!

Buy a ILI9341 WITH SPI! Do not buy the 8 bit parallel ones because they waste GPIO pins on the Teensy 3.6. It is also difficult or maybe even impossible to set up DMA with the parallel bus because data cannot be sent without the write pin being strobed. If you do choose to use a ILI9341 with the parallel bus, you can use my library (https://github.com/LudumDareDevelopment ... el-Library) which is generally faster than the default ILI9341_t3 SPI library for the Teensy. The fastest library and what I recommend is the Teensy 3.6 ILI9341 DMA SPI framebuffer library since it is extremely fast and can do updates above 50HZ. You can find the library here: https://forum.pjrc.com/threads/36706-IL ... y-3-6-only

Also, instead of the Teensy 3.6, I would buy the ESP32 since it's power efficient (it has a deep sleep mode) and is faster and cheaper. It also has SPI DMA transactions. I may be able to write a library for you that has fast refresh rates with no tearing

awesome101 wrote:Buy a ILI9341 WITH SPI! Do not buy the 8 bit parallel ones because they waste GPIO pins on the Teensy 3.6. It is also difficult or maybe even impossible to set up DMA with the parallel bus because data cannot be sent without the write pin being strobed. If you do choose to use a ILI9341 with the parallel bus, you can use my library (https://github.com/LudumDareDevelopment ... el-Library) which is generally faster than the default ILI9341_t3 SPI library for the Teensy. The fastest library and what I recommend is the Teensy 3.6 ILI9341 DMA SPI framebuffer library since it is extremely fast and can do updates above 50HZ. You can find the library here: https://forum.pjrc.com/threads/36706-IL ... y-3-6-only

As far as I can see, this display lets me choose when I want to refresh the screen. So if I want 30 frames per second, I should set a timer on Teensy to send the refresh command every 1/30th of a second?

awesome101 wrote:Also, instead of the Teensy 3.6, I would buy the ESP32 since it's power efficient (it has a deep sleep mode) and is faster and cheaper. It also has SPI DMA transactions. I may be able to write a library for you that has fast refresh rates with no tearing

Are you sure it's faster? Teensy 3.6 can go up to 240MHz while ESP32 can go up to 180MHz. Does ESP32 have a FPU? How do I load games onto it when compared with Gamebuino? I'd like to have some kind of a bootloader which either loads a game into Flash or RAM, but in a way that doesn't let the bootloader or the game overwrite the bootloader. Are programs for this microcontroller compilable in a way that they can be loaded to RAM with all of the code segments fitting nicely to not overwrite the bootloader's RAM code? Does ESP32 have MMU?

http://www.ebay.com/itm/ESP-32S-ESP32-D ... Swax5Y1OV3
Is this a good example of the board to buy?

Not sure what you mean by

Teensy 3.6 can go up to 240MHz while ESP32 can go up to 180MHz

? The ESP32 is clocked at 240MHZ and is generally faster. It also includes WIFI and other IOT stuff that could be useful. The ESP32 also obviously has both a hardware MMU and FPU. As for the bootloader, no one has written that for the Teensy or ESP32 so you may have to write that yourself.

Also, for the backlight and anything that needs 5V input, connect it to the VUSB or VIN pin and it will work. You can find the schematics for the Teensy here: https://www.pjrc.com/teensy/schematic.html

awesome101 wrote:Not sure what you mean by

Teensy 3.6 can go up to 240MHz while ESP32 can go up to 180MHz

? The ESP32 is clocked at 240MHZ and is generally faster. It also includes WIFI and other IOT stuff that could be useful. The ESP32 also obviously has both a hardware MMU and FPU. As for the bootloader, no one has written that for the Teensy or ESP32 so you may have to write that yourself.

Wow! Just wow! I'm buying this! Forget Teensy! ESP32 is cool now. I read somewhere that FreeRTOS is made for ESP32. I don't know is this real and under which license it is. I wouldn't wanna have all my work GPL'd or copylefted.

You didn't answer me this:

http://www.ebay.com/itm/ESP-32S-ESP32-D ... Swax5Y1OV3

Is this a good item? I'm definitely buying an ESP32. However, I'm wondering if there is a board like this on eBay with a Li-Po battery charger. I saw one, but it has a weird case for a battery that looks like those old normal remote control batteries, but I'm not sure. I don't know where to find those batteries. I'm looking for some kind of batteries like the one for MAKERbuino as well as a Li-Po battery charger for that.

The board on ebay is fine. I don't know how to power it though

What is special about this ESP32S? What's the S for? Does it have two cores and a MMU and all that stuff?

There's nothing really special about it besides the fact that it's really powerful. The best part is that it's much cheaper compared to the Teensy 3.6 which is 36$ USD

Does it come with the Flash chip? How big is the flash chip?

Most of your questions can be answered with google. It has 16 megabytes of flash which is way more than the Teensy 3.6. However, some of this flash is taken by a flash SPI DMA cache or something

I can't find that specific board. Maybe Google gives me different search results due to its Customer Relationship Management system thinking I'm not worthy of good results. Are you sure that that specific board has 16MB of Flash?

The ESP32 has 16MB TOTAL flash but only 4MB is available to the user. If you have more questions, visit the ESP32 forum and post there or go to the Wikipedia (https://en.wikipedia.org/wiki/ESP32).

Lol y'all should have messaged me. I've been hard at work getting the libraries running right.

If you want to use teensy I suggest ordering from the pjrc site. They also sell a couple different ili9341 screens as well for $10 us a piece. You will actually save about $12 doing so over ordering any where else.

I have libraries for both ESP32 and teensy3. We have been putting a lot work into debugging the libraries and getting frame buffer set up. With the new writeRect4bpp functions we can store and display full color bitmaps from flash or progmem at a fraction of the cost of multiple stack bitmaps. We just fixed the code so it can produce clear pixels by using zero in your writeRectbpp bitmaps. We do color with user defined custom palettes. This way the user can pick and choose any color they want and aren't hindered by the libraries default colors.

The only drawback is the tediousness of drawing the bitmaps by hand. There is no real program that convert the images to your palette...... Yet. But you only have to make one bitmap instead of 2-8 depending on colors.

The tile map looks great with the new functions as well. I'm impressed with myself that I was able to create function that used the bpp function as its core. As far as speed goes the esp32 will ultimately be faster and we have buffering added to it. And let me tell you it is fast using the game library. But the T36 has an sd card built in.

Spi is definitely the way you want to go. Less wiring and more support. Plus all the good libraries use it.

If you look me up on github you can see the T3 and ESP libraries. Ignore the master file. It does not work any better than the T3 and ESP libraries. It was the first working version but it's not very capable. I ended up changing the name to GameR-Iot. If y'all need any help getting your system going feel free to post, message or you can join us on face book for the latest developments. So glad you guys are willing to play with this.

The only things not working right yet are the title screen, pop up and collision.


Standard ESP has 4mb flash that can be used right away. You can buy flash chips that come in 4mb but you can only go up to 16mb total flash. They have dual cores which means you can set up one core to do This and core two to do that. It also has built in wifi but you will need an SD card module to store games. I use the EZSBC esp32 which is a great MCU. The only problem is that esp32 is really new so there's lil support for it. But like I said my libraries will get you set up and going.

Also...... Most Gamebuino and Competitor games can be updated to color with lil effort.

DO NOT..... Power your TFT using 5v. This will cause over heating and will damage your TFT and the plastic that surrounds it in a case. Ive already been there. Use only 3.3v or draw 3.7v straight from the battery. A 1500mah battery at 3.7v is all you need. For a charger the best option is to use the tp4056 charger(¢.99).