Close
0%
0%

1080p on an STM32

Connecting an LCD monitor to STM32

Public Chat
Similar projects worth following
This is the first iteration of this project. I'll post a detailed description in the next few days.

A monochrome VGA video output on an STM32L4 microcontroller, using DMA and SPI. It is necessary to use the DMA on a low-performance processor to achieve the necessary bitrate.

This is a nearly no-component monochrome VGA output project. It has a relatively low processor demand, too. This is achieved by deferring as much tasks to various peripherals as possible.

Utilized peripherals:
• Timers - for accurate timing and sync signal generation,
• DMA - for constant data flow,
• OCTOSPI - for fast serialization of the pixel data,
• Pripheral Interconnect Matrix - to lower the interrupt usage and for more accurate timing.

If you know a possible industrial use for this project or if you have any further ideas, let me know.
__________
More description coming soon. Stay tuned! ☠👈🏻

1080p

So far I achieved half-resolution of 1080p. The video signal is 1080p widescreen, HOWEVER, every pixel is doubled - every pixel in the memory is 2x2 pixels on the screen.

True 1080p is theoretically achievable. The RAM is somewhat limited on the STM32L4s but it;s still possible to fit. The OCTOSPI is capable of outputting the necessary 148 Mb/s data rate at a 74MHz system clock in the double data rate mode. The DMA also should be able to deliver at the necessary data rate of 1 transfer every 16 clock cycles.

So: coming soon! ☠👈🏻

Schematic

An absolute minimalistic design. Because all the 3 color lines on the VGA connector are connected together, the impedance matching cannot be done well - hence, some shadowing will appear in the image. 

This HW version is only a preliminary solution that I use to verify the viability of this project. A good solution has to have 3 independent drivers - all impedance matched individually to the 75Ω color lines. This can be achieved for example with a cheap logic gate IC from the 7400 family.

However, because there are only 2 colors, slight shadows don't really degrade the image quality.

System Block Diagram

View all instructions

Enjoy this project?

Share

Discussions

Similar Projects

Does this project spark your interest?

Become a member to follow this project and never miss any updates