Description

Bridgetek BT820B MCU

The BT820B represents the fifth generation of the Embedded Video Engine (EVE) family, designed for creating advanced graphical interfaces in embedded systems. It enables the development of sophisticated, touch-friendly HMIs on large LVDS displays while retaining the familiar object-oriented programming model from previous EVE iterations.

This powerful graphics controller drives high-resolution LVDS displays (up to 1920 x 1200), offering smooth and complex interface rendering through a dedicated frame buffer in external DDR3 SDRAM, along with a 16 Kbyte display list. With direct access to storage devices like NOR/NAND Flash and SD cards, the BT820B can retrieve and display images, videos, animations, and fonts without overburdening the host MCU’s flash memory.

It also integrates live video seamlessly (up to 1920 x 1200 at 60fps), with an LVDS video input port that supports real-time video processing, effects, and image enhancements.

Touch functionality is enhanced, with support for external capacitive touch controllers through an I2C interface. Audio playback and effects are also supported, using either stereo PWM/Delta-Sigma or I2S outputs.

BT820 Block Diagram

A powerful graphics controller

If your application demands a visually stunning and sophisticated GUI built using lightweight software—and capable of running on even the smallest microcontrollers with SPI or QSPI interfaces—the BT820B series is an ideal choice.

At the heart of our display board, the BT820B controller stands as the most powerful member of the advanced graphics controller family, designed specifically for embedded systems requiring high-quality Human Machine Interfaces (HMIs).

The picture below shows a block diagram of EVE (Embedded Video Engine) board and the interfaces of BT820B controller to accompanying devices on the module.

Riverdi’s displays powered by BT820B graphics controllers feature advanced EVE (Embedded Video Engine) technology, seamlessly integrating image rendering, audio processing, and touch panel input for a rich user interface experience.

Leveraging an object-oriented approach, EVE technology simplifies the development of intelligent displays and significantly reduces time to market. For full technical details, please refer to the datasheet.

High resolution displays support

The fifth generation of Embedded Video Engine (EVE) technology introduces the BT820B graphics controller, delivering significant improvements and extended capabilities compared to the former four generations.

With the BT820B, Full HD resolution (1920 × 1080) is now available—marking a major leap forward in display performance. Compared to the previous EVE4 series, where the maximum supported resolution was WXGA (1280 × 800), the BT820B significantly raises the bar in terms of graphical output and interface possibilities.

Adaptive Scalable Texture Compression (ASTC)

One of the most important advantages, compared to the first two EVE versions, is the support for the Adaptive Scalable Texture Compression (ASTC) algorithm—first introduced in the EVE3 and maintained in the EVE4 and the new EVE5 series. This allows for significantly enhanced image quality without requiring greater bandwidth. In certain situations, the compression algorithm enables the use of smaller graphic files without compromising visual quality. As a result, it helps save considerable memory space that would otherwise be consumed by large font files and data-heavy images in EVE1 and EVE2 controllers.

See the datasheet for further information.

The Riverdi EVE5 boards include a dedicated flash memory chip, connected to the BT820B controller through a high-speed QSPI interface. This setup allows the controller to access and manage the memory contents directly, though doing so consumes some of the controller’s processing time and resources.

The flash memory on the EVE5 board is twice the size of that used in the previous generation EVE4, offering significantly more storage capacity for image resources.

The primary function of this flash memory is to store image files that will be displayed during the module’s normal operation. Based on tests using actual JPEG images with suitable resolutions, the flash memory on the EVE5 board can accommodate up to approximately 260 JPEG files—assuming high compression and usage with a 15.6” Full HD display.

However, these calculations should be treated as estimates. Due to the nature of JPEG compression, file sizes vary depending on image content—such as color complexity, contrast, and detail—not just resolution. For accurate storage planning, it’s recommended to repeat the calculation using the specific JPEG files intended for use.

Audio Playback

The BT820 controller is capable of audio playback through its integrated audio outputs. Audio files can be sourced from flash memory, an SD card, or streamed directly into DDR memory by the MCU. The Audio Engine within the BT820 handles retrieval of audio samples and routes them to the appropriate audio output channels.

For audio formats such as Linear PCM, μLAW, ADPCM, and S16, the Audio Engine duplicates the audio signal to both the left and right channels. However, when using the S16S format, stereo playback is supported: left channel data is directed to the left output and right channel data to the right output.

The BT820 supports PCM audio with 16-bit resolution only. Compatible sampling rates for Linear, S16, and S16S formats include 8 kHz, 16 kHz, 22.05 kHz, 32 kHz, 44.1 kHz, and 48 kHz.

It’s important to note that μLAW and ADPCM formats are not supported for standard audio playback. These formats are only supported when used as part of video playback, where the audio has been encoded using μLAW or ADPCM respectively.

High brightness, IPS TFT

Typical surface luminance for a high brightness, IPS TFT displays is 800 up to 1000 cd/m² which means it is very bright even outdoors. The full viewing angles allow the user to interact with the display in a natural and intuitive way from every side. Please see the datasheet for more features.

Customized displays

You can customize displays in many different ways.

• Change the color, shape, and size of the cover glass
• Have your logo printed on the cover glass (or any other graphics you might need)
• Add a different interface
• Enhance the brightness of the screen
• Change the thickness of the cover lens for the CTP
• Choose a different viewing angle of the display
• Change the pinout
• Request different gasket assembly

As you can see the possibilities are endless. All you need to do is choose.

We will help you to get the perfect tailor-made product.