RoadTest Review of Bridgetek Embedded Video Engine ME817EV + Display - Varun Prasad Gokhale

Table of contents

RoadTest: Bridgetek Embedded Video Engine  ME817EV + Display

Author: varpg28

Creation date:

Evaluation Type: Evaluation Boards

Did you receive all parts the manufacturer stated would be included in the package?: True

What other parts do you consider comparable to this product?: Nil

What were the biggest problems encountered?: Initial Setup was a bit cumbersome, later it was smooth

Detailed Review:

Welcome to my RoadTest review about Bridgetek Embedded Video Engine  ME817EV + Display. 

I'll be talking about:

  1. General Overview of the Kit
  2. Literature and Tools Required
  3. Hardware and Software Setup
  4. Working of the board
  5. Testing of Applications
  6. Final Review

A] General Overview of the Kit:

In the package, I received was the Bridgetek Embedded Video Engine  ME817EV Evaluation Board and a 7 inches display from Riverdi. 

Here is the unboxing video of what I received in the package

Once the kit was unboxed, now it was time to go through the literature and understand the capabilities of the board.

 

B] Literature and Tools Required:

The ME817EV Board:

ME817EV is a customer evaluation board for Bridgetek 4th generation EVE chip, BT817. The ME817EV is used to develop and demonstrate BT817's graphics, touch and audio functionalities. The board is capable of supporting LCD panels with 40-pin LVDS interface, or 50-pin RGB interface. Backlight LED current can be adjusted using dip switches. Capacitive touch screens can be connected to the board through a 10-pin or 6-pin FPC connector. An Audio filter and amplifier are included on-board, allowing a 1/8W speaker to be driven. Audio source can be supplied from the BT817, or through a line-in connector.

The main functions of the ME817EV are as follows:

  1. USB Type-C or SPI connector for power supply
  2. 3.3V regulator. Takes 5V input and outputs 3.3V for on-board circuits
  3. AVDD/VGH/VGL/VCOM biasing voltages for LCD power
  4. LCD backlight driver. Drive current 120mA – 280mA with over voltage protection (OVP) of 35V
  5. 3 stage audio filter and power amplifier
  6. Audio connector for external speaker and audio line in
  7. 10-pin and 6-pin FPC connector for capacitive touch screen
  8. On board 16M byte SPI NOR flash memory
  9. FT4222H USB to QSPI master bridge
  10. 2x8 pin header for MM900 series microcontroller modules or generic MCU
  11. 20-pin 1.0mm FPC connector for generic MCU

Bridgetek provides extensive demo applications for their EVE family on their website: https://brtchip.com/SoftwareExamples-eve/

BT817 (and most other chip from Bridgetek’s families) has multiple engines sharing chip infrastructure. BT817 has following engines:

  • Graphics Engine
  • Graphics Coprocessor
  • Touch Controller
  • Audio Engine

Engines looks independent but they share some resources like memory. For example, configuration registers of each block are inside single shared region mapped to the same address space. You of course do not need to use all engines at all. Using BT817 without graphics engine usually does not make sense but if you do not want to use coprocessor, or touch inputs, or play music, then you do not need to configure and use them. All engines are very easy to use. 

Tools Required

  1. The ME817EV Evaluation Board + Display
  2. Screwdriver (To adjust the POTS)
  3. Multimeter
  4. External Interfacing Devices (Depending on Applications)
  5. Microsoft Visual Studio Code
  6. EVE Sample Apps
  7. EVE Toolkit

C] Hardware and Software Setup

Hardware Setup: 

  1. On SW2, set all 8 positions to ON. On SW1, set all 4 positions to OFF
  2. Set JP1 to short pin1-2
  3. Plug the USB Type-C cable to CN11-USBC2 connector, with the other end plugged to PC USB port (atleast 1.5A current rating).
  4. Trim variable resistors VR1-VR4 to get required LCD biasing voltages as: AVDD=8.2V, VGL=-7V, VGH=22V, VCOM=3.3V.
  5. Un-plug the USB Type-C cable to remove the power
  6. Connect the LCD display 40-pin FPC connector to CN9 through 40-pin FPC cable
  7. Connect the LCD touch 10-pin FPC cable to CN12
  8. Plug the USB Type-C cable to turn on the power

Software Setup

  1. Download EVE toolchain and sample application and Visual Studio Code.
  2. When re-compiling the sample application, select EVE_GRAPHICS_ME817EV in the Processor Definitions of SampleApp MSVC Property Pages, as shown in the screenshot below.

D] Working of the Board

  1. Once setup, connect the display to the board and run the setup application
  2. When I ran the setup the hardware and software, there was display on the LCD, but had an issue with the resolution.
  3. According to the preprocessor definitions in the Visual Studio project configuration, it was configured for EVE_DISPLAY_WVGA, which is 800x480. But the provided LCD has the resolution of 1024x600. I changed the preprocessor definition to EVE_DISPLAY_WSVGA. (right click project -> Properties-> C/C++ -> Preprocessor Definitions). Thanks to my fellow road testers who helped me solve this issue.

  4. Once these changes are made the board was working perfectly.

E] Testing of applications:

I tested out two applications:

1. The signal generator

2. Whiteboard App Testing

F] Final Review

This is my first road-test / product test review. I got to learn a lot while trying to test the board. I like the functional capabilities of the board in terms of LCDs. This kit is fabulous, but can be made even better with a few inclusions to the main kit. Addition of a speaker will help in testing out the capabilities of the speaker and also a small microcontroller or microprocessor chip can be included to test its compatibility with other I/O devices. Overall the board has worked well, had some initial setup issues, but after that everything was fine. A lot of things couldn't be tested due to delivery issues and the pandemic. Also a small suggestion, instead of providing the EVE Toolchain, the company can try providing the same services using Visual Studio code, making it user friendly.

A major application of this product would be a full fledged tab, utilizing the max of this board.

Anonymous