Getting Started: Running the “Graphics SSD1926 Demo”
This demo demonstrates hardware features unique to the LCD Controller Solomon Systech SSD1926. The two unique features are hardware JPEG decoder and hardware 4-bit SD card interface on the SSD1926.
The demo projects are created to run on supported Microchip Demo Boards and development hardware. Pre-generated hex files are available in the "Precompiled Hex" sub-directory found in the demo directory. These hex files are generated using the alternative hardware profiles found in the sub-directory named "Configs". Use the "Demo Compatibility Guide" when running pre-generated hex files appropriate for your hardware.
This demo only runs with QVGA (320x240) displays and not WQVGA (480x272). The reason for this is, there is only 256 Kbytes of RAM available on the SSD1926. If configured for a WQVGA display at 16bpp color depth, then 255 Kbytes of frame buffer space is required, and not enough RAM is left for the JPEG decoding. Hence this demo only runs on a QVGA setup.
The demo uses the Microchip Memory Disk Drive File System (MDDFS) Interface Library with the Microchip Graphics Library working on the Graphics LCD Controller PICtail™ Plus SSD1926 Board (AC164127-5) mounted with the SD Card receptacle.
To run the demo, copy all the files from the ‘Resources’ folder to the root path of an SD card. Then insert the SD card into the SD receptacle on the SSD1926 board. The card must be inserted before the demo starts. Assuming the PIC is programmed, then the demo should start running right away. The demo shows the JPEG file for files with the .JPG extension. The unique setup of this demo is that the JPEG data is not sent back to the PIC, rather, it is buffered and decoded by SSD1926 JPEG hardware decoder to the frame buffer on the SSD1926 RAM directly. The PIC firmware only manages the SSD1926 hardware registers and manages the file system via the MDDFS library. When displaying a JPG file, the SSD1926 frame buffer is set to use the YUV color mode. Resolution of the images must be less than 2560x1920 (maximum scale down factor supported by the SSD1926 is 8).
The demo will also play video files formatted as RGB565 for each frame. Use ffmpeg (http://ffmpeg.org) to do the video conversion, an example ffmpeg command line that outputs a video compatible with this demo is:
ffmpeg -i video.avi -s 320x240 -pix_fmt rgb565 video.rgb
The demo will attemp to play video files with the .rgb extension. When playing an RGB file, the SSD1926 frame buffer is set to use the RGB color mode.
To run the demo in the supported Development Board combination, set the proper hardware profile in the project HardwareProfile.h file:
· For other boards with QVGA display use:
#include "Configs/HWP_XXX_QVGAv1.h”
· For Multimedia Expansion Board use:
#include "Configs/HWP_MEB_XXX.h”
Where: XXX represents any of the selected Development Boards.
The hardware profile file name refers to the combination of Development Boards that are used to run the demo. Refer to the abbreviations summary (link) for details.
The table below shows the hardware set up for the selected Development Boards attached to different Display Boards:
Required Hardware/Configuring the Hardware
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Legend: |
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✓ |
Supported out of the box |
☒ |
Hardware compatible, will need firmware modification |
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☑ |
Supported, see limitations |
✗ |
Not supported, hardware not compatible |
Trademarks:
The Microchip name and logo, the Microchip logo, MPLAB, and PIC are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries.
PICDEM and PICTail are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries.
SD is a trademark of the SD Association in the U.S.A and other countries
Microsoft, Windows, Excel, and Windows Vista are either registered trademarks or trademarks of Microsoft Corporation in the United States and/or other countries.