The application continuously uses the graphics library to render text, fill areas, and draw images to the screen. Once a layer is completely rendered to, the graphics library increments a layer swap counter. The application periodically (at 1 second intervals) samples the layer swap counter and calculates the difference from the previous sample. This difference is shown as the Frame Update Rate (Hz). 

The following diagrams show the various software and hardware blocks used by each project: 

In this configuration, a 16-bit RGB565 frame buffer is stored in internal SRAM. Due to the limited size of the internal SRAM, only a single frame buffer can be used which can cause tearing to be visible as the GFX library draws on the screen. This project use the Low-Cost Controller-less (LCC) display driver to manage the DMA that transfers the framebuffer contents to the display. 

• Input system service and driver
• Time system service, timer-counter peripheral library and driver
• DMA System Service
• Low-Cost Controllerless (LCC) graphics driver
• I²C driver
• 16-bit RGB565 color depth support (65535 unique colors)
• JPEG and PNG images stored in internal flash

The Project Graph diagram below shows the Harmony components that are included in this application. Lines between components are drawn to satisfy components that depend on a capability that another component provides. 

Adding the “SAM E70 XPlained Ultra BSP”and the “Aria Graphics w/ PDA TMA4301B Display” Graphics Template component into the project graph will automatically add the components needed for a graphics project and resolve their dependencies. It will also configure the pins needed to drive the external peripherals like the display and the touch controller. 

The parent directory for this application is gfx_apps/apps/aria_benchmark. To build this application, use MPLABX IDE to open the gfx_apps/apps/aria_benchmark/firmware/aria_bm_e70_xu_tm4301b.X project. 

The following table lists configuration properties:

Important!

This application may contain custom code that is marked by the comments // START OF CUSTOM CODE ... and // END OF CUSTOM CODE. When using the MPLAB Harmony Configurator to regenerate the application code, use the "ALL" merging strategy and do not remove or replace the custom code.

There are two programming options. The primary option is the Micro B Embedded Debugger (EDBG) port. Power to the board can also be supplied via this connection. The secondary option is via the ICD4 debugger with the ICD4/PICKit 4 Target Adapter Board. (Power can be supplied by one of the USB Micro-B ports or via a bench supply.) 

The image below shows both the EDBG and the ICD4 connection options:

Configuring the 4.3” WQVGA Display requires disconnecting the ribbon cable that connects the display to the interposer board.

First, release the ribbon cable from the interposer board. Next, release the black clamp on the E70’s J2 connector and turn the display over. Finally, insert the ribbon cable into J2 and close the clamp.

The board and display are powered by a Micro B – USB A cable from PC to the “Debug USB” port on the E70 board. The ICD4 Debugger and ICD4/PICKit4 Adapter Board are connected as shown above. 

On start-up, the application will display a splash screen. 

After the splash-screen completes, the String Update benchmark screen is shown. In this screen, a counter is incremented at every application cycle. The screen demonstrates the rate at which the graphics library renders a string on the screen. This involves a fill operation that clears the background, lookup of the glyphs from the string library, and the drawing of the glyphs on the frame buffer.

The “Frame Update (Hz)” field shows the current or instantaneous rate at which the graphics library updates the label widget that shows the counter value. Touching the Frame Update value switches between the current value (curr) and the average (avg) value across 10 samples. 

Touching the “+” and “-“ buttons increases and decreases the size of the string, respectively. 

Touching the “Next” button switches to the Motion and Fill benchmark screen. In this screen, squares are showing moving across the screen. The Frame Update value is the rate at which the graphics library is able to render all the squares on the screen at their new positions. This involves a fill operation of the background color at the old location of the squares and a fill of the squares’ colors at the new position.

The number and size of the squares can be increased and decreased using the “+“ and “-“ buttons. If the maximum or minimum size is reached, touching “+” or “-“, respectively, will switch to a full screen fill of alternating colors. 

Touching the “Next” button transitions to the Image Decode and Rendering screen. In this screen, two images of the same size are alternately rendered between application cycles. This involves a fill of the background color, decode and conversion of the image to the frame buffer format, and the drawing of the image to the frame buffer. The Frame Update value is the rate at which the graphics library is able to render an image on the screen.

The size of the images can be increased and decreased using the “+“ and “-“ buttons. 

Touching the “<” and “>” buttons switches between the various image formats. The formats that are supported are PNG, RAW RLE 16-bit, RAW 16-bit and JPG 24-bit. RAW 32-bit pre-decoded in DDR is also supported in the PIC32MZ DA configurations with DDR memory