AN 889: 8K DisplayPort Video Format Conversion Design Example

ID 683547
Date 5/30/2018

Board Status LEDs, Push Buttons and DIP Switches

The Intel® Arria® 10 GX FPGA Development Kit has eight status LEDs (with both green and red emitters), three user push buttons and eight user DIP switches. The 8K DisplayPort Video Format Conversion Design Example illuminates the LEDs to indicate the state of the DisplayPort receiver link. The push buttons and DIP switches allow you to alter design settings.

Status LEDs

Table 2.  Status LEDsThe table lists the status that each LED indicates. Each LED position has both red and green indicators that can illuminate independently. Any LED glowing orange means that both the red and green indicators are on.
LED Description
Red LEDs
0 DDR4 EMIF calibration in progress.
1 DDR4 EMIF calibration failed.
7:2 Unused.
Green LEDs
0 Illuminates when DisplayPort receiver link training completes successfully, and the design receives stable video.

DisplayPort receiver lane count:

00001 = 1 lane

00010 = 2 lanes

00100 = 4 lanes


DisplayPort receiver lane speed:

00 = 1.62 Gbps

01 = 2.7 Gbps

10 = 5.4 Gbps

11 = 8.1 Gbps

User Push Buttons

User push button 0 controls the display of the Intel logo in the top right-hand corner of the output display. At startup, the design enables the display of the logo. Pressing push button 0 toggles the enable for the logo display.

User push button 1 controls the scaling mode of the design. When a source or sink is hot-plugged the design defaults to either:
  • Passthrough mode, if the input resolution is less than or equal to the output resolution
  • Downscale mode, if the input resolution is greater than the output resolution

Each time you press user push button 1 the design swaps to the next scaling mode (passthrough > upscale, upscale > downscale, downscale > passthrough).

User push button 2 is unused.

User DIP Switches

The DIP switches control the optional Nios II terminal printing and the settings for the output video format driven through the DisplayPort transmitter.

Table 3.  DIP SwitchesThe table lists the function of each DIP switch. The DIP switches, numbered 1 to 8 (not 0 to 7), match the numbers printed on the switch component. To set each switch to ON, move the white switch towards the LCD and away from the LEDs on the board.
Switch Function
1 Enables Nios II terminal printing when set to ON.

Set output bits per color:

OFF = 8 bit

ON = 10 bit


Set output color space and sampling:

SW4 OFF, SW3 OFF = RGB 4:4:4

SW4 OFF, SW3 ON = YCbCr 4:4:4

SW4 ON, SW3 OFF = YCbCr 4:2:2

SW4 ON, SW3 ON = YCbCr 4:2:0


Set output resolution and frame rate:

SW4 OFF, SW3 OFF = 4K60

SW4 OFF, SW3 ON = 4K30

SW4 ON, SW3 OFF = 1080p60

SW4 ON, SW3 ON = 1080i60

8:7 Unused