SNLA267A March 2019 – June 2019 DS90UB953-Q1 , DS90UB954-Q1 , DS90UB960-Q1
Pattern generator can be programmed to use different clock sources, the back channel recovered clock, the CSI2-clock, or the external CLK_IN pin. The output of the pattern generator is in 32-bit format. The output of the pattern generator and the output of the 32-bit CSI-2 parallel data are muxed before the data are transmitted to the TX data path module. Depending on the deserializer, the pattern generator output can be sent to a 40-bit mode or 28-bit mode data path.
The general flow for pattern generation is to enable CSI, CSI select, and pattern generation. Because the pattern generation simulates the CSI data, the pattern that appears must be configured before the rest of the parameters are defined. Because the data will come up as colored bars, the pattern configure register configures the number of color bars and the size of the block where fixed pattern is enabled.
The CSI data type must be defined through the Pattern Generator CSI DI register. While there are many different types of color spaces and various ways to define image data, such as RGB888 or YUV420 8-bit, the PGEN_CSI_DI register defaults to 0x24 indicating RGB888. This means a scale of red, green, and blue will define the colors that are used.
Because the pixels will be arranged in frames on the screen, the line size, bar size, active lines per frame, the total lines, line period, vertical back porch, and vertical front porch must be defined. Finally, the corresponding bytes are defined when the values for each color bar are referenced.
For more information regarding the register descriptions used during pattern generation, refer to the Digital Page 0 Indirect Register table in the 954 data sheet. Examples for pattern generation using the 954 and the 953 are found in Section 7.1.11 and Section 7.1.10, respectively.