D8M resolution&frame rate setting

From Terasic Wiki

Jump to: navigation, search

1. How to modify D8M resolution

Modify camera registers:

D8M register 1.png

In the demo, we use camera auto size figure to easily modify the camera resolution: just modify 0x3808~0x380B four registers.

For example: 640x480

D8M register 2.png



2. How to modify D8M frame rate

D8M frame rate 1.png

In this demo we configure camera SCLK to 150MHz

HTS: Horizontal total size

VTS: Vertical total size

fps =  150M / HTS/VTS

Take setting 640x480@60fps as example:

60 fps (combined with pll settings)

D8M frame rate 2.png

fps = 150,000,000/0x1200/0x021E
     = 150,000,000/4608/542
     ≈  60

Note: Horizontal blanking = HTS - Horizontal output width


As the camera mipi lvds data is processed by MIPI parallel Bridge IC, it will be limited by mipi parallel internal Linebuffer length, then, customer can try to set HTS value as larger as possible ( on condition that VTS value is still meet your requirement) to make a longer H blanking to reduce peak bandwidth requirements.



back

Personal tools