DS90UB949 和 DS90UB940 配合使用：
视频部分是完美的。在940这一端屏幕上可以显示949传过来的图像。
但是关于音频部分，通过示波器看只能测量到940这端的pin15--MCLK 信号和pin13--I2S_CLK信号。
检测不到I2S_WC和I2S_DA信号。
以下是940这端的寄存器配置：
No size specified (using byte-data access)
0 1 2 3 4 5 6 7 8 9 a b c d e f 0123456789abcdef
00: 60 04 00 f0 fe 1e 00 18 00 00 00 00 00 00 00 00 `?.???.?........
10: 00 00 00 00 00 00 00 00 00 01 00 00 3b 40 00 00 .........?..;@..
20: 00 00 40 30 08 00 83 84 11 00 00 00 00 00 00 00 ..@0?.???.......
30: 00 00 90 25 01 00 00 a8 00 00 00 04 20 e0 23 00 ..?%?..?...? ?#.
40: 43 03 03 00 60 88 00 00 0f 00 00 08 00 00 63 00 C??.`?..?..?..c.
50: 03 10 00 01 80 00 00 00 00 7f 20 20 00 00 00 00 ??.??....? ....
60: 00 00 00 00 10 00 00 00 00 00 00 00 00 04 00 00 ....?........?..
70: 00 00 00 07 07 08 00 00 00 00 00 4d 02 00 00 00 ...???.....M?...
80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
90: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
a0: 00 00 8c 00 00 00 00 00 00 00 00 00 00 00 00 00 ..?.............
b0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
c0: 00 00 00 00 00 00 00 00 c0 00 00 00 00 00 00 00 ........?.......
d0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
e0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
f0: 5f 55 42 39 34 30 00 00 00 00 00 00 00 00 00 00 _UB940..........
