DS90UB954-Q1: How to config DS90UB953 working with DS90UB954

Hi,

1) You cannot completely eliminate the VC ID, it can be re-assigned only. In register 0x72 of the DS90UB954 has VC set-up. By default, it's set-up so that if an input stream has a VC0 on the RX port selected, it gets assigned a VC0, an input of VC1 gets assigned VC1, VC2 is assigned VC2 and VC3 is assigned VC3. You can basically change these to as desired. VC0 can be re-assigned VC0, 1, 2 or 3.

2) So are you saying you don't want to configure PATGEN, instead send the imager data? Just keep the CSI Patgen turned off on both the Ser and Des. These are off by default, so as long as you don't turn it on, you're good.

3) The Data Type identifier is embedded into the CSI protocol. The SerDes can decode that information when transmitting CSI data.

Regards,

Mandeep Singh

Dear Mandeep:

     I've finished to make my ASIC driving a LCD display the color bar which was generated by DS90UB954,the mistake is caused by the mipi phy clock,i change it to 800MHZ and change the line period to  B93 (29.63us) and than i find the wave show that fps =30fps and  line period is 29.63us (29.63us*1125 =33.3375ms)

        now  i begin to send an real video stream but not colorbar to my ASIC.

        My source is 1920x1080 30fps Yuv422 in mipi package with 4-lane,400Mbps phy

        I find signal input to 953 is different from output from 954  like fellow

        input 953：

output on 954

①you can see every line period  is 29.63us ，953 input is about 355Mbps per one lane ，but at 954 csi output port，just less than half of one period is used for transmit a mipi line，what caused that？

②if my input not a raw sensor but YUV or RGB stream ，how to designe my serdes‘s mode pin and deserdes’s mode pin （i find if make 953  synchronous mode and 954 no-sycronize mode ，i cannot config 953 by 954 from remote side，but  all be config to  nonsynchronous i can config 953 from 954 at remote side）

Does there any exmple code  for  954+953 Transfrom YUV422 or RGB888

Hello,

Your setup looks ok except the CLKIN applied to the 953 should be 50MHz, not 25MHz for 4Gbps operation. For synchronous mode you don't need to have any local CLKIN applied to the 953 since it can use the back channel from the 954 as a reference but if you use non-syncronous mode where you apply a CLKIN directly to 953 then you need 50MHz for 4G and 25MHz can be used for 2G operation as per table 6 in the datasheet. (FC rate = CLKIN*80). 

Since you are using 445Mbps/lane, you will need ~1780Mbps of CSI bandwidth. The CSI bandwidth is calculated as f*64 for non-synchronous mode so if you use 25MHz at 953, then CSI bandwidth = 25*64 = 1600Mbps which is not enough. Please either use synchronous mode or switch the 953 CLKIN to 50MHz. Also remember for non-synchronous mode the back channel rate must be reduced from the 954 side as well so I would suggest simply using synchronous mode. 

Table 8 in the 953 datasheet explains the strapping for synchronous mode. 

Best Regards,

Casey 

Hello,

Has this issue been resolved?

Thanks,

Casey 

HELLO Casey:

          I've test the output signal wave,It's right ,but i've not  finish the display working.

Thanks  and i've solved this problem   ^_^