DS90UB940-Q1: how to detect CSI pass condition and SOT/data errors

Dongbao Zhou

Part Number: DS90UB940-Q1

Hello Team,

Could you let me know how to detect 940 CSI pass condition as well as any SOT/data errors? I want to reset the CSI PLL by forcing unlock and lock.

Background: customer use 949+940, they meet low probability distortion issue when power up, can't recover automatically.

1. 940 lock keep high, disconnect and reconnect cable will recover (FPD-Link signal disconnected and reconnect only, keep system power)

2. Check 949 and 940 power sequence---good

I suspect it's CSI PLL issue but i need to do more test to verify.

Thanks.

Dongbao

over 4 years ago

0 Hamzeh Jaradat over 4 years ago

TI__Guru** 108190 points

Hello Dongbao,

can you provide screenshot of power-up sequence from 940, including all signals and timings as shown in Figure 45 and Table 102?

0 Jiawei Hu1 over 4 years ago in reply to Hamzeh Jaradat

TI__Expert 5565 points

Hi Hamzeh,

See screenshot as below. Also, could you kindly let me know how to detect 940 CSI pass condition as well as any SOT/data errors? Is there any register to indicate this? Thanks!

0 Hamzeh Jaradat over 4 years ago in reply to Jiawei Hu1

TI__Guru** 108190 points

Hello Jiawei,

As stated in the d/s, you can monitor indirect register 0x16[0]. This bit reflects the status of CSI PASS.

Also you can route the CSI PASS signal to GPIO0 or GPIO3 and monitor it with a scope.

There is no register can tell you if there is any SOT error or not.

Interface

Interface forum

DS90UB940-Q1: how to detect CSI pass condition and SOT/data errors