DS90UB984-Q1MEVM: only 2 green lights on. the MEVM board not work.

Hi,

The two LED's indicate the LOCK status. The second picture has no lock this could be caused by incorrect MODE_SEL strap configuration. I am not able to see MODE_SEL2 in the working EVM. Can you share the image with where it shows what MODE_SEL2 is.

Best Regards,

Gil Abarca

Hi

I checked the MODE_SEL2 setting are same. you could check it again,

below EVM works as expected. the MODE_SEL2 setting shows as below

  OK

Below EVM  NOT work,    the MODE_SEL2 setting shows as below.

-  NOK

Hi,

Ok, I can see they are the same configuration.

Lets move to the next step in the debug.

1. Are you using the same exact cable in both EVMs? Remove the cable from the OK EVM and connect it to the NOK EVM?
2. Are you using the same serializer for both Ok and NOK EVM? What serializer are using? Is it strapped to the same data rate as the NOK EVM?

Best Regards,

Gil Abarca

Hi

1. yes ,all the environement are same, we only replace the EVM on the same cable, same connector,  only the EVM is difffernet. one EVM work(we can see image on screen ), and another EVM doesn't work.

2. YES. the Serializer is MAX96717. the NOK eVM is new, when we got this EVM, it never works.

Hi,

GMSL serializers are not compatible with FPD-Link deserializer. MAX96717 should not be connected to a 984MEVM. I would recommend you to use an FPD-Link Serializer such as DS90UB983-Q1 which has DP input or DS90UB981-Q1 which is a DSI input.

Best Regards,

Gil Abarca

Hi

I suppose your answer may be not correct. curretly I have 2 piece of  984 MEVM in my hand, one is work, the other does not work, and the MODE_SEL2 setting are all same.

also before I purchase this EVM board, TI also give me the suggestion. show as below.

I bought 2 piece of this Board, the first works well,  but the other does not work.

if so, do you have any suggestion? return back to TI for checking?

Hi,

The FPD-Link Deserializer is only compatible with FPD-Link Serializers. GMSL uses a different protocol that is not supported by our devices.

Best Regards,

Gil Abarca

Hi 

sorry for some misunstanding info , MAX96717 is the serilarizer which is connected with Camera, We are using the Qualcomm 8295 chips. 

The serilarizer  on the 8295 chip is TI DS90UB983RTDRQ1  which is connected to the Display. currently we are using the 984MEVM as a converter to display the camera image on the PC screen.

Hi,

So the 984MEVM is connected to the 983? Can you make a diagram of how the 984MEVM is used in your system?

Best Regards,

Gil Abarca

Yes, we can make sure the system configration is correct. because we have one 984MEVM  works , another 984MEVM does not work, we only  repplace 984MEVM in the same system, one work, the antoher does not, what is the root cause? we can assume the another 984MEVM have somethings wrong, not our system.

I suggest to return back this 984MEVM for checking, I assume it is the HW issue or SW issue, it is not our system problem.

Hi. You see the configuration is same , but the two lights not ON, that means something wrong with  the LOCK status, it is not our system impact this Lock Status, you should figure out why the LOCK  lights not work as expected.

our timing is very critical, pls give me solution ASAP,  I recommand to return back to exchange a new one.

Hi, 

There are a couple of things I would like to try:

1. Please send me a picture of the 983 MODE_SEL strap mode
   1. I want to make sure that the serializer is configured to the correct strap mode.
   2. What Data Rate are you trying to use?
2. Also, IDx dip switches have 2 switches on. Only have the first one on and the last one turn it off.
3. MODE_SEL2 has daisy chain enabled do not enable the daisy chain if its not going to be used. Configure it to Daisy Chain OFF which is switch 8 and use the correct table in the MODE_SEL section to configure the rx data rate.
4. Can you communicate with the 984 locally? 
   1. Connect the NOK EVM to your computer and read register 0x0 can you read its I2C Physical Address?

Best Regards,

Gil Abarca

Hi

we have tried item2 and item 3,  still not working. 

for item 1 , we have no such kind of infomation,

for item 4. we have no script to read this I2C Physical Address, China Local TI could not support.

but for item1 and 4, it does not make sense to know such kind of info, because in our system we only exchange the 984EVM board, the 984 Board works correctly. so the only problem is 984 EVM Board.

if you could not find the rootcause, I strongly request to retyrn back to exchange a new one. our timing is very critical.

Hi,

?? ? said:

for item 4. we have no script to read this I2C Physical Address, China Local TI could not support.

What do you mean? Who have you communcating with in th China Local TI Team? I can probably ask them more information. 

Gil Abarca Ramos said:

Please send me a picture of the 983 MODE_SEL strap mode

1. I want to make sure that the serializer is configured to the correct strap mode.
2. What Data Rate are you trying to use?

?? ? said:

for item 1 , we have no such kind of infomation,

In order to have the LOCK LED turned on the 983 and 984 should be strapped to the correct data rate. If the data rates are not matching then there is no lock.

You need this infromation to ensure that LOCK is established. What is the 983 MODE_SEL0 and MODE_SEL1 strapped to ?

Finally, can you check the continuity between the CMC located in the FPD-Link traces? I want to ensure that the CMC is not damaged.

Best Regards,

Gil Abarca

Hi

1.How to check the 984/983 data rate, we can make sure the 983 data rate is correct,  because we have done many B2B tests, the only difference is 984 MEVM, also in customer side, this also works,  so the most probably reason is the 984MEVM, we have 2 984MEVM, only one is work,  if the 983 data rate is not correct, I assume none of the 984MEVM works, so the only reason is 984MEVM. you need to verify the 984 MEVM works correctly.

2.we don't konw how to  check the continuity between the CMC located in the FPD-Link traces. pls give some more info.

3. Local TI engineer is  Ao Sun,  he did not give any support for this issue, He ask me to get support from your side.

Hi,

I will close this e2e thread and continue discussing it over email.

Best Regards,

Gil Abarca