DLP4710EVM-LC: About LED Status

Keisuke Goto

Intellectual 600 points

Part Number: DLP4710EVM-LC
Other Parts Discussed in Thread: DLPC3479, DLPC-API, DLPA3005

Hi,

What kind of LED error does Byte2LEDStatus in ReadSystemStatus(D1) represent?

I have disconnected the LED of the EVM and checked the LEDStatus, but it does not show any error.

Regards,

Goto

over 3 years ago

0 Austin Snyder over 3 years ago

TI__Genius 12575 points

Hello Goto-san,

Welcome back to the E2E forum.

Read System Status (D1) is a general system status read. The return parameters are described in Section 3.7.2 on page 73 of the DLPC3479 Programmer's Guide.

Kind regards,

Austin

0 Mayank Khandelwal over 3 years ago

TI__Genius 9971 points

Hello Goto-san,

Did you leave the connection floating? Also, which LED did you disconnect?

Regards,

Mayank

0 Keisuke Goto over 3 years ago in reply to Mayank Khandelwal

Intellectual 600 points

Hi Mayank-san, Austin-san,

Thank you for your response.

According to the DLPC3479 Programmer's Manual, bits 5 to 3 of LEDStatus indicate the error status of each LED.

However, there seems to be no description of under what circumstances it becomes "Error".

To see under what circumstances the LEDStatus becomes "Error", I disconnected the EVM connectors J40 and J42 to check the LEDStatus.

I expected the LEDStatus to show "Error", but since it showed "No Error", I understood that it was not for detecting a broken LED.

Can you please tell me under what circumstances bits 5 to 3 of LEDStatus show "Error"?

Regards,

Goto

0 Vivek Thakur over 3 years ago in reply to Keisuke Goto

TI__Mastermind 22830 points

Goto-San,

Thank you for your patience. Our team member will get back to you in couple of days.

regards,

Vivek

0 Keisuke Goto over 3 years ago in reply to Vivek Thakur

Intellectual 600 points

Hi Vivek-san,

I'm waiting for your answer.

Regards,

Goto

0 Mayank Khandelwal over 3 years ago in reply to Keisuke Goto

TI__Genius 9971 points

Goto-san,

We have figured out that this issue is due to discrepancy in the ESW.

We are working to fix it. The fix for it will be available in the next maintenance release.

Regards,

Mayank

0 Keisuke Goto over 3 years ago in reply to Mayank Khandelwal

Intellectual 600 points

Hi Mayank-san,

Thank you for your response.

I understand that there was a problem with ESW.
I have two questions.

Can you please tell me when the LED Status is essentially an error?

When is the next maintenance release scheduled?

Regards,

Goto

0 Vivek Thakur over 3 years ago in reply to Keisuke Goto

TI__Mastermind 22830 points

Goto-san,

We don't have a release date for this fix yet.

We will get back to you on the other question - LED status error.

regards,

Vivek

0 Keisuke Goto over 3 years ago in reply to Vivek Thakur

Intellectual 600 points

Hi Vivek-san,

Thank you for your response.

I hope for a quick fix.

Also, I look forward to your answer to another question.

Regards,

Goto

0 Philippe Dollo over 3 years ago in reply to Keisuke Goto

TI__Mastermind 28005 points

Goto,

Thanks for your patience. I believe the team is still working this issue. We will post back here as new information develops.

Regards,

Philippe Dollo

0 Mayank Khandelwal over 3 years ago in reply to Philippe Dollo

TI__Genius 9971 points

Goto-san,

The team looking into this query in detail, it was found out that the discrepancy is in the Software Programmer's Guide and not in the ESW.

Bits 3,4,5,6,7 of Byte 2 (LED Status) in Read System Status command do not have any significance and should be ignored.

This discrepancy will be rectified in the next version of the Software Programmer's Guide.

Regards,

Mayank

0 Keisuke Goto over 3 years ago in reply to Mayank Khandelwal

Intellectual 600 points

Hi Mayank-san,

I understood LED status is not implemented.

Thank you for your support.

Regards,

Goto

0 Mayank Khandelwal over 3 years ago in reply to Keisuke Goto

TI__Genius 9971 points

Goto-san,

Thanks for your confirmation.

Regards,

Mayank

0 Keisuke Goto over 3 years ago in reply to Mayank Khandelwal

Intellectual 600 points

Hi Mayank-san,

I'm sorry for repeating myself, but I have an additional question.

I would like to detect a broken LED, can you tell me what is the recommended hardware method?

Regards,

Goto

0 Austin Snyder over 3 years ago in reply to Keisuke Goto

TI__Genius 12575 points

Hello Goto-san,

Many multi-meters have an LED check mode. If you have a multi-meter available, please check to see if this mode is supported. If it is, enter the mode and attached the leads to the LED.

If a multimeter is unavailable, a current can be applied to the LED to check its health. Please be sure to limit the current to avoid breaking the LED while checking.

Please note that these tests should be done with the LED disconnected from the board.

Regards,

Austin

0 Keisuke Goto over 3 years ago in reply to Austin Snyder

Intellectual 600 points

Hi Austin-san,

I'm sorry, I was a little wordy.

I am concerned about the LED breaking while the light is on in light control mode,

and I wish I could have detected that in the DLPC-API status, but I found I could not do that this time.

So I was asking if I could add some hardware to detect that.

Regards,

Goto

0 Austin Snyder over 3 years ago in reply to Keisuke Goto

TI__Genius 12575 points

Goto-san,

No need to apologize. I may have misunderstood your question.

I will have to defer the question to my colleague. Please expect a response by the end of the week.

Regards,

Austin

0 Keisuke Goto over 3 years ago in reply to Austin Snyder

Intellectual 600 points

Hi Austin-san,

Thank you very much. If there is a better way, please let me know.

Regards,

Goto

0 Philippe Dollo over 3 years ago in reply to Keisuke Goto

TI__Mastermind 28005 points

Goto,

It sounds like you are concerned about the operation of the LED. The DLPA3005 is the power management IC for this EVM, so you should consult the datasheet for this part for information about the output current and its associated circuitry connected to the LED.

https://www.ti.com/lit/ds/symlink/dlpa3005.pdf

As long as you operate within the recommended operation conditions in this case (and the LED you are using is rated for the range of possible output currents) you should be OK.

I hope this helps.

Regards,

Philippe Dollo

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DLP4710EVM-LC: About LED Status