How to break input frame capture when necessary (required) frames is recieved on VPFE of DM6441

I am not sure whether I understood the question, but here is my comment.

I don't think your approach works.

If you need only portion of vertical lines, then you set SLV and NLV (shown below). By doing this, all other data are treated as blank data.

regards,

Sang-Yong

30-16 SLV0
Start Line, Vertical (Field 0)
Sets line at which data output to SDRAM will begin, measured from the
start of VD
*This bit field is latched by VD

14-0 NLV
Number of lines, vertical
Sets number of vertical lines that will be output to SDRAM for each field.
The number of lines output to SDRAM for each field = (NLV + 1).
*This bit field is latched by VD

Thank you for the prompt suggestion.

I didn't clearly mention my question.

During input data capturing, transfer stop request comes  suddenly as GPIO interrupt, then DM6441 needs to stop input data capture immdediately with N lines are captured (e.g. 100 lines).

Under this condition, after GPIO interrup comes, the follwing steps are done in ISR.

1.Set CCDCFG.VDLC = 1 and SYN_MODE.NEW =1 (data write enable).

2.Set VERT_LINES = 480,  after N lines transfer is completed, set SYN_MODE.WEN = 0

Trined above steps on DM6446 EVM and got input data capture is stopped immediately with a few lines capture after step 2 is done.

N frames + a few frames are stored to SDRAM.

My question is this way is the right thing for above requirement (stop input data transfer immediately when stop request comes suddenly)?

Any issue on this way?

Any other better solutiion?

Regards,

Kasuya

Did you try EXWEN?

I think you can control WEN timing through external signal by using this bit.

Regards,

Sang-Yong

NO, EXWEN is not set.

Is it necessary or better to set this bit?

You are saying that steps of my mentioned earlier is OK and EXWEN needs to be set?

Regards,

Kasuya

I meant that EXWEN is not set becuase external C_WE signal is not used in the system.

Regards,

Kasuya

EXWEN or Pre-fixed line number is the way you can use.

I don't have any idea about the method you used, but as some registers are able to be not shadowed. you can change during a frame. As you may know, shadowed registers can not be changed during a frame.

regards,

Sang-Yong

Thank you for your suggestion.

I need to confirm one thing for your comment.

You are saying that capturing the data during only active period of C_WE correct?

Is it necessary to set Pre-Fixed line number to capture the data correctly in case of using EXWEN for known valid line with C_WE ?

Or No need to set Pre-Fixed number in case of using EXWEN?

Regards,

Kasuya

I don't think it needs Pre-Fixed number.

The data writing is fully relying on EXWEN signal.

regards,

Sang-Yong