i.MX6 HDMI_TX_INSTUFFING register.

[satoshishimoda]

Hi community,

We want to confirm whether our understanding for HDMI_TX_INSTUFFING register is correct.

Please see our understanding as below.

[Q1]

We understand this register is used and set when RGB -> YUV color space conversion is needed.

So this register is cleared when the color space conversion is not used.

Is this correct?

[Q2]

Regarding the meaning of "INSTUFFING", we understand "INSTUFFING" means "do not fill in data to the blank space of Table 34-2".

Is this correct?

Best Regards,

Satoshi Shimoda

[gusarambula · Accepted solution]

Hello Satoshi,

The TX_INSTUFFING register is intended to only overwrite when "de" is inactive, example code -

    /*enable tx stuffing, when DE is inactive, fix the output data to 0 */

writeb(0x7,HDMI_TX_INSTUFFING);

writeb(0x0,HDMI_TX_GYDATA0);

writeb(0x0,HDMI_TX_GYDATA1);

writeb(0x0,HDMI_TX_RCRDATA0);

writeb(0x0,HDMI_TX_RCRDATA1);

writeb(0x0,HDMI_TX_BCBDATA0);

writeb(0x0,HDMI_TX_BCBDATA1)

To the specifcs in your questions:

Q1 - It can be used always, it will overwrite the data in the black space, when CSC is not used the data can be "zero", when CSC is used the stuffing data will be "black" according to the colour space.

Q2 - Your understanding is correct.

[gusarambula]

Hello Satoshi,

I’m looking for more details on this although there is no much information available other than the information on the Reference Manual. This register is used only when using the ITU.601 standard YCC video, not all YUV standards.

I’ll let you know as soon as I have more information.