AM62A7-Q1: DSS VIDL register change can't work

Biao Li

Part Number: AM62A7-Q1

Hi Expert,

I would like to ask some questions about dss.
On am62a, I modified the register values of the VIDL part through devmem, mainly the color RGB offset, and the global alpha value. Theoretically, after the modification is completed, the screen display should change, but now there is no response. What could be the reason?

BR,

Biao

over 1 year ago

0 Krunal Bhargav34 over 1 year ago

TI__Mastermind 44585 points

Hello Biao,

Could you share the commands you used? Also, there is a go bit and have you tried setting that after changing modifying the register?

Regards,
Krunal

0 Biao Li over 1 year ago in reply to Krunal Bhargav34

TI__Expert 6440 points

Hi Krunal,

devmem2 0x302021FC w 128

This is to modify the global transparency parameter of VIDL. Its initial value is 255. customer changed it to 128 or 0, but nothing happened.

Biao

0 Krunal Bhargav34 over 1 year ago in reply to Biao Li

TI__Mastermind 44585 points

Hello,

VIDL1_GLOBAL_ALPHA is a shadow register and please set the GO BIT in the following register: 14.9.9.1.240.1 VP1_CONTROL Register (Offset = 4h) [reset = 40h ] . You can also read about shadow registers here: 12.10.4.1.13 DISPC Shadow Registers

Regards,
Krunal

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AM62A7-Q1: DSS VIDL register change can't work