Question about VBP and VFP settings of SN65DSI84

Nao

Genius 4905 points

Other Parts Discussed in Thread: SN65DSI84

Our customer set the following setting on SN65DSI84 register.

1920X1080p @ 59.94/60Hz (Format 16)

This format is available only in a 16:9 aspect ratio.

Designers should be aware that this format was not defined at the time when EIA/CEA-861 was published.

Therefore, an861 type source box will probably not recognize this format in an 18-byte detailed timing descriptor.

0x09              0x00
0x0A              0x00
0x0B              0x00
0x0D              0x00
0x10              0x26
0x11              0x00
0x12              0x59
0x13              0x00
0x18              0x6c
0x19              0x00
0x1A              0x03
0x1B              0x00
0x20              0xc0
0x21              0x03
0x22              0x00
0x23              0x00
0x24              0x38
0x25              0x04
0x26              0x00
0x27              0x00
0x28              0x20
0x29              0x00
0x2A              0x00
0x2B              0x00
0x2C              0x16
0x2D              0x00
0x2E              0x00
0x2F              0x00
0x30              0x05
0x31              0x00
0x32              0x00
0x33              0x00
0x34              0x4a
0x35              0x00
0x36              0x24
0x37              0x00
0x38              0x2c
0x39              0x00
0x3A              0x04
0x3B              0x00
0x3C              0x10
0x3D              0x00
0x3E              0x00

LVDS display does not display test pattern.
However, if they change 0x36 register to 0x25 from 0x24 and 0x3A register to 0x03 from 0x04, LVDS display can display test pattern.

Do we need to add 1 or subtract 1 from original value, when we want to set VBP(0x36) and VFP(0x3A)?

Regards,
Nao

over 9 years ago

0 Joel Jimenez0 over 9 years ago

TI__Mastermind 18655 points

Hello Nao,
We are reviewing your question. Could you please provide the panel's datasheet?
Regards

0 Nao over 9 years ago in reply to Joel Jimenez0

Genius 4905 points

Hi, Joel

Thank you for your reply.
Our customer can't provide their panel setting and panel data sheet, because they did specialty connection to LCD panel.

I guess that one of several possibilities is the changing waveforme between SN65DSI84 and LCD panel on their system.
But we can't know all their system. So, we don't need to care the data path after SN65DSI84 on their system now...

Could you please review these register settings which can output waveform that they want, first?

Regards,
Nao

0 Nao over 9 years ago in reply to Nao

Genius 4905 points

Hi, Joel

I appreciate your feedback on this.

Regards,
Nao

0 Nao over 9 years ago in reply to Nao

Genius 4905 points

Hi Joel,

Could you please review that SN65DSI84 can be outputted test pattern of the EIA/CEA-861 format in these settings?

Regards,

Nao

0 Joel Jimenez0 over 8 years ago in reply to Nao

TI__Mastermind 18655 points

Hello Nao,

The DSI85 only supports the formats stated in the OpenLDI spec. 18bit single pixels, and 24-bit single pixel.

Regards

0 Nao over 8 years ago in reply to Joel Jimenez0

Genius 4905 points

Hi, Joel-san

Thank you for your answer.
Please reply bellow my question, if you have some idea.

> Do we need to add 1 or subtract 1 from original value, when we want to set VBP(0x36) and VFP(0x3A)?

Regards,
Nao

0 Joel Jimenez0 over 8 years ago in reply to Nao

TI__Mastermind 18655 points

Hello Nao-san,

It should work with the timing parameters stated in the panel's spec. Could you please use DSI Tuner to configure the device registers? Please, share screen captures showing the panel and DSI inputs in the tool.

Regards,
Joel

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Question about VBP and VFP settings of SN65DSI84