DS90UB954-Q1: Configuration for External FrameSync With Two DS90UB954 Deserializers

NOBUO FUJIHARA

Expert 8505 points

Part Number: DS90UB954-Q1

Hi Champs,

My customer would like to synchronize two DS90UB954 Deserializers as shonw in Figure 29 of DS90UB954 datasheet.

- Share same 25MHz and supply to REFCLK port of both 954.

- Set GPIO_0 for Backchannel FrameSynch, and supply external Frame Synch to both 954.

- Configure FS_CTL as 0x80 (External FrameSync from GPIO0)

- Configure BC_GPIO_CTL0 as 0x8A ( BC GPIO1=fixed low, BC GPIO0=FrameSynch)

With above setting, customer's board doesn't work properly.

Could you check if there is missing configuration?

Best regards,

Nobuo Fujihara

over 6 years ago

0 Palaniappan Manickam over 6 years ago

TI__Genius 10475 points

Hello,
Can you explain what they are seeing? What is the back channel rate set to (BC_FREQ_SELECT)?
Is the FS_SINGLE bit set to '1'?

0 Jonathan Nguyen over 6 years ago

TI__Expert 4555 points

Hi,

Is there anymore info you can provide other than the customer board not working properly? Did you set Register 0x10 (GPIO0_PIN_CTL0)? You can write 0x91 to this register to enable external framesync and enable GPIO0 (Refer to Table 7 of the DS90UB954 Datasheet). Please ensure that you are also selecting the correct port (Register 0x4C) and set the Back Channel Config (Register 0x58) to the appropriate settings.

I would recommend trying to get just one pair of the 953/954 working before using external framesync with 2 954s as the next step to debug.

Regards,
Jonny

______________________________________________________________________________________________________________________

Training on FPD-Link Serializer Deserializer devices and system: training.ti.com/fpd-link-learning-center

More information on IVI or ADAS FPD-Link products: www.ti.com/.../overview.html

0 NOBUO FUJIHARA over 6 years ago in reply to Jonathan Nguyen

TI__Expert 8505 points

Thanks for your support.

So far customer is reconsidering hardware setup and register configuration.

I will close this thread once.

Regards,

Interface

Interface forum

DS90UB954-Q1: Configuration for External FrameSync With Two DS90UB954 Deserializers