DS90UB954-Q1: Continuous CSI clock without connected serializer

Juergen Suetterlin

Part Number: DS90UB954-Q1

Hi,

for system purposes we need a continuous CSI clock even if no serializer is connected.

Setting the CSI_CONTS_CLOCK does not help, because "CSI-2 Tx outputs will provide a continuous clock output signal once first packet is received."

If we do not receive a packet, there will be no clock.

Is there a possibility to enable the CSI clock even if no packet is received? Maybe one of the undocumented "CSI TX Reserved Registers"?

Best regards

over 6 years ago

0 Casey McCrea over 6 years ago

TI__Guru** 103215 points

Hello Juergen,

Setting register 0x38 = 0x07 should enable a CSI random test pattern. Also you need to set 0x33 = 0x03 to enable the transmitter. You can adjust the CSI speed in register 0x1F (before enabling the transmitter).

Let me know if it works.

Best Regards,

Casey

0 Juergen Suetterlin over 6 years ago in reply to Casey McCrea

Prodigy 240 points

Hello Casey,

yes, that registers works. But it is important to enable the transmitter first before setting this bit.

Just for documentation which sequence worked for me:

//1. disables CSI2 Forwarding.
I2cWrite2(0x20, 0x30)

//2. Configure CSI-2 Transmitter operating speed using the CSI_PLL_CTL register.
//Default Frequency: 0x02 (800 Mbps), 0x03 (400 Mbps), 0x00 (1600 Mbps),
I2cWrite2(0x1F, 0x02);

//3. CSI-2 enable for Port 0
//Enable the CSI-2 Transmitter for port 0 using the CSI_CTL register
//CSI_CTL Port 0: (Address 0x33). Value 0x03: enable continous-clock and csi-output
I2cWrite2(0x33, 0x03);

//Enable random test pattern generator
I2cWrite2(0x38, 0x07);

//Disable random test pattern generator
I2cWrite2(0x38, 0x00);

After disabling the test pattern generator the CSI clock still keeps running.

Btw: This has the same effect like activating the packet pattern generator.

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DS90UB954-Q1: Continuous CSI clock without connected serializer