Linux/DS90UB954-Q1: DS90UB954A

Hi Steven,

Thanks for your support, and more details supplement:
1. After input port switching(RIN1 to RIN0), UB954 reserve 500ms for relocking.
2. Register 0x58[2:0] = 110b is used for the back channel rate. —— 50 Mbps (default for DS90UB953 CSI Synchronous back channel compatibility)
3. Settings used in UB954 as bellow:

//1920x1080@60fps
static struct regval_list ds90ub954_regs_channel0[] = {
{0x33, 0x01}, //open csi0, 4lanes
{0x4C, 0x01}, //TODO just port RX0 enable 0x01
{0x6D, 0x74}, //csi-2
{0x20, 0x20}, //TODO fwd enable RX0 0x20
{0x0C, 0x85}, //TODO Port 0 Receiver Pass, Port 0 Receiver Lock, Enable Port 0 Receiver. 0x85
{0x1F, 0x02}, //PLL 800Mbps
{0x58, 0xDE}, //enable pass throu 500MBps
{0x5C, 0xB0}, //SER_ALIAS_ID 8bit 0xB0
{0x5D, 0x34}, //slaveAliase[0] 8bit 0x34
{0x65, 0x34}, //slaveAliase[0] 8bit 0x34
{0x70, 0x1E}, //yuv422
{0x7C, 0xC0},
{REG_DLY, 0xC8}, //delay 200ms
{REG_DLY, 0xC8}, //delay 200ms
{REG_DLY, 0x64}, //delay 100ms
};

//1280x720@30fps
static struct regval_list ds90ub954_regs_channel1[] = {
{0x33, 0x01}, //open csi0, 4lanes
{0x4C, 0x12}, //TODO just port RX0 enable 0x01
{0x6D, 0x7F}, //coax
{0x20, 0x10}, //TODO fwd enable RX0 0x20
{0x0C, 0x96}, //TODO Port 0 Receiver Pass, Port 0 Receiver Lock, Enable Port 0 Receiver. 0x85
{0x1F, 0x03}, //PLL 400Mbps
{0x58, 0x78}, //enable pass throu
{0x5C, 0xB0}, //SER_ALIAS_ID 8bit 0xB0
{0x5D, 0x34}, //slaveAliase[0] 8bit 0x34
{0x65, 0x34}, //slaveAliase[0] 8bit 0x34
{0x70, 0x1E}, //yuv422
{0x7C, 0xC0},
{REG_DLY, 0x0A}, //delay 10ms
};

Best Regards,

Luke

Luke,
the 1 or 2 bad images is reported just after the switching from ub953 to UB913 or from UB913 to UB953?
can you reset the UB954 after switching? Some last frame data would be restored into the line buffer.

btw, how do you check the 1 or 2 bad image?

best regards,
Steven

Hi Steven,

1. It happens when switching from UB913 to UB953.（UB913 is used for transferring 720p images @30fps  and UB953 for 1080p images@60fps)

it works fine when switching from UB953 to UB913.

2. Reset UB954  after switching we also have tried, but it doesn't work.  With reset operation, it  seems to be more easier to get bad images.

3. After UB954 receive image,  system render it to screen as soon as possible. When bad image received, we could identify it by human eyes.

Best Regards,

Luke.Lan

If keep the UB954 is connected to UB913, does it have bad images?
also, the issue happened just after the switching? After run a while, it has no any issue?

From the chip design, if you reset the UB954 after the switching, the link should be stable! so pls identity it is chip switching issue or system switching issue.


best regards,
Steven

Hi Steven,

If keep the UB954 is connected to UB913, no bad images will be received. it works fine.
Issue happened just after the switching, bad image comes after switching a little while（ about 1s after）.
And then no more bad images will received.

"Bi-directional Control Channel CRC Error" is pair with the bad image showing up. So I more likely to believe it is
chip switching issue. And we will try add reset operation back after switching op, and make more contrast.

Best Regards,
Luke.Lan

I don't think this is switching issue, I think it is your board setting issue. please below analysis:
1. the issue is reported after 1s, the IC chip response time is so slow?
2. for the setting, i check your reg., when paired with UB913a, the csi2 port lane rate is 400Mbps, you should refer to page40 of UB954 to set the correct CSI2 port timing. question: why not keep the same CSI2 port lane rate for both ub953 and UB913?
3. if you have reset after the power-on, and have ~100ms delay, the link is becoming more robust. after reset, you should re-config the reg.
4. does it have other noise generation in the board after the switching? which could result into CRC error.
5. what is the PoC network design of UB954? which could result into CRC error.

best rgds,
Steven

Hi Steven,

1. Keeping same  port lane rate for both ub953 and UB913,  issue still cannot be resolved.  But it seems a little better than before.

    And ub953 use "coax cable mode-CSI Mode" and ub913 use "coax cable mode-Raw 10 Mode", which could not be change(we tried).

2. Replaced with bigger diameter coax cable(the best we can find),  bad images received will not be as frequency as before but still exits.

3. Our PoC design refers to the official document.(as attachment).  Hope you can help us review again.

Best regards,

Luke

new  settings:

```

//1920x1080@60fps                 
static struct regval_list ds90ub954_regs_channel0[] = {
    {0x01, 0x02}, //reset all
    {REG_DLY, 0x64}, //delay 100ms
    {0x33, 0x01}, //open csi0, 4lanes
    {0x4C, 0x01}, //TODO just port RX0 enable 0x01
    {0x6D, 0x74}, //coax csi  
    {0x20, 0x20}, //TODO fwd enable RX0 0x20
    {0x0C, 0x85}, //TODO Port 0 Receiver Pass, Port 0 Receiver Lock, Enable Port 0 Receiver. 0x85
    {0x1F, 0x02}, //PLL 800Mbps
    {0x58, 0xDE}, //enable pass throu 500MBps
    {0x5C, 0xB0}, //SER_ALIAS_ID 8bit 0xB0
    {0x5D, 0x34}, //slaveAliase[0] 8bit 0x34
    {0x65, 0x34}, //slaveAliase[0] 8bit 0x34
    {0x70, 0x1E}, //yuv422    
    {0x7C, 0xC0},                 
    {REG_DLY, 0xC8}, //delay 200ms
    {REG_DLY, 0xC8}, //delay 200ms
    {REG_DLY, 0x64}, //delay 100ms
};                                
                                  
//1280x720@30fps                  
static struct regval_list ds90ub954_regs_channel1[] = {
    {0x01, 0x02}, //reset all
    {REG_DLY, 0x64}, //delay 100ms
    {0x33, 0x01}, //open csi0, 4lanes
    {0x4C, 0x12}, //TODO just port RX0 enable 0x01
    {0x6D, 0x7F}, //coax raw10                                                                                                                                                                                                         
    {0x20, 0x10}, //TODO fwd enable RX0 0x20
    {0x0C, 0x96}, //TODO Port 0 Receiver Pass, Port 0 Receiver Lock, Enable Port 0 Receiver. 0x85
    {0x1F, 0x02}, //PLL 800Mbps
    {0x58, 0x78}, //enable pass throu
    {0x5C, 0xB0}, //SER_ALIAS_ID 8bit 0xB0
    {0x5D, 0x34}, //slaveAliase[0] 8bit 0x34
    {0x65, 0x34}, //slaveAliase[0] 8bit 0x34
    {0x70, 0x1E}, //yuv422    
    {0x7C, 0xC0},                 
    {REG_DLY, 0x0A}, //delay 10ms
};                                

```

Hi Steven,

During switching, ub954 just forwards one input signals（the other one is still power on）. And 954 won't configure remote camera, so alias names are both not used. does it matter?

why "so alias names are both not used" is got?

- "so alias names are both not used" what i mean is : remote camera used default setting.  UB954 won't use these alias name to configure remote sensor. And the remote cameras works fine on under default settings. 

 

Do you reset the UB954 after switching?

 - Yes, we will reset  UB954.