DS90UB935-Q1: Question about register setting

Hi Kurimoto-san,

- ALARM_BC_EN(Address 0x1E)

Q. Are the CRC_ERR_EN and LINK_DETECT_EN disabled at default? In case we want to let them enable, do we need to write "1"? If you wish to enable alarm, yes, you'll need to set those bits.

- CSI_POL_SEL(Address 0x20)

Q.  Writing "1" set the polarity as positive, Writing "0" set the polarity as negative. Is my understanding correct? If they are set to 0, it makes the P pin to positive and N pin to negative. If they are set to 1, it makes the P pin negative and N pin positive. If you route them according to the pin map description, you don't need to change this register.

- CSI_LP_POLARITY(Address 0x21)

Q.  Writing "1" set the polarity as positive, Writing "0" set the polarity as negative. Is my understanding correct? If they are set to 0, it makes the P pin to positive and N pin to negative. If they are set to 1, it makes the P pin negative and N pin positive. If you route them according to the pin map description, you don't need to change this register.

- BCC_CONFIG(Address 0x32)

Q. Customer doesn't use Back channel. Should they set the RX_PARITY_CHECKER_ENABLE bit at "0"? Why would they not use the back channel? The back channel is disabled on the deserializer side (reg 0x58 = 0x00). I would not disable back channel though. In sync mode, back channel is required, and also required for remote I2C programming.

- DATAPATH_CTL1(Address 0x33)

Q. Customer doesn't use DCA. Should they set the DCA_CRC_EN bit as "0"?  The customer should not be changing this bit. The DCA CRC is part of the forward channel sequence.

- REMOTE_PAR_CAP1(Address 0x35)

Q. What is the purpose of this register? Is there any problem to let this register as default? Leave as default.

- BC_CTRL(Address 0x49)

Q. Customer doesn't use Back channel. Should they let this register as default? Leave as default. Again, why aren't they using back channel?

Best,

Jiashow