8.5.7 Prevention of I2C Faults During Abrupt System Faults
In rare instances, FPD-Link III back-channel data errors caused by system fault conditions (from example, abrupt power downs of the remote deserializer or cable disconnects) may result in the DS90UB949A-Q1 sending inadvertent I2C transactions on the local I2C bus prior to determining loss of valid back channel signal. To minimize the impact of these types of events:
- Set DS90UB949A-Q1 register 0x16 = 0x02 to minimize the duration of inadvertent I2C events. Any device configuration, including this one, should be written as a part of the Init A sequence as shown in Figure 33
- Ensure all I2C masters on the bus support multi-master arbitration.
- Ensure all I2C masters on the bus support multi-master arbitration:
- 0x6A, 0x7B, and 0x37 are examples of good choices for an I2C address.
- 0x40 and 0x20 are examples of bad choices for an I2C address.