SWRU543B January 2019 – June 2025 CC3230S , CC3230SF , CC3235MODS , CC3235MODSF , CC3235S , CC3235SF
A master may only start a transfer if the bus is idle. Two or more masters can generate a START condition within minimum hold time of the START condition. In these situations, an arbitration scheme occurs on the SDA line, while SCL is high. During arbitration, the first of the competing master devices to place 1 (high) on SDA, while another master transmits 0 (low), switches off its data output stage, and retires until the bus is idle again.
Arbitration can occur over several bits. The first stage is a comparison of address bits, and if both masters are trying to address the same device, arbitration continues to the comparison of data bits.
If arbitration is lost when the I2C master is initiating a BURST with the TX FIFO enabled, the application should execute the following steps to correctly handle the arbitration loss:
When the bus is IDLE, the TX FIFO can be filled and enabled, the TXFE bit can be unmasked, and a new BURST transaction can be initiated.