Polling of failed devices on an I2C bus

摘要

Polling of devices on an inter-IC (I2C) is provided. An expansion processor resides on a primary I2C bus. The expansion processor is coupled to a plurality of I2C sub-buses each of which may host a plurality of I2C devices. Data is transferred between the expansion processor and the plurality of I2C devices via the corresponding sub-bus according to an I2C protocol. Data transfer is in response to a request initiated by a bus master on the primary I2C bus. The bus master communicates with a target device residing on one of the sub-buses by addressing the expansion processor. The bus master informs the expansion processor of the target device by sending the expansion processor a number of the sub-bus on which the target device resides, and an address of the target device. A data stream bound for the target device is directed to the expansion processor which then echos it to the target device. Likewise, a data stream bound from the target device to the bus master on the primary I2C bus is transmitted to the expansion processor which then echos it to the bus master. Each of the target devices on the sub-bus can be polled to determine if they have failed. Failure of a device only affects operation of its sub-bus.