SLAVE DEVICE WITH LATCHED REQUEST FOR SERVICE

摘要

Consistent with one example embodiment, communications systems (100), using a serial data transfer bus having a serial data line and a clock line used to implement a communications protocol, incorporate latched service requests. Methods for one or more slave devices to request service from a master device (130) involve detecting a condition that asserts a request for service signal (162), at a common node (150) independent from the serial data transfer bus, to a master device of the bus. The request for service is latched (164), within the slave, such that the request for service remains asserted regardless of a change in the detected condition. The request for service is de-asserted (166) in response to interrogation of the slave, using the serial data transfer bus, by the master device. Devices may be configured as general purpose Input/Output devices, CODEC arrangements, or other slave devices, and may conform to I2C and/or SMBus serial communication specifications.