QUALCOMM Incorporated
LEGACY-COMPATIBLE 8-BIT ADDRESSING ON RFFE BUS FOR INCREASED DEVICE CONNECTIONS

Abstract:

Systems, methods, and apparatus increase the number of slave devices that can be connected to a serial bus. The bus protocol may be an RFFE protocol, an SPMI protocol, an I3C protocol or another protocol usable on a serial bus. In various aspects of the disclosure, a method performed at a device coupled to a serial bus includes receiving a first datagram at a slave device coupled to a serial bus, where the first datagram includes a 4-bit broadcast address indicative of a broadcast datagram, a first command directed to an invalid register address, and a payload, determining an encapsulation protocol associated with the invalid register address, and responding to a second command carried in the payload when an 8-bit slave address in the payload matches an 8-bit slave identifier allocated to the slave device.