Systems, methods, and apparatus are described that provide for communicating coexistence messages over a multi-drop serial bus. A data communication method includes configuring a common memory map at each of a plurality of devices coupled to a serial bus, receiving at a first device coupled to the serial bus, first coexistence information directed to a second device coupled to the serial bus, generating at the first device, a coexistence message that includes the first coexistence information, and transmitting the coexistence message to the second device over the serial bus. The first coexistence information in the coexistence message may be addressed to a location in the common memory map calculated based on a destination address associated with the first coexistence information and a unique identifier of the first device.