Address assignment for devices coupled to a shared bus

A subordinate device, comprising:

• an interface circuit adapted to couple the subordinate device to a multidrop serial bus;
• and
• a controller configured to:
• receive a first broadcast command over the multidrop serial bus;
• decouple a daisy chain input of the subordinate device from a daisy chain output of the subordinate device;
• receive a second broadcast command over the multidrop serial bus;
• respond to the second broadcast command when a signal received through the daisy chain input is in an active state by:
• configuring a unique device identifier of the subordinate device using an address provided in the second broadcast command, and
• coupling the daisy chain input of the subordinate device to the daisy chain output of the subordinate device;
• and
• ignore subsequent broadcast commands after responding to the second broadcast command.

A data communication apparatus, comprising:

• an interface circuit adapted to couple the data communication apparatus to one or more multidrop serial buses;
• and
• a controller configured to:
• transmit a first broadcast command over a first multidrop serial bus, the first broadcast command being configured to cause a daisy chain input of a first subordinate device to be decoupled from a daisy chain output of the first subordinate device, and for each subordinate device in a plurality of subordinate devices coupled to the first multidrop serial bus, cause a daisy chain input of the each subordinate device to be decoupled from a daisy chain output of the each subordinate device, the daisy chain input of the each subordinate device being coupled to the daisy chain output of another subordinate device;
• activate a program enable signal that is coupled to the daisy chain input of the first subordinate device;
• and
• broadcast a first sequence of address configuration commands over the first multidrop serial bus, wherein the each subordinate device is configured to respond to a first address configuration command received after detecting the activated program enable signal at its daisy chain input, wherein the each subordinate device is further configured to ignore subsequent address configuration commands, and wherein each address configuration command is configured to configure a unique device identifier in a subordinate device that responds to the each address configuration command, and cause the daisy chain input of the subordinate device that responds to the each address configuration command to be coupled to the daisy chain output of the subordinate device that responds to the each address configuration command.

A method of data communication at a host device, comprising:

• transmitting a first broadcast command over a first multidrop serial bus, the first broadcast command being configured to:
• cause a daisy chain input of a first subordinate device to be decoupled from a daisy chain output of the first subordinate device, and
• for each subordinate device in a plurality of subordinate devices coupled to the first multidrop serial bus, cause a daisy chain input of the each subordinate device to be decoupled from a daisy chain output of the each subordinate device, the daisy chain input of the each subordinate device being coupled to the daisy chain output of another subordinate device;
• activating a program enable signal that is coupled to the daisy chain input of the first subordinate device;
• and
• broadcasting a first sequence of address configuration commands over the first multidrop serial bus, wherein the each subordinate device is configured to respond to a first address configuration command received after detecting the activated program enable signal at its daisy chain input, wherein the each subordinate device is further configured to ignore subsequent address configuration commands, and wherein each address configuration command is configured to:
• configure a unique device identifier in a subordinate device that responds to the each address configuration command, and
• cause the daisy chain input of the subordinate device that responds to the each address configuration command to be coupled to the daisy chain output of the subordinate device that responds to the each address configuration command.