CI-V Bus Collisions
Collisions can occur on an Icom CI-V bus for the same reason that collisions can occur on an Ethernet segment: two nodes send messages that overlap in time. Both protocols specify a means by which sending nodes detect collisions and warn receiving nodes, receiving nodes ignore damaged messages, and sending nodes retransmit damaged messages.
Collisions on a CI-V bus are only problematic if one or mode nodes fail to comply with the CI-V bus specifications for collision detection and message retransmission. The Icom PW-1 is the only hardware device known to send CI-V messages but not comply with these specifications; Commanders's Secondary CAT Port can be configured to overcome this limitation in the PW-1.
Collisions cannot occur on a CI-V bus whose only nodes are a PC running Commander and a single Icom transceiver whose CI-V Transceive function is disabled; additional passive (listen only) nodes like antenna switches, antenna controllers, and amplifiers can be attached to a CI-V bus without causing collisions. If a transceiver's CI-V Transceive function is enabled, collisions will occur, and all nodes must therefore comply with the CI-V specification; Commander's Verify CI-V command acceptance option should be enabled in this scenario.