Data element error indication
To identify an erroneous stand-alone, composite or component data element, and to identify the nature of the error.
UCF
Group response
To identify a group in the subject interchange and to indicate acknowledgement or rejection (action taken) of the UNG and UNE segments, and to identify any error related to these segments. It can also identify errors related to the USA, USC, USD, USH, USR, UST, or USU security segments when they appear at the group level. Depending on the action code, it may also indicate the action taken on the messages and packages within that group.
UCI
Interchange response
To identify the subject interchange, to indicate interchange receipt, to indicate acknowledgement or rejection (action taken) of the UNA, UNB and UNZ segments, and to identify any error related to these segments. It can also identify errors related to the USA, USC, USD, USH, USR, UST, or USU security segments when they appear at the interchange level. Depending on the action code, it may also indicate the action taken on the groups, messages, and packages within that interchange.
UCM
Message/package response
To identify a message or package in the subject interchange, and to indicate that message's or package's acknowledgement or rejection (action taken), and to identify any error related to the UNH, UNT, UNO, and UNP segments. It can also identify errors related to the USA, USC, USD, USH, USR, UST, or USU security segments when they appear at the message or package level.
UCS
Segment error indication
To identify either a segment containing an error or a missing segment, and to identify any error related to the complete segment.
UGH
Anti-collision segment group header
To head, identify and specify an anti-collision segment group.
UGT
Anti-collision segment group trailer
To end and check the completeness of an anti-collision segment group.
UIB
Interactive interchange header
To head and identify an interchange.
UIH
Interactive message header
To head, identify and specify a message.
UIR
Interactive status
To report the status of the dialogue.