The sending application will initiate the sequence reset. The message is used to reset the value of the next sequence number to be transmitted.
If the GapFill field is not present (or set to N), it can be assumed that the purpose of the Sequence Reset <4> message is to recover from an out-of-sequence condition, therefore, the MsgSeqNum <34> in the header should be ignored (i.e. the receipt of a Sequence Reset <4> message with an out of sequence MsgSeqNum <34> should not generate resend requests).
If the Gap Fill field is present (and equal to Y), the MsgSeqNum <34> should conform to standard message sequencing rules.
The sequence reset can only increase the sequence number; if a sequence reset is received attempting to decrease the next expected sequence number the message should be rejected and treated as a serious error.
The '^' character is used to represent SOH character.