ASN messages are sent with following segment
SN1**2*CA**24*EA
SN100 = segment identifier (SN1)
SN101 = assigned identification
SN102 = quantity shipped
SN103 = UOM for quantity shipped
SN104 = quantity shipped to date
SN105 = quantity ordered
SN106 = UOM for quantity ordered
The SN100, SN102 and SN103 are already supported