Additional Amounts
What it is
Up to six 20-character amount structures: account type (2), amount type (2), currency (3), C/D indicator (1), amount (12) — balances, cashback, tips.
Example values
2040840D000000010000Cashback (40) of 100.00 USD debit against checking (20).DE 54 on the wire
Bitmap position
DE 54 is bit 54 of the primary bitmap: byte 7, mask 0x04. A primary bitmap with only DE 54 present reads 0000000000000400 in hex.
Length
DE 54 is variable length (LLLVAR): a 3-digit prefix gives the length of the value in characters, from 0 to 120. A 12-character value is sent as 012 followed by the value. In ASCII the prefix is the bytes 30 31 32; dialects that pack lengths as BCD send 00 12 instead.
Size in the message
At most 123 bytes when the message travels as text (ASCII or EBCDIC), or 122 bytes in binary dialects that pack the length prefix as BCD.
Format an
Format an means alphanumeric: letters and digits.
Specification reference
Defined in ISO 8583:1987 (base). Card networks publish their own dialect tables (Visa BASE I / V.I.P., Mastercard CIS) that refine formats, lengths, and — for private-use elements — the entire layout. Always confirm against the interface specification you implement.