ISO 8583 · Data fields

Field 54Additional Amounts

pyiso8583 starter profilesIndependent explanation

What this field describes

This variable length container is labelled Additional Amounts in the selected profiles.

Use the defined internal structure to associate each amount with its purpose and currency. The outer length is not a list of amount type assignments.

Compare the two profiles

Container settings from the pinned pyiso8583 source.
Settingdefaultdefault_ascii
Value encodingASCIIASCII
Length limitUp to 240 bytesUp to 240 bytes
Prefix3 ASCII bytes3 ASCII bytes

Length limits describe encoded values. They exclude any length prefix. The profiles can be customized; these settings do not establish the required fields or accepted values for a live connection.

Read the field boundary

Length prefix3 bytesASCII length
Field 54≤ 240 bytesASCII value

Read the 3 prefix bytes first, then read that many value bytes. Reject a length that exceeds 240 or the bytes remaining in the message.

Find it in the bitmap

Bitmap
Primary
Position
54
Byte
7
Bit in byte
6

Positions start at one. Bits are counted from the most significant bit of each bitmap byte. This calculation locates the field’s presence indicator, not its value.