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Record Format

An Intel HEX file is composed of any number of HEX records. Each record is made up of five fields arranged in the following format:


Each group of letters corresponds to a different field, and each letter represents a single hexadecimal digit. Each field is composed of at least two hexadecimal digits (which make up a byte) as described below:


: the colon that starts every Intel HEX record.
ll is the record-length field that represents the number of data bytes (dd) in the record.
aaaa is the address field that represents the starting address for subsequent data in the record.
tt is the field that represents the HEX record type, which can be one of the following types:
00 data record
01 end-of-file record
02 8086 segment address record
04 extended linear address record
dd is a data field that represents one byte of data. A record can have several data bytes. The number of data bytes in the record must match the number specified by the ll field.
cc is the checksum field that represents the checksum of the record. The checksum is calculated by adding the values of all hexadecimal digit pairs in the record modulo 256 and taking the two's complement.
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