The Lines¶

Each line contains normal ASCII characters, and “high bit on[rq] characters, but the ASCII control characters are avoided (the high‐bit‐on con characters are not avoided). Normal line termination characters (CRLF or LF, depending on your system) are used.

The presence of high‐bit‐on characters makes this format unattractive to send via email, as it must be wrapped as a binary attachment, increasing its size.

In general, a single byte per byte is used to encode values, however some values use two bytes, according to the following table:

The Fields¶

Each line consists of 5 fields. These are the type field, length field, address field, data field, and the checksum.

Type

The type field is a 1 character field that specifies whether the record is data (0x43), or termination (0x47).

Record Length

The record length field is a 1 byte field that specifies the number of bytes in the record, excluding the type and record length fields.

Address

This is a 4‐byte address that specifies where the data is to be loaded into memory.

Data

The data field contains the executable code, memory‐loadable data or descriptive information to be transferred.

Checksum

The checksum is an 1‐byte field that represents the least significant byte of the one's complement of the sum of the values represented by the bytes making up the length, address, and data fields.

Record Types¶

0x43 (#)

A record containing data and the 4‐byte address at which the data is to reside.

0x47 (')

A termination record. The address field may contain the 4‐byte address of the instruction to which control is passed. There is no data field.

Size Multiplier¶

In general, binary data will expand in sized by approximately 1.5 times when represented with this format.