srec_formatted_binary(5)

NAME
srec_formatted_binary - Formatted Binary file format

DESCRIPTION
This is the PDP-11 paper tape format, described in the DEC-11-GGPC-D PDP-11 "Paper Tape Software Programming Handbook" 1972.

The file starts with a character sequence which appears as an arrow when punched on 8-hole paper tape.
    0x08, 0x1C, 0x2A, 0x49, 0x08, 0x00

Then follows a byte count, encoded big-endian in the low 4 bits of the next 4 bytes. The high bits should be zero.

Then follows a 0xFF byte.

The data follows, as many bytes as specified in the header.

The trailer consists of the following bytes:
    0x00, 0x00,
and then a 2-byte checksum (big-endian).

The alternate header sequence
    0x08, 0x1C, 0x3E, 0x6B, 0x08, 0x00
is followed by an 8-nibble big-endian byte count.

  Size Multiplier
In general, binary data will expand in sized very little when represented with this format.

EXAMPLE
Here is a hex dump of a formatted binary file containing the data "Hello, World!".
    0000: 08 1C 2A 49 08 00 00 00  ..*I....
    0008: 00 0E FF 48 65 6C 6C 6F  ...Hello
    0010: 2C 20 57 6F 72 6C 64 21  , World!
    0018: 0A 00 00 04 73           ....s