srec_formatted_binary man page

srec_formatted_binary — Formatted Binary file format


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.


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


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Referenced By

srec_cat(1), srec_input(1).

SRecord Reference Manual