1
0
mirror of https://github.com/wfjm/w11.git synced 2026-04-25 20:01:57 +00:00
Files
wfjm.w11/tools/man/man5/lda-11.5
2022-05-15 11:52:11 +02:00

77 lines
2.1 KiB
Groff

.\" -*- nroff -*-
.\" $Id: lda-11.5 1237 2022-05-15 07:51:47Z mueller $
.\" SPDX-License-Identifier: GPL-3.0-or-later
.\" Copyright 2022- by Walter F.J. Mueller <W.F.J.Mueller@gsi.de>
.\"
.\" ------------------------------------------------------------------
.
.TH LDA-11 5 2022-05-13 "Retro Project" "Retro Project Manual"
.\" ------------------------------------------------------------------
.SH NAME
lda-11 \- absolute loader paper tape format
.
.\" ------------------------------------------------------------------
.SH DESCRIPTION
\fBlda-11\fP files contain an absolute binary executable for a PDP-11 system.
They were initially defined for usage with paper tapes, see
.EX
Paper Tape Software Programming Handbook DEC-11-OOPB-D Mar 1971
Paper Tape Software Handbook DEC-11-XPTSA-B-D Apr 1976
.EE
and later used in the disk-based \fBxxdp\fP system. DEC RT-11 and RSX tools
also supported this file format.
An \fBlda-11\fP file contains one or more blocks of the format
.EX
0 001 start frame
1 000 null frame
2 xxx byte count low
3 xxx byte count hight
4 yyy load address low
5 yyy load address high
... data
zzz block checksum
.EE
and the properties
.
.RS 0
.PD 0
.IP "-" 2
the byte count is the total number of bytes in a block, excluding the checksum
but including the 6 header frames.
.IP "-"
the checksum is the 2-complement of the sum of the whole block,
including the 6 byte header
.IP "-"
if the byte count is 6:
.RS 2
.PD 0
.IP "-" 2
if the load address is even, the loader will transfer control to that address
.IP "-"
if the load address is odd, the loader stops the CPU with a HALT
.PD
.RE
.PP
.
.PD
.RE
.PP
.
.\" ------------------------------------------------------------------
.SH "NOTES"
\fBlda-11\fP files can be created with \fBasm-11\fP, inspected with
\fBldadump\fP, and loaded into a system with \fBti_w11\fP.
.
.\" ------------------------------------------------------------------
.SH "SEE ALSO"
.BR asm-11 (1),
.BR ldadump (1),
.BR ti_w11 (1)
.
.\" ------------------------------------------------------------------
.SH AUTHOR
Walter F.J. Mueller <W.F.J.Mueller@gsi.de>