paulhorn/supermon64
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Updating README

Browse Source
This commit is contained in:
J.B. Langston
2017-02-07 11:11:16 -05:00
parent 33c258c553
commit b325298a3b
1 changed files with 37 additions and 29 deletions
Download Patch File Download Diff File Expand all files Collapse all files
README.md
+37 -29
View File
@@ -3,15 +3,22 @@ By Jim Butterfield
## Overview
Supermon64 is a machine-language monitor for the Commodore 64 written by
[Jim Butterfield](https://en.wikipedia.org/wiki/Jim_Butterfield). It
originally appeared as a type-in program in the
[Jim Butterfield](https://en.wikipedia.org/wiki/Jim_Butterfield).
The first version for the Commodore 64 originally appeared as a type-in program in the
[January 1983 issue of Compute Magazine](https://archive.org/details/1983-01-compute-magazine).
An earlier version was widely distributed by Commodore User's Groups and included on the
[demo diskettes](http://www.zimmers.net/anonftp/pub/cbm/demodisks/c64/starter-kit.d64.gz)
and tapes that Commodore provided with their hardware. An improved version followed in 1985,
updated to include the features in the built-in monitors for the Commodore Plus/4 and 128.
This is the version that is preserved here.
It was based on an earlier version of Supermon for the PET and VIC-20. An improved version
followed in 1985, updated to include the features in the built-in monitors for the
Commodore Plus/4 and 128. This is the version that is preserved here.
Supermon 64 was widely distributed by Commodore User's Groups and included on the
[demo diskettes](http://www.zimmers.net/anonftp/pub/cbm/demodisks/c64/starter-kit.d64.gz)
and tapes that Commodore provided with their hardware. It was also included as a type-in
program in the back of many books on machine language programming, including Rae West's
[Programming the Commodore 64: The definitive Guide](https://archive.org/download/Compute_s_Programming_the_Commodore_64_The_Definitive_Guide/Compute_s_Programming_the_Commodore_64_The_Definitive_Guide.pdf)
and Jim Butterfield's own
[Machine Language for the Commodore 64](https://archive.org/details/Machine_Language_for_the_Commodore_Revised_and_Expanded_Edition).
Here is a youtube video containing a quick demo: https://www.youtube.com/watch?v=MEjnMt_3wkU
## Contents
@@ -21,6 +28,8 @@ Original artifacts:
sources, instructions and binaries.
- [sprmon64.d64](sprmon64.d64) is a D64 image created from the self-dissolving
archive for use with VICE, disk drive emulators, or to create a real floppy disk.
- [supermon64.prg](supermon64.prg) is the original Supermon+64 binary taken from
the archive. The sources below will build an identical binary.
Modernized sources:
- [supermon64.asm](supermon64.asm) is the modernized Supermon+64 V1.2 source code with my comments.
@@ -329,19 +338,17 @@ accidentally disconnected by use of the run-stop/restore keys.
## Background
After working my way through Jim Butterfield's excellent
[Machine Language for the Commodore 64](https://archive.org/details/Machine_Language_for_the_Commodore_Revised_and_Expanded_Edition)
using his equally excellent monitor, I wanted to find some real assembly code to study,
and the software I had just been using seemed like a natural place to start. I started looking
for the sources online but for a piece of public domain software, it wasn't as easy as to find
as you'd think.
After working my way through Jim Butterfield's excellent book using his equally excellent monitor,
I wanted to find some real assembly code to study, and the software I had just been using seemed
like a natural place to start. I started looking for the sources online but for a piece of
public domain software, it wasn't as easy as to find as you'd think.
I found [this thread](http://comp.sys.cbm.narkive.com/KUAL6oqM/attn-jim-butterfiled-i-m-looking-for-supermon-64-source-code)
on comp.sys.cbm where someone asked for the sources and Jim Butterfield himself responded but
didn't have easy access to the sources. One person pointed to this
[modified version](http://www.ffd2.com/fridge/programs/supermon.s) but I wanted the original.
Someone else mentioned a file called SPRMON64.SDA at a now-defunct FTP
site. I searched for the filename and found what is apparently the last remaining copy on the internet
[modified version](http://www.ffd2.com/fridge/programs/supermon.s)
but I wanted the original. Someone else mentioned a file called SPRMON64.SDA at a now-defunct FTP
site. I googled for the filename and found what is apparently the last remaining copy on the internet
on a [gopher proxy](https://gopherproxy.meulie.net/sdf.org/1/users/rogertwo/prgs/cbm/c64/programming/).
I downloaded it and found that it contains what appear to be the original source and binaries
@@ -357,20 +364,21 @@ it as I went along.
As Jim noted in his usenet posting, the provided sources don't produce the final Supermon 64 binary:
I should note that, since Supermon+64 is relocatable code, the source
does not assemble into the final binary file. It may seem crude, but
I follow this procedure: (1) The source is carefully structured so
that there are no "dispersed addresses" such as might be created with
something like LDA #>VECTOR .. LDY #<VECTOR - every relocatable
address is two adjacent bytes; (2) I assemble the source TWICE, to
two different page addresses; the only difference in the binaries will
be the high-order bytes of the relocatable addresses; (3) a small
post-processing program blends the two binaries into a relocatable
package, adding a Basic driver to complete the bundle.
>I should note that, since Supermon+64 is relocatable code, the source
does not assemble into the final binary file. It may seem crude, but
I follow this procedure: (1) The source is carefully structured so
that there are no "dispersed addresses" such as might be created with
something like LDA #>VECTOR .. LDY #<VECTOR - every relocatable
address is two adjacent bytes; (2) I assemble the source TWICE, to
two different page addresses; the only difference in the binaries will
be the high-order bytes of the relocatable addresses; (3) a small
post-processing program blends the two binaries into a relocatable
package, adding a Basic driver to complete the bundle.
The sources for the relocator were not included in the self-dissolving archive, so I disassembled
the original supermon64.prg binary and reconstructed them from that. I also wrote a python script
that builds a relocatable binary according to Jim's instructions above. I have confirmed that the
Neither the sources for the relocator nor the post-processing program Jim refers to were included
in the self-dissolving archive, so I disassembled the original supermon64.prg binary and
reconstructed the relocator stub from that. I also wrote a simple python script that builds a
relocatable binary according to Jim's instructions above. I have confirmed that the
binary produced by assembling `supermon64.asm` and `relocator.asm` and then combining them using
`build.py` is identical to the original binary `supermon64.prg` provided in the archive.