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SV2K17 Price

Was nicely surprised last week when I received this package Thanks Grey!

ivop

ivop

Making you own polyurethane cartridge cases

Here's how I made my first cartridge case.   First, I made two molds with tin cure silicone, the cheapest variant. Perhaps I'll make another one with platinum cure later. The cost of the molds is about 12,= euro's in total, but they can be reused several times. Not sure how many times yet. Might vary between 20 and 120, judging by the reports I read on the internet. It took 10-15 hours to cure until I could take the originals out of the mold. After that, I had them post-cure

ivop

ivop

Siddasm v2.1 (sid, sap and nsf disassembler) win32/win64 binaries

I just cross-compiled these from within Debian Linux (wheezy) and instead of only sharing them with the person I did this for, I thought I might just as well share them with everybody. Source code (GPL) is included. The win32 binary has been tested to work with wine under Linux. I cannot test the win64 binary, but it should work as well. Note that this is a command line utility. siddasm2.exe input.sid > output.asm. The output is in atasm format. It takes NSF (NES) and SAP (Atari 8-bit) files

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ivop

RMT File Format

I've spent some time reverse-engineering the file format used by Raster's Music Tracker. Included in the zip-file is rmtdump.c, a utility that came to be gradually, while exploring the format. There's also rmtformat.txt that describes the format in pseudo-assembly. rmtformat.zip

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ivop

SID 2 Gumby source code

Here's the source code of SID 2 Gumby.   It contains all the songs that were already posted in this thread: http://www.atariage.com/forums/topic/199103-teaser-sid-2-gumby/ plus five more songs:   Hubbard: Warhawk Thing On A String One Man And His Droid The Master Of Magic Laxity: Wisdom Sources are under the GPL3 license. The ADSR code is more or less the same as was used in atarisid3, so if you are going to patch other songs

ivop

ivop

SID Emulation Revisited, Atari SID III

I was delighted by the positive responses I got on my previous blog entry and on the forum about my SID emulator on the Atari 8-bit. I also was a bit disappointed that it turned out there already was an emulator eight years ago that I did not know about, that sounded pretty much the same as mine (some tunes were better, some were worse IMHO). But, this challenged me to improve my emulation A few days ago, I "broke" the 15kHz boundary, and after some bug fixes, I am pleased to present you "Atari

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ivop

SID Emulation, siddasm2 and shasm65

Long time, no blog.   Let's start at the beginning. In 2009 I wrote my first version of a SID Emulator, running directly on the Atari 8-bit hardware. The emulation loop ran in the main loop and synchronisation was done with STA WSYNC. I had created a raw register dump of a .sid file with a modified version of TinySid and every frame I left the main loop a few times for a few cycles to stuff the SID emulation engine with new values. I didn't take long to realize I didn't have quite enou

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ivop

Reverse Engineering the Macro-Assembler XE File Format

On the Atari 8-Bit Forum, Heaven/TQA asked for help with retrieving an ASCII version of his demo sources in Macro-Assembler XE format. Because I recently wrote a detokenizer for Mac/65, I thought it'd be fun to try this file format too. Here's the result. It successfully detokenizes all the sample .ASM files I found in his zip-file, but I'm sure some functionality is missing (at least three assembler directives). If you stumble upon files that fail, please send them to me and I'll update the det

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ivop

demac65: detokenize MAC/65 files

While I was browsing some old source code, I frequently stumbled upon MAC/65 tokenized files. Being too lazy to repeatedly start an emulator to convert them to (AT)ASCII and being unable to find a program online to detokenize them, I set out to write such a program myself. With some luck, I found a description of the format in the form of an old Analog Computing article. After that, it was pretty straightforward. Here's the source. Compile with gcc -W -Wall -O3 -o demac65 demac65.c. If you want

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ivop

Atari Eagle parts library

I finally compiled all the different Eagle parts I had drawn over the last year into a single Eagle library and adjusted them to be more or less uniform in look. While I was at it, I also added all missing chips and connectors. Currently, it contains the following parts:   74LS08 74LS14 74LS51 74LS74 74LS138 74LS158 74LS375 4050 4051 4164 6502C/Sally 6520A/PIA 27128/OS PROM ANTIC BASIC ROM Cartridge Cartrid

ivop

ivop

shasm65 - a 6502 assembler in sh

Here's the 6502 assembler I mentioned recently on the Atari 8-bit forum. The reasons to write this were:   1.) None of the assemblers I tried could generate correct code for code assembled to run in zero page and have forward references to other code in zero page, changing their operand in real-time. 2.) I wanted to write an assembler in sh (years ago, I came across osimplay, which I thought was pretty neat).   shasm65 is written in sh, the Unix Bourne Shell, with a few

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ivop

Turn monitor off in console mode Linux on an iMac G3

Recently I acquired an old Bondi Blue iMac G3 with a PowerPC @266Mhz and 64MB RAM. I upgraded the RAM to 128MB and installed Debian GNU/Linux on it. Runs like a charm. I intend to use it remotely to test big-endian compilations, so I wanted the built-in monitor to be turned off. After searching the net extensively, I was unable to find a solution. setterm -blank 1 does not work (no APM support on a G3), xdpms doesn't work either (no DPMS) and pmset is only available under Mac OS X. I did find a

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ivop

SID/SAP/NSF Disassembler

Two months ago I found a SID disassembler at the website of Covert BitOps. I rewrote large parts of it and added support for SAP and NSF (NES) files. It tries to do some simple code-flow analysis to determine code and data blocks. The output is compatible with ATASM. Because I want to avoid it'll bitrot on my harddisk, like so many other of my projects, I decided to post it here. Have fun.   Possible improvements (todo-list): * command line option to manually mark blocks as code o

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ivop

SIO2PC PCB

I have been back using my Atari 800 XL for about six months now. I bought a MyIDE cart to backup all my old floppies. Most of them were still readable. I did not really like the MyIDE cart though. Well, the cart is fine, it's mainly the patched O.S. It's a pity it doesn't support mixing SIO and IDE devices very well. So, I dug out my old SIO2PC cables. I had one MAX232 version and one using an MC1489. Both looked like crap (they were soldered very badly) so I decided to rebuild one. I "designed"

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ivop

Atari XL Look-Alike

Last weekend I visited a retro-computer fair. From a distance I thought I saw an Atari XL. Coming closer, it became clear it was something completely different.   There's remarkably little information to be found on the net about this little computer.   Old Computers Museum Heimcomputer (Germany)   There's some information about its successor on Wikipedia:   VTech Laser 200   I took a few pictures of the inside. Besides the usual 74LS logic,

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ivop

Test

Never thought I would get my own blog, but it seems now I have one.

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ivop

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