psidTool is a command-line tool for creating (from C64 files)/manipulating/extracting (to C64 files) 'PSID' files.
Aha... What is 'PSID' then?!
What, you mean you were never a hardcore Commodore 64 freak (surf to http://www.c64.org!), spending those night you were supposed to be studying on optimising your new demo-effect to use 3 less clock cycles per iteration?! You mean you never listened to - even composed - the great SID music from this machine, enjoying the fab sweeping filter-effect of the snare sound of Artline Design's touching music? (The place to get 'PSID' music is, of course, the High Voltage SID Collection.) Oh, you hate those soft and nice sounds, calling them geeky, preferring trashy techno, digital reproductions of real instruments, and real girls instad of 180*200 reproductions instead??? Well, in that case, this program is certainly not for you! :-)
If you, on the other hand - and like the author of this program, who was (and still is, I guess ;-) one of those freaks, spending night after night coding 6510 assembler and composing music for our group LASER Inc. - were once part of the C64 scene, you are almost certainly familiar with PlaySID; a (now) cross-platform 6510 and 6581 SID-chip emulator capable of playing the original C64 files with acceptable quality. Of course you need a real SID for the full experience, in my oppinion (for details on the 6581 SID, see http://stud1.tuwien.ac.at/~e9426444/sidpage.html). You can find the homepage of SID Play at http://www.geocities.com/SiliconValley/Lakes/5147; to go directly to the OS/2 version by Peter Conklin, surf to http://sidplay.eaust.net.
'PSID' files are basically the original 6510 program code, prefixed with a small header providing necessary information for PlaySID (and compatibles) to replay the music. The header also contains song title, author and copyright. When you want to transfer a SID tune to 'PSID' this header must be added, which can be a bit tedious doing in a monitor/hex-editor when there are lots of tunes to transfer. This is the reason I wrote psidTool; I was in the process of converting all my own SID compositions to 'PSID', and decided to write this little tool to greatly ease the addition/manipulation of 'PSID' headers.