Mirage-Freq

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Requirements: Commodore 64 or 128, Passport Designs or Sequential Circuits MIDI i/f, Ensoniq Mirage running MASOS 2.0

Mirage-Freq is a program that runs on a C=64. It was featured in a two-part article in the Transoniq Hacker in the April and May '93 issues. The program generates tones that very accurately match in pitch, the sample rate the Mirage is currently set to. The program reads the current sample rate, and uses either the onboard SID chip or MIDI to generate a tone.

The purpose for all of this is to get pitches that can be sampled with an exact number of waves per page. This allows short loops to very closely match the pitch of the non-looped portion of a sound. A more detailed explanation is available.

Since this is useful to folks who run on platforms other than the C=64, I've made ASCII source available as well.

C= 64 Sources

The entire package is available for download as an lharc archive file. The individual components are also available for reading/downloading: The Self-Dissolving Archive, when run on a C=64 (or C=128 in 64 mode) will break itself into the various files, including the BASIC and assembly language programs, and an additional MOREINFO program that provides a short tutorial on sampling and using MirageFreq.

ASCII Source

If you're not running on a C=64 (and who is these days?), you still might like to look at the source. Most of it is in Commmodre Basic with a short 6502 assembly routine to handle getting the sample rate from the Mirage. You can download the entire package as an lharc archive file or read/download the pieces:

Page created by Johnny Klonaris, 13 Nov 95