mende@shire.decnet (04/11/86)
From: "SHIRE::MENDE" <mende@shire.decnet>
Hello,
I am an active participent on a BBS here at rutgers and today I got
a few questions that I dont know the answer to. If anyone out there knows
the answers to them, please reply to me via mail.
What are the synthesizer abilities of the Amiga?
Does it have 4 or 6 parameter envelope generator?
What are the basic waveforms?
Does it come with complex waveform generation by additive
harmonic synthesis?
What type of MIDI data does it handle.
Can it cope with being connected to a sync unit e.g. KS-30?
Bob Mende
Snail: BPO 20187 ARPA : MENDE@AIM.RUTGERS.EDU
Piscataway NJ UUCP : seismo!topaz!aim!mende
08854 Phone: (201) 878-0602
CMS : rutgers!mende
_____________________________________________________________________________
[ I hereby disclaim that I exist and therefore proclam by default that the ]
[ proceding drivel is no more than a figment of your imagination ]
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------sam@amiga.UUCP (Samuel C. Dicker) (04/15/86)
In article <1781@caip.RUTGERS.EDU> mende@shire.decnet writes: > What are the synthesizer abilities of the Amiga? Hardware: --------- The Amiga has four 8 bit D/A converters. Each D/A has a programmable (by the 68000) volume and sampling rate (period) control. They are wired into 2 low-pass filters for the left and right stereo channels. Each D/A converter can be loaded by the 68000 or by it's own DMA channel. Each audio DMA channels can be used either to feed samples to it's D/A converter or to set the volume and/or period of another D/A converter. The DMA channels automatically restart at the end of the buffer. +---------------+ | | +---------------+ | CHANNEL 0 D/A |------+ | CHANNEL 0 DMA |-->O..__O-->|data | | +---------------+ +---------------+ | O | \ +---------------+ | +----------+ `--->|vol&per | V | LEFT | +---------------+ | CHANNEL 1 D/A |--+ +-->| LOW-PASS |--> L OUT | CHANNEL 1 DMA |-->O..__O-->|data | | ^ | FILTER | +---------------+ +---------------+ | | +----------+ O | | \ +---------------+ | | +----------+ `--->|vol&per | V | | RIGHT | +---------------+ | CHANNEL 2 D/A |->+-- | ->| LOW-PASS |--> R OUT | CHANNEL 2 DMA |-->O..__O-->|data | | | FILTER | +---------------+ +---------------+ | +----------+ O | \ +---------------+ | `--->|vol&per | | +---------------+ | CHANNEL 3 D/A |------+ | CHANNEL 3 DMA |-->O..__O-->|data | +---------------+ +---------------+ O \ `-- not used specs: DMA channels - addressing range: 0 thru 0x7FFFF (word aligned) buffer size range: 2 thru 131072 samples (even) maximum rate: 28867.3 samples per second D/A converters - amplitude range: -128 thru 127 amplitude accuracy: < 1/2 least significant bit sampling rate range: 279.365 ns thru 18.3085 ms sampling rate resolution: 279.365 ns volume control range: 0 thru 64 linear low-pass filters- slope: 6 pole, 36db/octave pass band response: + or - 3db 15Hz thru 4kHz stop band response: -40db at 7kHz Software: --------- ROM kernal audio is an exec device. Commands include allocation and arbitration (prioritized stealing) of channels, and DMA channel control. > Does it have 4 or 6 parameter envelope generator? Envelopes are generated by the application software and can have any number of parameters or a custom envelope table lookup. > What are the basic waveforms? Anything you want. :-) > Does it come with complex waveform generation by additive > harmonic synthesis? The audio device (in the ROM kernal) supports but does not provide any type of synthesis. I would be glad to answer any question about how to do any (your favorite) type of synthesis on the Amiga. > What type of MIDI data does it handle. The serial port on the Amiga can be set to run at MIDI rate (31250 baud) and with a little level conversion, opto-isolation and buffering the Amiga can send and receive MIDI; however, no MIDI driver is provided in the ROM kernal. Sam Dicker {decwrl|hplabs}!pyramid!amiga!sam
ins_adjb@jhunix.UUCP (Daniel Jay Barrett) (04/17/86)
> In article <1781@caip.RUTGERS.EDU> mende@shire.decnet writes: > > > What are the synthesizer abilities of the Amiga? > > Does it come with complex waveform generation by additive > > harmonic synthesis? > The audio device (in the ROM kernal) supports but does not provide any type > of synthesis. I would be glad to answer any question about how to do any > (your favorite) type of synthesis on the Amiga. > Sam Dicker > {decwrl|hplabs}!pyramid!amiga!sam OK, I'll bite: how can you do: 1) Additive synthesis 2) FM synthesis ?? Dan Barrett
local-info-amiga-request@ics.UCI.EDU (04/21/86)
From: Daniel Jay Barrett <jhunix!ins_adjb@caip.rutgers.edu> > In article <1781@caip.RUTGERS.EDU> mende@shire.decnet writes: > > > What are the synthesizer abilities of the Amiga? > > Does it come with complex waveform generation by additive > > harmonic synthesis? > The audio device (in the ROM kernal) supports but does not provide any type > of synthesis. I would be glad to answer any question about how to do any > (your favorite) type of synthesis on the Amiga. > Sam Dicker > {decwrl|hplabs}!pyramid!amiga!sam OK, I'll bite: how can you do: 1) Additive synthesis 2) FM synthesis ?? Dan Barrett