mu106sbn@sdcc13.ucsd.EDU (Stephen Hartford) (05/03/87)
[the line battle continues...]
In the April '87 issue of Keyboard magazine, Peter Gotcher
writes:
"... several developers writing software for the Amiga ..
have been unable to use the Amiga's high speed clock to time-
stamp incoming MIDI events (the clock starts and stops unpredict-
ably when it is interrupted by other processing tasks). The only
alternative is to use the Amiga's 60Hz video retrace to time
events, resulting in a timing accuracy of 16ms..."
This accuracy is not good enough for any serious MIDI recording /
sequencing. Is this the reason so little MIDI software is being
developed for the Amiga (vs. ST and Mac)? I've heard talk of a
MIDI card for the A2000 - is this card going to have a dedicated
high speed clock on it? SoundScape shows the kind of sophistica-
tion MIDI software is capable of having on the Amiga. It would be
a shame if developers shy away from future Amiga software because
of hardware limitations.
--
Stephen Hartford, programmer (a.k.a. student) ///
-- \\\///
Internet: mu106sbn%sdcc13@sdcsvax.ucsd.edu \///
UUCP: ...!sdcsvax!sdcc13!mu106sbn dillon@CORY.BERKELEY.EDU (Matt Dillon) (05/03/87)
>This accuracy is not good enough for any serious MIDI recording / >sequencing. Is this the reason so little MIDI software is being >developed for the Amiga (vs. ST and Mac)? I've heard talk of a Pooh. All three machines are 68000's. The problem is that the Amiga is multi-tasking, whereas the Mac and ST are basically single-tasking. Taking over the machine, though easily, is not as practical for the Amiga because there would then be many angery users giving the Co. hell for doing it. So what does the Amiga give the MIDI developer as an option? You got it... either add some hardware to generate an interrupt (adding your interrupt handler to the system), or futz around with the interrupts you've got from the serial and parallel ports. Since MIDI is serial, I see no reason why a MIDI developer couldn't write his own serial.device, and then he can do anything he wants with the serial interrupts. -Matt
chin-lon@puff.WISC.EDU (Chin-long Cheng) (05/03/87)
In article <8705030737.AA23966@cory.Berkeley.EDU>, dillon@CORY.BERKELEY.EDU (Matt Dillon) writes: > So what does the Amiga give the MIDI developer as an option? > You got it... either add some hardware to generate an interrupt (adding > your interrupt handler to the system), or futz around with the interrupts > you've got from the serial and parallel ports. Since MIDI is serial, I > see no reason why a MIDI developer couldn't write his own serial.device, > and then he can do anything he wants with the serial interrupts. > > -Matt You are absolutely right. As a matter of fact, adding your own sreial interrupt handler (Remember my previous posting concerning this?) and an interrupt handler to the 8520A timer solves all the timing problems, with the 8520A timer providing the timing needed for the serial interrupt handler. Currently, no extra hardware except a midi interface is needed. clc # ARPA: chin-lon@puff.wisc.edu # CSNET: chin-lon%puff.wisc.edu@csnet-relay # UUCP: ...!{ihnp4,hplabs,seismo,topaz,etc.}!uwvax!puff!chin-lon
doug@edge.UUCP (Doug Pardee) (05/06/87)
> It would be > a shame if developers shy away from future Amiga software because > of hardware limitations. Say what?? If the Amiga doesn't offer suitable hardware for some application, why on earth should a developer go with an Amiga? The cause and effect are backwards here. You don't say "I am going to use an Amiga to do this," and then say, "I wish Amigas had the features I need." You say, "I need this feature and this feature. The systems with those features are xxx and yyy, so I'll develop for one of those." Elsewise, one could say about color graphics, "It would be a shame if developers shy away from the Macintosh because of hardware limitations." -- Doug Pardee -- Edge Computer Corp., Scottsdale, AZ -- ...!ihnp4!mot!edge!doug
bryce@COGSCI.BERKELEY.EDU (Bryce Nesbitt) (05/09/87)
[eat me] In article <722@edge.UUCP> doug@edge.UUCP (Doug Pardee) writes: >> It would be >> a shame if developers shy away from future Amiga software because >> of hardware limitations. > >Say what?? > >If the Amiga doesn't offer suitable hardware for some application, why on >earth should a developer go with an Amiga? Two points: 1> This particular instance is *NOT* a hardware limitation. At worst it is a documentation lack. The needed high precision timer is available. It is *easy* to timestamp incomming MIDI events with *VERY* high precision. 2> To take a more general jab at what you said consider this; You plan to develop for a computer (any computer). Everything works out well, very well, except for this missing [fill in the blank]. -! There is always a place to wish for 'a little more' or to say 'if only'. -! Particularly if you like the base system to start out with. A developer considers many things before developing for a particular computer; hardware is one issue, Operating System another, installed base and buying habits a third. The IBM-PC should prove byond all doubt that spectacular hardware is not a hard fast prerequisite for third party support. Remember: IF THE HARDWARE RESOURCES THE BASE COMPUTER HAS ARE NOT ENOUGH, THEN YOU HAVE DISCOVERED A PERFECT EXAMPLE OF WHAT 'EXPANSION' CAN BE USED FOR. (Again -> this is not a problem for Amiga MIDI timestamping) [Eat Me]