Re: Moving binary files to /RAM

["GarberStreet" <willy46pa@comcast.net>]

"Laine Houghton" <laine@intergate.com> wrote in message
10vr1sftgit59c6@corp.supernews.com">news:10vr1sftgit59c6@corp.supernews.com...
:
: "Simon Williams" <email@DELETE_THIS.luddite.no-ip.com> wrote in message
: news:1gr5zon.d2hs7hoiep0yN%email@DELETE_THIS.luddite.no-ip.com...
: > On a tangent, but still related:
: >
: > Just so you know why this matters, I'll explain what I'm up to: I'm
: > trying to put together another drum sequencing program using DAC522 a la
: > TIMELORD. I thought that by using /RAM to store the samples I could make
: > use of more/bigger samples thus extending the programs capabilities
: > however:
: >
: > I have 16 samples named "A"..."P", each 3072 bytes copied to
: > /RAM/SAMPLES/
: >
: > I'm using this code to play them in order:
: >
: > 160 FOR F = 65 TO 80
: > 170 PRINT CHR$(4)"BLOAD /RAM/SAMPLES/" CHR$(F) ",A$2000"
: > 180 CALL 35840 : REM DAC522
: > 190 NEXT F
: >
: > What happens, oddly enough, is that the first 12 samples play
: > back-to-back as one would hope, but then there is a noticeable delay
: > between the last four. I've tried this on a IIe, IIgs and IIc+ with the
: > same result...
: >
: > Any ideas...?
:
:  I did a test saving  blocks of 1's 2's 3's......... 3072 bytes just as
the
: program would do. The 12's representing the 12'th file ends right at $BFFF
: The 13'th to 16'th files would be contained in the bank 1 bank 2 and
beyond
: memory.
:
: I'm guessing that the bank switching overhead introduces an unavoidable
: delay that a program such as yours is sensative to.
:
: A good incentive to get down to the assy work. With a 1 meg card you could
: move 12 files worth of samples to successive 64k banks.
:
: If I did my napkin math correctly that would be 180 files and it should
work
: as smooth as the 12 alone.
:
: Laine...

My suggestion would be to try moving the first 3072 into memory
at one location and start playing, then while playing, move second
3072 into another part of ram at another location, then alternate
them until all of the sections are played. Would this work, and also
would it solve the problem?

Apple II Forever, and Apple II Together,
Bill @ GarberStreet Enterprizez };-)
Web Site - http://garberstreet.netfirms.com
Email - willy46pa@comcast.net