Re: Ensoniq Question

[David.Empson@bbs.actrix.gen.nz]

In article <mbusse.0xc4@amiganet.chi.il.us> mbusse@amiganet.chi.il.us (Marco Busse) writes:
>
> [wave tables must be aligned to a boundary that corresponds to their size]
>
> I can't say that I have read confirmation of this anywhere (it doesn't - as far
> as I know - specifically say this in the Hardware Ref. or any other reference
> books I have). Has anyone else?

I can't spot anything that explicitly says this, but if you look at
the table which explains how the address is calculated, you can see
that less bits of the wavetable pointer register are used for large
table sizes.

For a 32k wave table, one bit is used (32k alignment - bit 15).
For a 16k wave table, two bits are used (16k alignment - bits 15-14).
...
For a 256 byte wave table, eight bits are used (256 byte alignment -
bits 15-8).

In the 2nd edition of the hardware ref, this is Figure 5-7 (Final
address calculation in the Wavetable Size register) on page 116.

> 
> _____________________________________________________________________________
> Marco Busse                    | "True dignity is never gained by place,
> Jupiter Systems                |  And never lost when honors are withdrawn."
> mbusse@amiganet.chi.il.us      |
> Apple II Infinitum             |                        -Massinger


-- 
David Empson

Internet: David.Empson@bbs.actrix.gen.nz    EMPSON_D@kosmos.wcc.govt.nz
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