Commodore 128D User Manual page 273

H
FETCH
i i
n
FILTER
—Get data from expansion (RAM module) memory
NOTE: This command can only be used with a RAM expansion
module.
FETCH #bytes, intsa, expsa, expb
where bytes = number of bytes to get from expansion memory
(1-65536)
intsa = starting address of host ram (0-65535)
expb ;= 64k expansion RAM bank number
(0-1.) 1700 RAM expander
(0-7) 1750 RAM expander
expsa = starting address of expansion RAM (0-65535)
The host BANK is selected with the BANK command.
The number of expansion RAM banks is determined by the RAM
module.
NOTE: You must select SLOW (1 MHz) mode before using this com
mand. You may restore FAST mode after using this command. For
more information see your RAM expander manual.
—Define sound filter parameters
FILTER [freq] [,[lp] [,[bp] [,[hp] [,reslffl
where:
freq Filter cut-off frequency (0-2047)
Ip Low-pass filter on (1), off (0)
bp Bank-pass filter on (1), off (0)
hp High-pass filter on (1), off (0)
res Resonance (0-15)
Unspecified parameters result in no change to the current value.
You can use more than one type of filter at a time. For example, both
low-pass and high-pass filters can be used together to produce a
notch-(or band-reject) filter response. For the filter to have an audible
effect, at least one type of filter must be selected and at least one
voice must be routed through the filter.
EXAMPLES:
FILTER 1024,0,1,0,2 Set the cutoff frequency at 1024,
select the band pass filter and a
resonance level of 2.
FILTER 2000,1,0,1,10 Set the cutoff frequency at 2000,
select both the low pass and high
pass filters (to form a notch reject)
and set the resonance level at 10.
265
BASIC 7.0 ENCYCLOPEDIA—Basic Commands and Statements