Commodore 128 Programmer's Reference Manual page 53

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BASIC BUILDING BLOCKS AND BASIC 7.0 ENCYCLOPEDIA 43
FAST
H Sets the 8502 microprocessor at a speed of 2MHz.
FAST
p This command initiates 2MHz mode, causing the VIC 40-column screen to be turned off.
j } All operations are speeded up considerably. Graphics may be used, but will not be visible
until a SLOW command is issued. The Commodore 128 powers up in 1MHz mode. The
DMA operations (FETCH, SWAP, STASH) must be performed at 1MHz (slow) speed.
FETCH
Get data from expansion (RAM module) memory
FETCH #bytes, intsa, expsa, expb
where bytes = Number of bytes to get from expansion memory (0-65535) where 0 =
64K (65535 bytes)
intsa = Starting address of host RAM (0-65535)
expb = 64K expansion RAM bank number (0-7) where expb = 0-1 for 128K
and expb = 0-7 for up to 512K.
expsa = Starting address of expansion RAM (0-65535)
The host BANK for the ROM and I/O configuration is selected with the BANK
command. The DMA(VIC) RAM bank is selected by bits 6 and 7 of the RAM
configuration register within the MMU($D506).
FILTER
Define sound (SID chip) filter parameters
FILTER [freq][,Ip] [,bp] [,hp] [,res]
where:
freq Filter cut-off frequency (0-2047)
lp Low-pass filter on (1), off (0)
bp Band-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.
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.