Commodore 128 Programmer's Reference Manual page 462

452 COMMODORE 128
13. $FF6B GETCFG ;lookup MMU data for given bank
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PREPARATION:
Registers:
Memory:
Flags:
Calls:
RESULTS:
Registers:
Memory:
Flags:
EXAMPLE:
LDX #$00
JSR $FF6B
STA $FF01
.X = logical bank # (0-15)
system map
none
none
.A = MMU configuration data
none
none
;logical bank 0 (RAM 0)
;GETCFG
;setup MMU pre-config #1
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GETCFG allows a universal, logical approach to physical bank numbers by
providing a simple lookup conversion for obtaining the actual MMU configuration
data. In all cases where a bank number 0-15 is required, you can expect GETCFG
to be called to convert that number accordingly. There is no error checking; if the
given logical bank number is out of range the result is invalid. Refer to the Memory
Management Unit in the Commodore 128 section later in this chapter for details concern
ing memory configuration. The C128 Kernal memory banks are assigned as follows:
0.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
%00111111
%01111111
%10111111
%11111111
%00010110
%01010110
%10010110
%11010110
%00101010
%01101010
%10101010
%11101010
%00000110
%00001010
%00000001
%00000000
:RAM 0 only
:RAM 1 only
:RAM 2 only
:RAM 3 only
:INTROM, RAM
:INTROM, RAM
:INTROM, RAM
:INTROM, RAM
:EXT ROM, RAM
:EXT ROM, RAM
:EXT ROM, RAM
:EXT ROM, RAM
0, I/O
1,1/0
2,1/0
3,1/0
0, I/O
1,1/0
2,1/0
3,1/0
:KERNAL, INT LO, RAM
:KERNAL, EXT LO, RAM
:KERNAL, BASIC
:KERNAL, BASIC
, RAM
, RAM
0, I/O
O.I/O
0, CHAR ROM
0, I/O
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