
 MOTOROLA
36
M68HC11 K Series
MC68HC11KTS/D
Figure 7 Memory Expansion Example 1
This example is a system consisting of the MCU, a single 27C512-type memory device as in the previ-
ous example, and two 6226-type memory devices as well. This system uses two chip selects and has
two windows. For purposes of explanation, the setup of the first window is identical to the previous ex-
ample. In addition, a second window consisting of 16 banks of 16 Kbytes each uses the second chip
select signal. Window 1 contains 64 Kbytes of expanded memory pages, window 2 contains a total of
256 Kbytes of expanded memory. A total of five expansion address lines are used. Register values par-
ticular to this example are given below the diagram. 
$0000
$1000
$4000
$6000
$00000
$01FFF
$02000
$03FFF
$04000
$05FFF
$06000
$07FFF
$08000
$09FFF
$0A000
$0BFFF
$0C000
$0DFFF
$0E000
$0FFFF
INTERNAL
EPROM
CHIP SELECT 1
$FFFF
WINDOW 1
BANK 0
BANK 1
BANK 2
BANK 3
BANK 4
BANK 5
BANK 6
BANK 7
0:0:0
0:0:1
0:1:0
0:1:1
1:0:0
1:0:1
1:1:0
1:1:1
XA[15:13]=
XA[15:13]=
XA[15:13]=
XA[15:13]=
XA[15:13]=
XA[15:13]=
XA[15:13]=
XA[15:13]=
PGAR = $07
MMWBR = $04
MMSIZ = $41
XA[15:13]
WINDOW 1 @ $4000,
WINDOW 2 DISABLED
WINDOW 1 = 8 KBYTES,
WINDOW 2 DISABLED
NO I/O OR PROGRAM CHIP SELECTS
GEN. PURPOSE CHIP SELECT 1 FROM $00000
64 KBYTE RANGE (8 X 8K)
N/A
GEN. PURPOSE CHIP SELECT 2 DISABLED
CSCTL = $00
GPCS1A = $00
GPSC1C = $06
GPCS2A = $00
GPCS2C = $00
$A000