MOTOROLA
MC68HC11F1/FC0
40
MC68HC11FTS/D
PCSEN — Program Chip-Select Enable
Reset clears PCSEN in single-chip modes and sets PCSEN in expanded modes.
0 = CSPROG disabled
1 = CSPROG enabled
PSIZA, PSIZB — Select Size of Program Chip-Select
GA[15:10] — General-Purpose Chip-Select Starting Address
These bits determine the starting address of the CSGEN valid address space and correspond to the
high-order address bits ADDR[15:10]. Table 19 illustrates how the block size selected determines
which of this register's bits are valid.
Bits [1:0] — Not implemented. Reads always return zero and writes have no effect.
IO1AV — I/O Chip-Select 1 Address Valid
0 = CSIO1 is valid during E-clock valid time (E-clock high)
1 = CSIO1 is valid during address valid time
IO2AV — I/O Chip-Select 2 Address Valid
0 = CSIO2 is valid during E-clock valid time (E-clock high)
1 = CSIO2 is valid during address valid time
Table 18 Program Chip Select Size Control
PSIZA
PSIZB
Size
Address Range
0
0
64 Kbytes
$0000–$FFFF
0
1
32 Kbytes
$8000–$FFFF
1
0
16 Kbytes
$C000–$FFFF
1
1
8 Kbytes
$E000–$FFFF
CSGADR — General-Purpose Chip-Select Address Register
$x05E
Bit 7
6
5
4
3
2
1
Bit 0
GA15
GA14
GA13
GA12
GA11
GA10
—
—
RESET:
0
0
0
0
0
0
0
0
Table 19 General Purpose Chip Select Starting Address
CSGEN Block Size
CSGADR Bits Valid
0 Kbytes
None
1 Kbyte
GA15 – GA10
2 Kbytes
GA15 – GA11
4 Kbytes
GA15 – GA12
8 Kbytes
GA15 – GA13
16 Kbytes
GA15 – GA14
32 Kbytes
GA15
64 Kbytes
None
CSGSIZ — General-Purpose Chip-Select Size Register $x05F
Bit 7
6
5
4
3
2
1
Bit 0
IO1AV
IO2AV
—
GNPOL
GAVLD
GSIZA
GSIZB
GSIZC
RESET:
0
0
0
0
0
1
1
1