Lcs Active Range - Intel 80C186EA User Manual

6.4.2.2

LCS Active Range

The LCS starting address is fixed at zero in memory address space; its ending address is the pro-
grammed block size minus one. Table 6.3 defines the acceptable values for the field (U17:10) in
the LMCS register that determines the LCS block size and ending address.
LMCS Field
U17:10
00H
01H
03H
07H
0FH
1FH
3FH
7FH
FFH
6.4.2.3 MCS Active Range
The starting and ending addresses of the individual MCS chip-selects are determined by the base
address programmed in the MMCS register and the block size programmed in the MPCS register
(see Table 6-4 and Figure 6-10). The base address must be an integer multiple of the block size.
Table 6-5 lists the allowable block sizes and base address limitations.
Chip-
Select
MCS0
MCS1
MCS2
MCS3
Table 6.3 LCS Active Range
Block Size
(Kbytes)
1
2
4
8
16
32
64
128
256
Table 6-4. MCS Active Range
Active Range
Start Address
Base Base + (1/4 block size –1)
Base + 1/4 block size Base + (1/2 block size –1)
Base + 1/2 block size Base + (3/4 block size –1)
Base + 3/4 block size Base + (block size – 1)
CHIP-SELECT UNIT
Ending Address
003FFH
007FFH
00FFFH
01FFFH
03FFFH
07FFFH
0FFFFH
1FFFFH
3FFFFH
Ending Address
6-13