Intel 80C188XL 3 LCS Active Range, CHIP-SELECTUNIT 6.4.2.2LCS Active Range, 4.MCS Active Range

CHIP-SELECT UNIT

6.4.2.2LCS 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.

Table 6.3 LCS Active Range

LMCS Field	Block Size	Ending Address
U17:10	(Kbytes)
00H	1	003FFH
01H	2	007FFH
03H	4	00FFFH
07H	8	01FFFH
0FH	16	03FFFH
1FH	32	07FFFH
3FH	64	0FFFFH
7FH	128	1FFFFH
FFH	256	3FFFFH

6.4.2.3MCS 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.

Table 6-4. MCS Active Range

	Chip-	Active Range
	Select	Start Address	Ending Address
		Base	Base + (1/4 block size –1)
	MCS0
		Base + 1/4 block size	Base + (1/2 block size –1)
MCS1
		Base + 1/2 block size	Base + (3/4 block size –1)
MCS2
		Base + 3/4 block size	Base + (block size – 1)
MCS3

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