Intel 386 User Manual page 441

Intel386™ EX EMBEDDED MICROPROCESSOR USER'S MANUAL
Example 2
This example establishes four 4-Kbyte address blocks starting at 0000000H, 0002000H,
0004000H, and 0006000H (4-Kbyte boundaries).
15-bit Channel Address
15-bit Channel Mask
Channel Active Address
Because the least-significant 0 in the channel's mask is in bit position 2, this channel's active ad-
2
dress block size is 2 = 4 Kbytes. Because there are two 1's to the left of the right-most 0 in the
channel's mask, the block is repeated 2
mask where there are 1's in the channel address, the channel address is the starting address of the
lowest active address block. In this example, each active 4-Kbyte address block in memory is fol-
lowed by an inactive 4-Kbyte address block and each active address block starts on a 4-Kbyte
address boundary.
14-6
15
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 1 1 0 1
25
0 0 0 0 0 0 0 0 0 0 0 X X 0 X
2
= 4 times. Also, because there are no 1's in the channel
Memory Address
0007000H
Active 0006FFFH
0006000H
0005FFFH
0005000H
Active 0004FFFH
0004000H
0003FFFH
0003000H
Active 0002FFFH
0002000H
0001FFFH
0001000H
Active 0000FFFH
0000000H
1
X X X X X X X X X X X
Maximum
0