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8-bit bus, is located in this area.
makes the video I/O sluggish.
this space into the 16 bit system board RAM. The EGA/VGA bios can be copied in
the 16-bit RAM and executed from there.
since the EGA BIOS can now be accessed through a 16-bit bus.
then memory address 0C0000 through 0DFFFF cannot be accessed on the 16-bit I/O
slot. Also, any I/O slot 8-bit memory in that space will be automatically
disabled.
DRAM access
In 80386SX, a zero wait-state bus cycle requires two clock cycles.
required
number
introduced in the access.
To speed up the memory reads, the AMI-386SX incorporates a page interleave
scheme. This improves system speed, since a page hits requires no wait states,
whereas a normal memory access would require wait states to be inserted.
Data Access: Cycle times
Table 3.1 gives the wait states and total bus cycle times for different cases
of on-board DRAM access:-
The AMI-386SX provides the option of mapping
of
clock
cycles
Most processor accesses are memory read operations.
The slow execution of this device driver
This improves the video I/O speed,
increases
by
one
When this is done
with
every
wait-state
The
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