Specifications

Built-in BIOS Setup Program
• BUSCLK Selection
The BUSCLK Selection is an output clock for the I/O channel. This field
used to specify the I/OBUSCLK clcok source used by the system. The user
does not need to change this settings.
The available options are listed below:
. 7.159MHz
. CPUCLK/2 (is recommended for 16 & 20 MHz)
• CPUCLK/2.5
. CPUCLK/3 (is recommended for 25 MHz)
. CPUCLK/4 (is recommended for 22 MHz)
. CPUCLK/5
• CPUCLK/6 (is recommended for 50 MHz)
. CPUCLK/8
• Non-Cacheable Area 1/2
In some applications, users desire a block of memory not to be cached. The
mainboard provids two programmable non-cacheable regions to serve this
function. The memory residing on the AT add-on is non-cacheable. When a
memory space is mapped by both the on-board DRAM and AT add-on
memory, CPU access will be conducted to the on-board DRAM. If users
desire the AT add-on memory to be accessed instead of the on-board DRAM
at the overlapped memory space, the two non-cacheable regions can be used
to disable the on-board DRAM in the proagrammed space.
H Non-Cacheable Area 1/2 Size
For some special I/O cards which need to use system memory, you should
reserve some memory space for use. The size of the Non-Cacheable Area
1/2 can be as small as 64KB or as large as 4MB. The Non-Cacheable Area
1/2 Start is set to be "Disabled" as default value.
• Non-Cacheable Area 1/2 Start
This function is to set the address of Non-Cacheable Area 1/2 from starting.
• C000 Shadow RAM Cacheable
If you have a shadowing of the video BIOS at C000 Shadow RAM, you can
enable this memory cacheable.
• FOOO Shadow RAM Cacheable
If you have a shadowing of the system BIOS, you can enable this option for
memory cacheable function.
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