AR-B1476 User
’
s Guide
3-12
3.2.13 Memory Setting
(1) DRAM Configuration
There are two 32-bit memory banks on the AR-B1476 board. It can be one-side or double-side SIMM (Single-Line
Memory Modules) which is designed to accommodate 256KX36 bit to 16MX36-bit SIMMs. This provides the user
with up to 64MB of main memory. The 32-bit SIMM (without parity bit) also can be used on AR-B1476 board.
There are listing on-board memory configurations available. Please refer to the following table for details:
SIMM1 Total
Memory
256KX32(X36) 1MB
512KX32(X36) 2MB
1MX32(X36) 4MB
2MX32(X36) 8MB
4MX32(X36) 16MB
8MX32(X36) 32MB
16MX32(X36) 64MB
Table 3-7 DRAMs’ Configuration
(2) Cache RAM (JP1)
The AR-B1476 can be configured to provide a write-back or write-through cache scheme and support 512KB
cache systems. A write-back cache system may provide better performance than a write-through cache system.
The BIOS Setup program allows you to set the cache scheme either write-back or write-through, either the internal
cache selection.
JP1
1
2
Factory Default Setting
JP1
1
2
Write-Through
Write-Back
Figure 3-28 JP1: Write-Through/Write-Back CPU Select
(3) Cache Size Select (CP1)
The CP1 is located on the back of CPU card. The factory setting is fixed is 512K Byte, this function can’t be
supplied for user adjusting. The type of setting’s table is in following.
CP1
Data RAM
TAG RAM
SIZE
OPEN
four 64K x 8
32K x 8
256KB
CLOSE
four 128K x 8
32K x 8
512KB
Table 3-8 Cache Size Selected
