Aopen ak77proa133 用户手册
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7
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A memory space in Flash-ROM to simulate E
2
PROM operation, AOpen motherboard uses Shadow E
2
PROM for jumper-less and
battery-less design
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SIMM socket is only 72-pin, and is only single side. The golden finger signals on each side of PCB are identical. That is why it
DRAM and supports 32-bit data. SIMM had been phased out on
current motherboard design.
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SMBus is also called I2C bus. It is a two-wire bus developed for component communication (especially for semiconductor IC).
For example, set clock of clock generator for jumper-less motherboard. The data transfer rate of SMBus is only 100Kbit/s, it
allows one host to communicate with CPU and many masters and slaves to send/receive message.
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SPD is a small ROM or
device resided on the
. SPD stores memory module information such as DRAM
timing and chip parameters. SPD can be used by
to decide best timing for this DIMM or RIMM.