21285-AB Sdram And Rom Operation - Intel Corporation
Manufacturer Part Number
Microprocessor, 21285 Core Logic For SA-110 Microprocessor
Specifications of 21285-AB
SDRAM and ROM Operation
This chapter describes the operation of the SDRAM and ROM.
The SDRAM controller on the 21285 controls from one to four arrays of synchronous DRAMs
(SDRAMs). SDRAM supported parts include: 8Mb, 16Mb, and 64Mb.
All SDRAMs share command and address bits, but have separate clock and chip select bits (see
Figure 4-1. SDRAM Configuration
When SA-110 reads or writes SDRAM,
the data does not pass through 21285.
SDRAM operations performed by the 21285 are refresh, read, write, and mode register set. Reads
and writes are generated by either the SA-110, PCI bus masters (including I
21285 Core Logic for SA-110 Datasheet
O accesses), or DMA