MPC8280 datasheet(529/1386 Pages) FREESCALE

부품명	MPC8280

상세설명	PowerQUICC??II Family Reference Manual

PDF	1386 Pages

Scroll/Zoom	100%

제조업체	FREESCALE [Freescale Semiconductor, Inc]

홈페이지	http://www.freescale.com

Logo

529 / 1386 page

Secondary (L2) Cache Support

MPC8280 PowerQUICC II Family Reference Manual, Rev. 1

Freescale Semiconductor

12-3

and its associated latency. Thus, reads are serviced just as they are for copy-back mode. Write-through

mode sacrifices some of the write performance of copy-back mode, but guarantees L2 cache coherency

with main memory.

Since write-through mode keeps memory coherent with the contents of the L2 cache, there is never any

need to perform an L2 copy-back. This removes the need for the L2 cache to maintain a dirty bit in the tag

RAM (all cache blocks are unmodified) and it also removes the need for bus arbitration signals.

The L2 cache is configured for write-through mode by pulling down it’s WT signal. There are no

configuration changes to the MPC8280 required in write-through mode. The MPC8280 can also support

additional bus masters (60x or MPC8280-type) in write-through mode.

Figure 12-2 shows a MPC8280 connected to a MPC2605 integrated L2 cache in write-through mode.

MPC8280 데이터시트(PDF) 529 Page - Freescale Semiconductor, Inc