參數(shù)資料
型號: MC68LC060RC66
廠商: Freescale Semiconductor
文件頁數(shù): 12/128頁
文件大小: 0K
描述: IC MPU 32BIT 66MHZ 206-PGA
標(biāo)準(zhǔn)包裝: 10
系列: M680x0
處理器類型: M680x0 32-位
速度: 66MHz
電壓: 3.3V
安裝類型: 通孔
封裝/外殼: 206-BEPGA
供應(yīng)商設(shè)備封裝: 206-PGA(47.25x47.25)
包裝: 托盤
Caches
5-10
M68060 USER’S MANUAL
MOTOROLA
5.5.3 Read Hit
On a read hit, the appropriate cache provides the data to the requesting pipe unit. In most
cases no bus transaction is performed, and the state of the cache line does not change.
However, when a writethrough read hit to a line containing dirty data occurs, the dirty line is
pushed and the cache line state changes to valid before the data is provided to the request-
ing pipe unit.
A snooped external read hit invaildates the cache line that is hit.
5.5.4 Write Hit
The cache controller handles processor writes that hit in the cache differently for
writethrough and copyback pages. For write hits to a writethrough page, the portions of the
cache line(s) corresponding to the size of the access are updated with the data, and the data
is also written to external memory. The cache line state does not change. A writethrough
access to a line containing dirty data results in the dirty line being pushed and then witten to
memory. If the access is copyback, the cache controller updates the cache line and sets the
D-bit for the line. An external write is not performed, and the cache line state changes to, or
remains in, the dirty state.
An alternate bus master can assert the SNOOP signal for a write that it initiates, which will
invalidate any corresponding entry in the internal cache.
5.6 CACHE COHERENCY
The MC68060 provides several different mechanisms to assist in maintaining cache coher-
ency in multimaster systems. Both writethrough and copyback memory update techniques
are supported to maintain coherency between the data cache and memory.
Alternate bus master accesses can reference data that the MC68060 may have cached,
causing coherency problems if the accesses are not handled properly. The MC68060
snoops the bus during alternate bus master transfers if SNOOP is asserted. Snoop hits
invalidate the cache line in all cases (read, write, long word, word, byte) for MOVE16 and
normal accesses. Since the processor may be accessing data in its caches even when it
does not have the bus, a snoop has priority over the processor, to maintain cache coher-
ency.
The snooping protocol and caching mechanism supported by the MC68060 requires that
pages shared with any other bus master be marked cachable writethrough or cache inhib-
ited (either precise or imprecise). This procedure allows each processor to cache shared
data for read access while forcing a processor write to shared data to appear as an external
write to memory, which the other processors can snoop. If shared data is stored in copyback
pages, cache coherency is not guaranteed.
Coherency between the instruction cache and the data cache must be maintained in soft-
ware since the instruction cache does not monitor data accesses. Processor writes that
modify code segments (i.e., resulting from self-modifying code or from code executed to
load a new page from disk) access memory through the data memory unit. Because the
instruction cache does not monitor these data accesses, stale data occurs in the instruction
相關(guān)PDF資料
PDF描述
MC68LC060ZU75 IC MPU 32BIT 68K 75MHZ 304-TBGA
MC68M360ZQ25VLR2 IC MPU QUICC 25MHZ 357-PBGA
MC68MH360CZQ25L IC MPU QUICC 25MHZ 357-PBGA
MC68P11E1CFNE2R IC MCU 8BIT 52-PLCC
MC68SEC000AA16R2 IC MPU 32BIT 16 MHZ 64-QFP
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
MC68LC060RC75 功能描述:微處理器 - MPU 32B W/ CACHE MMU RoHS:否 制造商:Atmel 處理器系列:SAMA5D31 核心:ARM Cortex A5 數(shù)據(jù)總線寬度:32 bit 最大時鐘頻率:536 MHz 程序存儲器大小:32 KB 數(shù)據(jù) RAM 大小:128 KB 接口類型:CAN, Ethernet, LIN, SPI,TWI, UART, USB 工作電源電壓:1.8 V to 3.3 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:FBGA-324
MC68LC060ZU50 功能描述:微處理器 - MPU 32B W/ CACHE MMU RoHS:否 制造商:Atmel 處理器系列:SAMA5D31 核心:ARM Cortex A5 數(shù)據(jù)總線寬度:32 bit 最大時鐘頻率:536 MHz 程序存儲器大小:32 KB 數(shù)據(jù) RAM 大小:128 KB 接口類型:CAN, Ethernet, LIN, SPI,TWI, UART, USB 工作電源電壓:1.8 V to 3.3 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:FBGA-324
MC68LC060ZU66 功能描述:微處理器 - MPU 32B W/ CACHE MMU RoHS:否 制造商:Atmel 處理器系列:SAMA5D31 核心:ARM Cortex A5 數(shù)據(jù)總線寬度:32 bit 最大時鐘頻率:536 MHz 程序存儲器大小:32 KB 數(shù)據(jù) RAM 大小:128 KB 接口類型:CAN, Ethernet, LIN, SPI,TWI, UART, USB 工作電源電壓:1.8 V to 3.3 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:FBGA-324
MC68LC060ZU75 功能描述:微處理器 - MPU 32B W/ CACHE MMU RoHS:否 制造商:Atmel 處理器系列:SAMA5D31 核心:ARM Cortex A5 數(shù)據(jù)總線寬度:32 bit 最大時鐘頻率:536 MHz 程序存儲器大小:32 KB 數(shù)據(jù) RAM 大小:128 KB 接口類型:CAN, Ethernet, LIN, SPI,TWI, UART, USB 工作電源電壓:1.8 V to 3.3 V 最大工作溫度:+ 85 C 安裝風(fēng)格:SMD/SMT 封裝 / 箱體:FBGA-324
MC68LC302AF16CT 功能描述:數(shù)字信號處理器和控制器 - DSP, DSC 68K INTGR COM PROC, DMA RoHS:否 制造商:Microchip Technology 核心:dsPIC 數(shù)據(jù)總線寬度:16 bit 程序存儲器大小:16 KB 數(shù)據(jù) RAM 大小:2 KB 最大時鐘頻率:40 MHz 可編程輸入/輸出端數(shù)量:35 定時器數(shù)量:3 設(shè)備每秒兆指令數(shù):50 MIPs 工作電源電壓:3.3 V 最大工作溫度:+ 85 C 封裝 / 箱體:TQFP-44 安裝風(fēng)格:SMD/SMT