參數(shù)資料
型號(hào): DS89C450-KIT#
廠商: Maxim Integrated Products
文件頁(yè)數(shù): 19/46頁(yè)
文件大小: 0K
描述: KIT MCU FLASH ULTRA HIGH SPEED
產(chǎn)品培訓(xùn)模塊: Lead (SnPb) Finish for COTS
Obsolescence Mitigation Program
標(biāo)準(zhǔn)包裝: 1
類型: MCU
適用于相關(guān)產(chǎn)品: DS89C450
所含物品:
其它名稱: 90-89450#KIT
DS89C430/DS89C450 Ultra-High-Speed Flash Microcontrollers
26 of 46
External Memory
The DS89C430 executes external memory cycles for code fetches and read/writes of external program and data
memory. A nonpage external memory cycle is four times slower than the internal memory cycles (i.e., an external
memory cycle contains four system clocks). However, a page mode external memory cycle can be completed in
one, two, or four system clocks for a page hit and two, four, or eight system clocks for a page miss, depending on
user selection. The DS89C430 also supports a second page mode operation with a different external bus structure
that provides for fast external code fetches but uses four system clock cycles for data memory access.
External Program Memory Interface (Nonpage Mode)
Figure 7 shows the timing relationship for internal and external code fetches when CD1 and CD0 are set to 10b,
assuming the microcontroller is in nonpage mode for external fetches. Note that an external program fetch takes
four system clocks, and an internal program fetch requires only one system clock.
As illustrated in Figure 7, ALE is deasserted when executing an internal memory fetch. The DS89C430 provides a
programmable user option to turn on ALE during internal program memory operation. ALE is automatically enabled
for code fetch externally, independent of the setting of this option.
PSEN
is only asserted for external code fetches, and is inactive during internal execution.
Figure 7. External Program Memory Access (Nonpage Mode, CD1:CD0 = 10)
Internal Memory Cycles
C2
C3 C4
C1
C2
C3
C4
XTAL1
ALE
Port 0
Port 2
PSEN
C1
External Memory Cycle
MSB Add
LSB Add
Data
LSB Add
Data
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相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
DS89C450-KIT# 功能描述:開發(fā)板和工具包 - 8051 Ultra-High-Speed Flash MCU RoHS:否 制造商:Silicon Labs 產(chǎn)品:Development Kits 工具用于評(píng)估:C8051F960, Si7005 核心: 接口類型:USB 工作電源電壓:
DS89C450-MNG 功能描述:8位微控制器 -MCU Ultra-High-Speed Flash MCU RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時(shí)鐘頻率:50 MHz 程序存儲(chǔ)器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
DS89C450-MNG+ 功能描述:8位微控制器 -MCU Ultra-High-Speed Flash MCU RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時(shí)鐘頻率:50 MHz 程序存儲(chǔ)器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
DS89C450-MNL 功能描述:8位微控制器 -MCU Ultra-High-Speed Flash MCU RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時(shí)鐘頻率:50 MHz 程序存儲(chǔ)器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT
DS89C450-MNL+ 功能描述:8位微控制器 -MCU Ultra-High-Speed Flash MCU RoHS:否 制造商:Silicon Labs 核心:8051 處理器系列:C8051F39x 數(shù)據(jù)總線寬度:8 bit 最大時(shí)鐘頻率:50 MHz 程序存儲(chǔ)器大小:16 KB 數(shù)據(jù) RAM 大小:1 KB 片上 ADC:Yes 工作電源電壓:1.8 V to 3.6 V 工作溫度范圍:- 40 C to + 105 C 封裝 / 箱體:QFN-20 安裝風(fēng)格:SMD/SMT