參數(shù)資料
型號(hào): DS80C320-ECG
廠商: DALLAS SEMICONDUCTOR
元件分類: Microcontroller
英文描述: 8-BIT, MROM, 25 MHz, MICROCONTROLLER, PQFP44
封裝: TQFP-44
文件頁數(shù): 3/42頁
文件大?。?/td> 736K
代理商: DS80C320-ECG
DS80C320/DS80C323
11 of 42
On reset, the Stretch value will default to a 1, resulting in a three-cycle MOVX. Therefore, RAM access
will not be performed at full speed. This is a convenience to existing designs that may not have fast RAM
in place. When maximum speed is desired, the software should select a Stretch value of 0. When using
very slow RAM or peripherals, a larger stretch value can be selected. Note that this affects data memory
only and the only way to slow program memory (ROM) access is to use a slower crystal.
Using a Stretch value between 1 and 7 causes the microcontroller to stretch the read/write strobe and all
related timing. This results in a wider read/write strobe allowing more time for memory/peripherals to
respond. The timing of the variable speed MOVX is shown in the Electrical Specifications. Note that full
speed access is not the reset default case. Table 3 below shows the resulting strobe widths for each
Stretch value. The memory stretch is implemented using the Clock Control Special Function Register at
SFR location 8Eh. The stretch value is selected using bits CKCON.2-0. In the table, these bits are referred
to as M2 through M0. The first stretch (default) allows the use of common 120 ns or 150 ns RAMs
without dramatically lengthening the memory access.
DATA MEMORY CYCLE STRETCH VALUES Table 3
CKCON.2-0
MEMORY
RD
or WR STROBE
STROBE WIDTH
MD2
MD1
MD0
CYCLES
WIDTH IN CLOCKS
TIME @ 25 MHz
0
2
80 ns
0
1
3 (default)
4
160 ns
0
1
0
4
8
320 ns
0
1
5
12
480 ns
1
0
6
16
640 ns
1
0
1
7
20
800 ns
1
0
8
24
960 ns
1
9
28
1120 ns
相關(guān)PDF資料
PDF描述
DS80C320-FNG 8-BIT, 25 MHz, MICROCONTROLLER, PQFP44
DS80C320-FCG 8-BIT, 25 MHz, MICROCONTROLLER, PQFP44
DS80C320QNG 8-BIT, MROM, 25 MHz, MICROCONTROLLER, PQCC44
DS80C320-QCG 8-BIT, MROM, 25 MHz, MICROCONTROLLER, PQCC44
DS80C320-MNG 8-BIT, MROM, 25 MHz, MICROCONTROLLER, PDIP40
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
DS80C320-ECG/T&R 制造商:Maxim Integrated Products 功能描述:IC MCU HI SPEED 25MHZ 44-TQFP
DS80C320-ECG/T&R 功能描述:8位微控制器 -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
DS80C320-ECG+ 功能描述:8位微控制器 -MCU High-Speed Low-Power 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
DS80C320-ECL 功能描述:8位微控制器 -MCU High-Speed Low-Power 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
DS80C320-ECL/T&R 制造商:Maxim Integrated Products 功能描述:IC MCU HI SPEED 33MHZ 44-TQFP