- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄379935 > COP8SCR9HLQ8 (NATIONAL SEMICONDUCTOR CORP) 8-Bit CMOS Flash Based Microcontroller with 32k Memory, Virtual EEPROM and Brownout PDF資料下載
參數(shù)資料
| 型號(hào)： | COP8SCR9HLQ8 |
| 廠商： | NATIONAL SEMICONDUCTOR CORP |
| 元件分類： | 微控制器/微處理器 |
| 英文描述： | 8-Bit CMOS Flash Based Microcontroller with 32k Memory, Virtual EEPROM and Brownout |
| 中文描述： | 8-BIT, FLASH, 20 MHz, MICROCONTROLLER, QCC44 |
| 封裝： | LLP-44 |
| 文件頁(yè)數(shù)： | 49/80頁(yè) |
| 文件大小： | 972K |
| 代理商： | COP8SCR9HLQ8 |
第1頁(yè)第2頁(yè)第3頁(yè)第4頁(yè)第5頁(yè)第6頁(yè)第7頁(yè)第8頁(yè)第9頁(yè)第10頁(yè)第11頁(yè)第12頁(yè)第13頁(yè)第14頁(yè)第15頁(yè)第16頁(yè)第17頁(yè)第18頁(yè)第19頁(yè)第20頁(yè)第21頁(yè)第22頁(yè)第23頁(yè)第24頁(yè)第25頁(yè)第26頁(yè)第27頁(yè)第28頁(yè)第29頁(yè)第30頁(yè)第31頁(yè)第32頁(yè)第33頁(yè)第34頁(yè)第35頁(yè)第36頁(yè)第37頁(yè)第38頁(yè)第39頁(yè)第40頁(yè)第41頁(yè)第42頁(yè)第43頁(yè)第44頁(yè)第45頁(yè)第46頁(yè)第47頁(yè)第48頁(yè)當(dāng)前第49頁(yè)第50頁(yè)第51頁(yè)第52頁(yè)第53頁(yè)第54頁(yè)第55頁(yè)第56頁(yè)第57頁(yè)第58頁(yè)第59頁(yè)第60頁(yè)第61頁(yè)第62頁(yè)第63頁(yè)第64頁(yè)第65頁(yè)第66頁(yè)第67頁(yè)第68頁(yè)第69頁(yè)第70頁(yè)第71頁(yè)第72頁(yè)第73頁(yè)第74頁(yè)第75頁(yè)第76頁(yè)第77頁(yè)第78頁(yè)第79頁(yè)第80頁(yè)
14.0 USART
(Continued)
many ways to calculate the two divisor factors, but one
particularly effective method would be to achieve a 1.8432
MHz frequency coming out of the first stage. The 1.8432
MHz prescaler output is then used to drive the software
programmable baud rate counter to create a 16x clock for
the following baud rates: 110, 134.5, 150, 300, 600, 1200,
1800, 2400, 3600, 4800, 7200, 9600, 19200 and 38400
(
Table 17
). Other baud rates may be created by using ap-
propriate divisors. The 16x clock is then divided by 16 to
provide the rate for the serial shift registers of the transmitter
and receiver.
TABLE 17. Baud Rate Divisors
(1.8432 MHz Prescaler Output)
Baud Rate
Baud Rate
Divisor 1 (N-1)
1046
855
767
383
191
95
63
47
31
23
15
11
5
2
110 (110.03)
134.5 (134.58)
150
300
600
1200
1800
2400
3600
4800
7200
9600
19200
38400
Note:
The entries in
Table 17
assume a prescaler output of 1.8432 MHz. In
asynchronous mode the baud rate could be as high as 1250k.
TABLE 18. Prescaler Factors
Prescaler
Select
00000
00001
00010
00011
00100
00101
00110
00111
Prescaler
Factor
NO CLOCK
1
1.5
2
2.5
3
3.5
4
Prescaler
Select
01000
01001
01010
01011
01100
01101
01110
01111
10000
10001
10010
10011
10100
10101
10110
10111
11000
11001
11010
11011
11100
11101
11110
11111
Prescaler
Factor
4.5
5
5.5
6
6.5
7
7.5
8
8.5
9
9.5
10
10.5
11
11.5
12
12.5
13
13.5
14
14.5
15
15.5
16
As an example, consideringAsynchronous Mode and a crys-
tal frequency of 4.608 MHz, the prescaler factor selected is:
(4.608 x 2)/1.8432 = 5
The 5 entry is available in
Table 18
. The 1.8432 MHz pres-
caler output is then used with proper Baud Rate Divisor
(
Table 17
) to obtain different baud rates. For a baud rate of
19200 e.g., the entry in
Table 17
is 5.
N 1 = 5 (N 1 is the value from
Table 17
)
N = 6 (N is the Baud Rate Divisor)
Baud Rate = 1.8432 MHz/(16 x 6) = 19200
The divide by 16 is performed because in the asynchronous
mode, the input frequency to the USART is 16 times the
baud rate. The equation to calculate baud rates is given
below.
The actual Baud Rate may be found from:
BR = (F
C
x 2)/(16 x N x P)
Where:
BR is the Baud Rate
F
C
is the crystal frequency
N is the Baud Rate Divisor (
Table 17
)
P is the Prescaler Divide Factor selected by the value in the
Prescaler Select Register (
Table 18
)
Note:
In the Synchronous Mode, the divisor 16 is replaced
by two.
Example:
Asynchronous Mode:
Crystal Frequency = 5 MHz
Desired baud rate = 19200
10138927
FIGURE 24. USART BAUD Clock Generation
C
www.national.com
49
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| COP8SDR9HLQ8 | 8-Bit CMOS Flash Based Microcontroller with 32k Memory, Virtual EEPROM and Brownout |
| COP8SCR9HVA7 | 8-Bit CMOS Flash Based Microcontroller with 32k Memory, Virtual EEPROM and Brownout |
| COP8SDR9HVA7 | 8-Bit CMOS Flash Based Microcontroller with 32k Memory, Virtual EEPROM and Brownout |
| COP8SBR9HVA8 | 8-Bit CMOS Flash Based Microcontroller with 32k Memory, Virtual EEPROM and Brownout |
| COP8SCR9HVA8 | 8-Bit CMOS Flash Based Microcontroller with 32k Memory, Virtual EEPROM and Brownout |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| COP8SCR9HVA7 | 制造商:NSC 制造商全稱:National Semiconductor 功能描述:8-Bit CMOS Flash Based Microcontroller with 32k Memory, Virtual EEPROM and Brownout |
| COP8SCR9HVA8 | 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 |
| COP8SCR9HVA8 NOPB | 制造商:National Semiconductor 功能描述:MCU 8-bit COP8 CISC 32KB Flash 3.3V/5V 44-Pin PLCC Rail |
| COP8SCR9HVA8/63SN | 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 |
| COP8SCR9HVA8/NOPB | 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 |
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。