- 您现在的位置：买卖IC网 > PDF目录45265 > MR80C32-20/883:D (ATMEL CORP) 8-BIT, 20 MHz, MICROCONTROLLER, CQCC44 PDF资料下载
参数资料
| 型号： | MR80C32-20/883:D |
| 厂商： | ATMEL CORP |
| 元件分类： | 微控制器/微处理器 |
| 英文描述： | 8-BIT, 20 MHz, MICROCONTROLLER, CQCC44 |
| 封装： | LCC-44 |
| 文件页数： | 102/103页 |
| 文件大小： | 25028K |
第1页第2页第3页第4页第5页第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页第41页第42页第43页第44页第45页第46页第47页第48页第49页第50页第51页第52页第53页第54页第55页第56页第57页第58页第59页第60页第61页第62页第63页第64页第65页第66页第67页第68页第69页第70页第71页第72页第73页第74页第75页第76页第77页第78页第79页第80页第81页第82页第83页第84页第85页第86页第87页第88页第89页第90页第91页第92页第93页第94页第95页第96页第97页第98页第99页第100页第101页当前第102页第103页
190
8272E–AVR–04/2013
ATmega164A/PA/324A/PA/644A/PA/1284/P
Figure 19-7. Stop Bit Sampling and Next Start Bit Sampling.
The same majority voting is done to the stop bit as done for the other bits in the frame. If the stop
bit is registered to have a logic 0 value, the Frame Error (FEn) Flag will be set.
A new high to low transition indicating the start bit of a new frame can come right after the last of
the bits used for majority voting. For Normal Speed mode, the first low level sample can be at
point marked (A) in Figure 19-7 on page 190. For Double Speed mode the first low level must be
delayed to (B). (C) marks a stop bit of full length. The early start bit detection influences the
operational range of the Receiver.
19.9.3
Asynchronous Operational Range
The operational range of the Receiver is dependent on the mismatch between the received bit
rate and the internally generated baud rate. If the Transmitter is sending frames at too fast or too
slow bit rates, or the internally generated baud rate of the Receiver does not have a similar (see
Table 19-2 on page 191) base frequency, the Receiver will not be able to synchronize the
frames to the start bit.
The following equations can be used to calculate the ratio of the incoming data rate and internal
receiver baud rate.
D
Sum of character size and parity size (D = 5 to 10 bit).
S
Samples per bit. S = 16 for Normal Speed mode and S = 8 for Double Speed
mode.
S
F
First sample number used for majority voting. S
F = 8 for normal speed and SF = 4
for Double Speed mode.
S
M
Middle sample number used for majority voting. S
M = 9 for normal speed and
S
M = 5 for Double Speed mode.
R
slow
is the ratio of the slowest incoming data rate that can be accepted in relation to the
receiver baud rate. R
fast is the ratio of the fastest incoming data rate that can be
accepted in relation to the receiver baud rate.
Table 19-2 on page 191 and Table 19-3 on page 191 list the maximum receiver baud rate error
that can be tolerated. Note that Normal Speed mode has higher toleration of baud rate
variations.
12
34
56
7
8
9
10
0/1
STOP 1
123
4
5
6
0/1
RxD
Sample
(U2X = 0)
Sample
(U2X = 1)
(A)
(B)
(C)
R
slow
D
1
+
S
1
–
DS
S
F
++
-------------------------------------------
=
R
fast
D
2
+
S
D
1
+
SS
M
+
-----------------------------------
=
相关PDF资料 |
PDF描述 |
|---|---|
| MR80C32-36:RD | 8-BIT, 36 MHz, MICROCONTROLLER, CQCC44 |
| MQ80C32E-30/883:RD | 8-BIT, 30 MHz, MICROCONTROLLER, CQFP44 |
| MC80C32E-36/883 | 8-BIT, 36 MHz, MICROCONTROLLER, CDIP40 |
| MC80C52TXXX-36/883:D | 8-BIT, MROM, 36 MHz, MICROCONTROLLER, CDIP40 |
| MD80C52TXXX-30SHXXX:D | 8-BIT, MROM, 30 MHz, MICROCONTROLLER, CDIP40 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| MR80C32-25 | 制造商:未知厂家 制造商全称:未知厂家 功能描述:8-Bit Microcontroller |
| MR80C32-30 | 制造商:未知厂家 制造商全称:未知厂家 功能描述:8-Bit Microcontroller |
| MR80C32-36 | 制造商:未知厂家 制造商全称:未知厂家 功能描述:8-Bit Microcontroller |
| MR80C51BH | 制造商:ROCHESTER 制造商全称:ROCHESTER 功能描述:CMOS SINGLE - CHIP 8-BIT MICROCOMPUTER 64K program Memory Space |
| MR80C86 | 制造商:INTERSIL 制造商全称:Intersil Corporation 功能描述:CMOS 16-Bit Microprocessor |
发布紧急采购，3分钟左右您将得到回复。