收藏本站
...the world's most energy friendly microcontrollers
Figure 16.5 (p. 186) . With OVS=0 in USARTn_CTRL, the start and data bits are thus sampled at
locations 8, 9 and 10 in the figure, locations 4, 5 and 6 for OVS=1 and locations 3, 4, and 5 for OVS=2.
The value of a sampled bit is determined by majority vote. If two or more of the three bit-samples are
high, the resulting bit value is high. If the majority is low, the resulting bit value is low.
Majority vote is used for all oversampling modes except 4x oversampling. In this mode, a single sample
is taken at position 3 as shown in Figure 16.5 (p. 186) .
If the value of the start bit is found to be high, the reception of the frame is aborted, filtering out false
start bits possibly generated by noise on the input.
Figure 16.5. USART Sampling of Start and Data Bits
Idle
Start bit
Bit 0
0
0
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 1
2
3
4
5
6
7
8
9 10 11 12 13
0
1
2
3
4
5
6
7
8
1
2
3
4
5
6
7
0
1
2
3
4
5
6
1
2
3
4
5
1
2
3
4
1
2
3
4
If the baud rate of the transmitter and receiver differ, the location each bit is sampled will be shifted
towards the previous or next bit in the frame. This is acceptable for small errors in the baud rate, but for
larger errors, it will result in transmission errors.
When the number of stop bits is 1 or more, stop bits are sampled like the start and data bits as seen in
Figure 16.6 (p. 186) . When a stop bit has been detected by sampling at positions 8, 9 and 10 for normal
mode, or 4, 5 and 6 for smart mode, the USART is ready for a new start bit. As seen in Figure 16.6 (p.
186) , a stop-bit of length 1 normally ends at c, but the next frame will be received correctly as long as
the start-bit comes after position a for OVS=0 and OVS=3, and b for OVS=1 and OVS=2.
Figure 16.6. USART Sampling of Stop Bits when Number of Stop Bits are 1 or More
a
b
c
n ’th bit
1 stop bit
Idle or start bit
13 14 15 16 1
2
3
4
5
6
7
8
9 10 0/1 X
X
X
X
X
7
6
8
1
1
2
2
3
3
4
5
4
6
5
0/1
X
0/1
1
4
1
2
3
0/1
1
2011-04-12 - d0001_Rev1.10
186
www.energymicro.com
发布紧急采购，3分钟左右您将得到回复。

采购需求

(若只采购一条型号，填写一行即可)

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

发布成功！您可以继续发布采购。也可以进入我的后台，查看报价

*型号 *数量 厂商 批号 封装
添加更多采购

我的联系方式

*
*
*
相关PDF资料
EFM32GG-STK3700 KIT STARTER GIANT GECKO
EFM32LG-DK3650 KIT DEV EFM32 LEOPARD GECKO
EK-K7-KC705-CES-G-J KINTEX-7 FPGA KC705 EVAL KIT
EK-S6-SP601-G KIT EVAL SPARTAN 6 SP601
EK-S6-SP605-G KIT EVAL SPARTAN 6 SP605
EK-V6-ML631-G-J VIRTEX-6 HXT FPGA ML631 EVAL KIT
EK-V7-VC707-CES-G VIRTEX-7 VC707 EVAL KIT
EK-Z7-ZC702-CES-G ZYNQ-7000 EPP ZC702 EVAL KIT
相关代理商/技术参数
EFM32GG230F1024 功能描述:ARM微控制器 - MCU 1024KB FL 128KB RAM RoHS:否 制造商:STMicroelectronics 核心:ARM Cortex M4F 处理器系列:STM32F373xx 数据总线宽度:32 bit 最大时钟频率:72 MHz 程序存储器大小:256 KB 数据 RAM 大小:32 KB 片上 ADC:Yes 工作电源电压:1.65 V to 3.6 V, 2 V to 3.6 V, 2.2 V to 3.6 V 工作温度范围:- 40 C to + 85 C 封装 / 箱体:LQFP-48 安装风格:SMD/SMT
EFM32GG230F1024G-E-QFN64R 功能描述:IC MCU 32BIT 1MB FLASH 64QFN 制造商:silicon labs 系列:Giant Gecko 包装:剪切带（CT） 零件状态:在售 核心处理器:ARM? Cortex?-M3 核心尺寸:32-位 速度:48MHz 连接性:I2C，IrDA，智能卡，SPI，UART/USART 外设:欠压检测/复位，DMA，POR，PWM，WDT I/O 数:56 程序存储容量:1MB（1M x 8） 程序存储器类型:闪存 EEPROM 容量:- RAM 容量:128K x 8 电压 - 电源（Vcc/Vdd）:1.98 V ~ 3.8 V 数据转换器:A/D 8x12b，D/A 2x12b 振荡器类型:内部 工作温度:-40°C ~ 85°C（TA） 封装/外壳:64-VFQFN 裸露焊盘 供应商器件封装:64-QFN（9x9） 标准包装:1
EFM32GG230F1024-QFN64 制造商:Energy Micro AS 功能描述:GIANT GECKO MCU - Cut TR (SOS) 制造商:Energy Micro 功能描述:GIANT GECKO MCU 制造商:Energy Micro AS 功能描述:IC MCU 32BIT 1MB FLASH 64QFN
EFM32GG230F1024-QFN64T 制造商:Energy Micro AS 功能描述:GIANT GECKO MCU - Trays
EFM32GG230F1024-QFN64-T 制造商:Energy Micro AS 功能描述:IC MCU 32BIT 1MB FLASH 64QFN
EFM32-GG230F1024-SK 制造商:Energy Micro AS 功能描述:GIANT GECKO SAMPLE KIT - Bulk
EFM32GG230F1024-T 制造商:Energy Micro AS 功能描述:IC MCU 32BIT 1MB FLASH 64QFN
EFM32GG230F512 功能描述:ARM微控制器 - MCU 512KB FL 128KB RAM RoHS:否 制造商:STMicroelectronics 核心:ARM Cortex M4F 处理器系列:STM32F373xx 数据总线宽度:32 bit 最大时钟频率:72 MHz 程序存储器大小:256 KB 数据 RAM 大小:32 KB 片上 ADC:Yes 工作电源电压:1.65 V to 3.6 V, 2 V to 3.6 V, 2.2 V to 3.6 V 工作温度范围:- 40 C to + 85 C 封装 / 箱体:LQFP-48 安装风格:SMD/SMT