收藏本站
...the world's most energy friendly microcontrollers
low for one bit-period. This signals the start of a frame, and is used for synchronization. Following the
start bit are 8 or 9 data bits and an optional parity bit. The data is transmitted with the least significant
bit first. Finally, a number of stop-bits, where the line is driven high, end the frame. The frame format
is shown in Figure 18.2 (p. 221) .
Figure 18.2. LEUART Asynchronous Frame Format
Fram e
Stop or idle
Start o r idle
S
0
1
2
3
4
5
6
7
[ 8]
[ P]
Stop
The number of data bits in a frame is set by DATABITS in LEUARTn_CTRL, and the number of stop-bits
is set by STOPBITS in LEUARTn_CTRL. Whether or not a parity bit should be included, and whether
it should be even or odd is defined by PARITY in LEUARTn_CTRL. For communication to be possible,
all parties of an asynchronous transfer must agree on the frame format being used.
The frame format used by the LEUART can be inverted by setting INV in LEUARTn_CTRL. This affects
the entire frame, resulting in a low idle state, a high start-bit, inverted data and parity bits, and low stop-
bits. INV should only be changed while the receiver is disabled.
18.3.1.1 Parity Bit Calculation and Handling
Hardware automatically inserts parity bits into outgoing frames and checks the parity bits of incoming
frames. The possible parity modes are defined in Table 18.1 (p. 221) . When even parity is chosen,
a parity bit is inserted to make the number of high bits (data + parity) even. If odd parity is chosen, the
parity bit makes the total number of high bits odd. When parity bits are disabled, which is the default
configuration, the parity bit is omitted.
Table 18.1. LEUART Parity Bit
00
01
10
11
PARITY [1:0]
No parity (default)
Reserved
Even parity
Odd parity
Description
See Section 18.3.5.4 (p. 226) for more information on parity bit handling.
18.3.2 Clock Source
The LEUART clock source is selected by the LFB bit field the CMU_LFCLKSEL register. The clock is
prescaled by the LEUARTn bitfield in the CMU_LFBPRESC0 register and enabled by the LEUARTn bit
in the CMU_LFBCLKEN0.
To use this module, the LE interface clock must be enabled in CMU_HFCORECLKEN0, in addition to
the module clock.
18.3.3 Clock Generation
The LEUART clock defines the transmission and reception data rate. The clock generator employs a
fractional clock divider to allow baud rates that are not attainable by integral division of the 32.768 kHz
clock that drives the LEUART.
2011-04-12 - d0001_Rev1.10
221
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