参数资料
型号: COP8SGH528M8
厂商: NATIONAL SEMICONDUCTOR CORP
元件分类: 微控制器/微处理器
英文描述: LP38691/LP38693 500mA Low Dropout CMOS Linear Regulators Stable with Ceramic Output Capacitors; Package: SOT-223; No of Pins: 5
中文描述: 8-BIT, MROM, 10 MHz, MICROCONTROLLER, PDSO28
封装: PLASTIC, SOIC-28
文件页数: 31/62页
文件大小: 913K
代理商: COP8SGH528M8
8.0 USART
(Continued)
8.6 USART INTERRUPTS
The USART is capable of generating interrupts. Interrupts
are generated on Receive Buffer Full and Transmit Buffer
Empty. Both interrupts have individual interrupt vectors. Two
bytes of program memory space are reserved for each in-
terrupt vector. The two vectors are located at addresses
0xEC to 0xEF Hex in the program memory space. The
interrupts can be individually enabled or disabled using En-
able Transmit Interrupt (ETI) and Enable Receive Interrupt
(ERI) bits in the ENUI register.
The interrupt from the Transmitter is set pending, and re-
mains pending, as long as both the TBMT and ETI bits are
set. To remove this interrupt, software must either clear the
ETI bit or write to the TBUF register (thus clearing the TBMT
bit).
The interrupt from the receiver is set pending, and remains
pending, as long as both the RBFL and ERI bits are set. To
remove this interrupt, software must either clear the ERI bit
or read from the RBUF register (thus clearing the RBFL bit).
8.7 Baud Clock Generation
The clock inputs to the transmitter and receiver sections of
the USART can be individually selected to come either from
an external source at the CKX pin (port L, pin L1) or from a
source selected in the PSR and BAUD registers. Internally,
the basic baud clock is created from the oscillator frequency
through a two-stage divider chain consisting of a 1–16 (in-
crements of 0.5) prescaler and an 11-bit binary counter.
(Figure 23). The divide factors are specified through two
read/write registers shown in Figure 24 Note that the 11-bit
Baud Rate Divisor spills over into the Prescaler Select Reg-
ister (PSR). PSR is cleared upon reset.
As shown in Table 5 a Prescaler Factor of 0 corresponds to
NO CLOCK. This condition is the USART power down mode
where the USART clock is turned off for power saving pur-
pose. The user must also turn the USART clock off when a
different baud rate is chosen.
The correspondences between the 5-bit Prescaler Select
and Prescaler factors are shown in Table 5 There are many
ways to calculate the two divisor factors, but one particularly
effective method would be to achieve a 1.8432 MHz fre-
quency coming out of the first stage. The 1.8432 MHz pres-
caler 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 4). Other baud
10131740
FIGURE 22. Framing Formats
C
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相关PDF资料
PDF描述
COP8SGH528M9 LP38691/LP38693 500mA Low Dropout CMOS Linear Regulators Stable with Ceramic Output Capacitors; Package: SOT-223; No of Pins: 5
COP8SGH528N3 LP38691/LP38693 500mA Low Dropout CMOS Linear Regulators Stable with Ceramic Output Capacitors; Package: SOT-223; No of Pins: 5
COP8SGH528N6 LP38691-ADJ/LP38693-ADJ 500mA Low Dropout CMOS Linear Regulators with Adjustable Output Stable with Ceramic Output Capacitors; Package: SOT-223; No of Pins: 5
COP8SGH528N7 LP38691/LP38693 500mA Low Dropout CMOS Linear Regulators Stable with Ceramic Output Capacitors; Package: LLP; No of Pins: 6
COP8SGH528N8 LP38691/LP38693 500mA Low Dropout CMOS Linear Regulators Stable with Ceramic Output Capacitors; Package: LLP; No of Pins: 6
相关代理商/技术参数
参数描述
COP8SGR728M7 功能描述:8位微控制器 -MCU RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
COP8SGR728M7/NOPB 功能描述:8位微控制器 -MCU RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
COP8SGR728M8 功能描述:8位微控制器 -MCU RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
COP8SGR728M8/NOPB 功能描述:8位微控制器 -MCU RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT
COP8SGR728N8 功能描述:8位微控制器 -MCU RoHS:否 制造商:Silicon Labs 核心:8051 处理器系列:C8051F39x 数据总线宽度:8 bit 最大时钟频率:50 MHz 程序存储器大小:16 KB 数据 RAM 大小:1 KB 片上 ADC:Yes 工作电源电压:1.8 V to 3.6 V 工作温度范围:- 40 C to + 105 C 封装 / 箱体:QFN-20 安装风格:SMD/SMT