This application note demonstrates how to write an Inter Integrated Circuit bus driver (I2C) for the XA-S3 16-bitMicrocontroller from Philips Semiconductors.Not only the driver software is given. This note also contains a set of (example) interface routines and a smalldemo application program. All together it offers the user a quick start in writing a complete I2C system applicationwith the PXAS3x.The driver routines support interrupt driven single master transfers. Furthermore, the routines are suitable foruse in conjunction with real time operating systems.
上传时间: 2013-11-02
上传用户:zw380105939
The 87C576 includes two separate methods of programming theEPROM array, the traditional modified Quick-Pulse method, and anew On-Board Programming technique (OBP).Quick Pulse programming is a method using a number of devicepins in parallel (see Figure 1) and is the traditional way in which87C51 family members have been programmed. The Quick-Pulsemethod supports the following programming functions:– program USER EPROM– verify USER EPROM– program KEY EPROM– program security bits– verify security bits– read signature bytesThe Quick-Pulse method is quite easily suited to standardprogramming equipment as evidenced by the numerous vendors of87C51 compatible programmers on the market today. Onedisadvantage is that this method is not well suited to programming inthe embedded application because of the large number of signallines that must be isolated from the application. In addition, parallelsignals from a programmer would need to be cabled to theapplication’s circuit board, or the application circuit board wouldneed to have logic built-in to perform the programming functions.These requirements have generally made in-circuit programmingusing the modified Quick Pulse method impractical in almost all87C51 family applications.
上传时间: 2013-10-21
上传用户:xiaozhiqban
当拿到一张CASE单时,首先得确定的是能用什么母体才能实现此功能,然后才能展开对外围硬件电路的设计,因此首先得了解每个母体的基本功能及特点,下面大至的介绍一下本公司常用的IC:单芯片解决方案• SN8P1900 系列– 高精度 16-Bit 模数转换器– 可编程运算放大器 (PGIA)• 信号放大低漂移: 2V• 放大倍数可编程: 1/16/64/128 倍– 升压- 稳压调节器 (Charge-Pump Regulator)• 电源输入: 2.4V ~ 5V• 稳压输出: e.g. 3.8V at SN8P1909– 内置液晶驱动电路 (LCD Driver)– 单芯片解决方案 • 耳温枪 SN8P1909 LQFP 80 Pins• 5000 解析度量测器 SN8P1908 LQFP 64 Pins• 体重计 SN8P1907 SSOP 48 Pins单芯片解决方案• SN8P1820 系列– 精确的12-Bit 模数转换器– 可编程运算放大器 (PGIA)• Gain Stage One: Low Offset 5V, Gain: 16/32/64/128• Gain Stage One: Low Offset 2mV, Gain: 1.3 ~ 2.5– 升压- 稳压调节器• 电源输入: 2.4V ~ 5V• 稳压输出: e.g. 3.8V at SN8P1829– 内置可编程运算放大电路– 内置液晶驱动电路 – 单芯片解决方案 • 电子医疗器 SN8P1829 LQFP 80 Pins 高速/低功耗/高可靠性微控制器• 最新SN8P2000 系列– SN8P2500/2600/2700 系列– 高度抗交流杂讯能力• 标准瞬间电压脉冲群测试 (EFT): IEC 1000-4-4• 杂讯直接灌入芯片电源输入端• 只需添加1颗 2.2F/50V 旁路电容• 测试指标稳超 4000V (欧规)– 高可靠性复位电路保证系统正常运行• 支持外部复位和内部上电复位• 内置1.8V 低电压侦测可靠复位电路• 内置看门狗计时器保证程序跳飞可靠复位– 高抗静电/栓锁效应能力– 芯片工作温度有所提高: -200C ~ 700C 工规芯片温度: -400C ~ 850C 高速/低功耗/高可靠性微控制器• 最新 SN8P2000 系列– SN8P2500/2600/2700 系列– 1T 精简指令级结构• 1T: 一个外部振荡周期执行一条指令• 工作速度可达16 MIPS / 16 MHz Crystal– 工作消耗电流 < 2mA at 1-MIPS/5V– 睡眠模式下消耗电流 < 1A / 5V额外功能• 高速脉宽调制输出 (PWM)– 8-Bit PWM up to 23 KHz at 12 MHz System Clock– 6-Bit PWM up to 93 KHz at 12 MHz System Clock– 4-Bit PWM up to 375 KHz at 12 MHz System Clock• 内置高速16 MHz RC振荡器 (SN8P2501A)• 电压变化唤醒功能• 可编程控制沿触发/中断功能– 上升沿 / 下降沿 / 双沿触发• 串行编程接口
上传时间: 2013-10-21
上传用户:jiahao131
Abstract: Designers who must interface 1-Wire temperature sensors with Xilinx field-programmable gate arrays(FPGAs) can use this reference design to drive a DS28EA00 1-Wire slave device. The downloadable softwarementioned in this document can also be used as a starting point to connect other 1-Wire slave devices. The systemimplements a 1-Wire master connected to a UART and outputs temperature to a PC from the DS28EA00 temperaturesensor. In addition, high/low alarm outputs are displayed from the DS28EA00 PIO pins using LEDs.
标签: PicoBlaze Create Master Xilinx
上传时间: 2013-11-05
上传用户:a6697238
a8259 可编程中断控制 altera提供 The a8259 is designed to simplify the implementation of the interrupt interface in 8088 and 8086 based microcomputer systems. The device is known as a programmable interrupt controller. The a8259 receives and prioritizes up to 8 interrupts, and in the cascade mode, this can be expanded up to 64 interrupts. An asynchronous reset and a clock input have been added to improve operation and reliability.
上传时间: 2014-11-29
上传用户:zhyiroy
多远程二极管温度传感器-Design Considerations for pc thermal management Multiple RDTS (remote diode temperature sensing) provides the most accurate method of sensing an IC’s junction temperature. It overcomes thermal gradient and placement issues encountered when trying to place external sensors. PCB component count decreases when using a device that provides multiple inputs.Better temperature sensing improves product performance and reliability. Disk drive data integrity suffers at elevated temperatures. IBM published an article stating that a 5°C rise in operating temperature causes a 15% increase in the drive’s failure rate. The overall performance of a system can be improved by providing a more accurate temperature measurement of the most critical devices allowing them to run just a few degrees hotter.The LM83 directly senses its own temperature and the temperature of three external PN junctions. One is dedicated to the CPU of choice, the other two go to other parts of your system that need thermal monitoring such as the disk drive or graphics chip. The SMBus-compatible LM83 supports SMBus timeout and logic levels. The LM83 has two interrupt outputs; one for user-programmable limits and WATCHDOG capability (INT), the other is a Critical Temperature Alarm output (T_CRIT_A) for system power supply shutdown.
标签: Considerat Design 远程 二极管
上传时间: 2014-12-21
上传用户:ljd123456
The C8051F020/1/2/3 devices are fully integrated mixed-signal System-on-a-Chip MCUs with 64 digital I/O pins (C8051F020/2) or 32 digital I/O pins (C8051F021/3). Highlighted features are listed below; refer to Table 1.1 for specific product feature selection.
上传时间: 2013-11-08
上传用户:lwq11
针对UHF读写器设计中,在符合EPC Gen2标准的情况下,对标签返回的高速数据进行正确解码以达到正确读取标签的要求,提出了一种新的在ARM平台下采用边沿捕获统计定时器数判断数据的方法,并对FM0编码进行解码。与传统的使用定时器定时采样高低电平的FM0解码方法相比,该解码方法可以减少定时器定时误差累积的影响;可以将捕获定时器数中断与数据判断解码相对分隔开,使得中断对解码影响很小,实现捕获与解码的同步。通过实验表明,这种方法提高了解码的效率,在160 Kb/s的接收速度下,读取一张标签的时间约为30次/s。 Abstract: Aiming at the requirement of receiving correctly decoded data from the tag under high-speed communication which complied with EPC Gen2 standard in the design of UHF interrogator, the article introduced a new technology for FM0 decoding which counted the timer counter to judge data by using the edge interval of signal capture based on the ARM7 platform. Compared with the traditional FM0 decoding method which used the timer timed to sample the high and low level, the method could reduce the accumulation of timing error and could relatively separate capture timer interrupt and the data judgment for decoding, so that the disruption effect on the decoding was small and realizd synchronization of capture and decoding. Testing result shows that the method improves the efficiency of decoding, at 160 Kb/s receiving speed, the time of the interrogator to read a tag is about 30 times/s.
上传时间: 2013-11-10
上传用户:liufei
This example shows how to update at regulate period the WWDG counter using theEarly Wakeup interrupt (EWI). The WWDG timeout is set to 262ms, refresh window set to 41h and the EWI isenabled. When the WWDG counter reaches 40h the EWI is generated and in the WWDGISR the counter is refreshed to prevent a WWDG reset and led connected to PC.07is toggled.The EXTI line9 is connected to PB.09 pin and configured to generate an interrupton falling edge.In the NVIC, EXTI line9 to 5 interrupt vector is enabled with priority equal to 0and the WWDG interrupt vector is enabled with priority equal to 1 (EXTI IT > WWDG IT). The EXTI Line9 will be used to simulate a software failure: once the EXTI line9event occurs (by pressing Key push-button on EVAL board) the correspondent interruptis served, in the ISR the led connected to PC.07 is turned off and the EXTI line9pending bit is not cleared. So the CPU will execute indefinitely EXTI line9 ISR andthe WWDG ISR will never be entered(WWDG counter not updated). As result, when theWWDG counter falls to 3Fh the WWDG reset occurs.If the EXTI line9 event don抰 occurs the WWDG counter is indefinitely refreshed inthe WWDG ISR which prevent from WWDG reset. If the WWDG reset is generated, after resuming from reset a led connected to PC.06is turned on. In this example the system is clocked by the HSE(8MHz).
上传时间: 2013-11-11
上传用户:gundamwzc
#include <reg51.h>#include <main.h>#include <interrupt.h> cs5460a应用电路(含源程序)bit code table_odd_even_bit[16]={0,1,1,0,1,0,0,1,1,0,0,1,0,1,1,0}; extern uchar rs485_timeout,pointer_buf485;extern uchar rs485_buf[MAX_485_LEN];extern uchar idata spi_buf[MAX_SPI_LEN];extern uchar pointer_send,send_len; extern uchar count_1s;//extern uint count_2min;extern uint count_10s;extern uchar oper_len,send_offset,chk_sum,send_i;extern bit flag_send_data,flag_level,flag_drdy,flag_data_ok;
上传时间: 2014-01-24
上传用户:heart_2007