基于MSP430的心电监测系统
摘要
心电图是临床诊断心脏病的重要依据。目前,临床上的心电检测仪器虽然可以72小时记录心电信号,但有其自身缺陷。例如不能实时观测信号,不方便病人携带等。
本课题研究的心电信号检测系统,以新型的低功耗单片机MSP430F413为核心,通过无线发射芯片NRF2401把采集的心电信号发射出去,并由接受端接受信号,把心电信号传输给PC机以供进一步分析和处理。该仪器的心电测量部分,采用A/D转换芯片TLC549。该芯片和MSP430连接时利用三个数字I/O接口,驱动TLC549 A/D转换采用异步串行接口,成本低廉,有利于降低整个系统的成本。无线发射与接收部分的设计用了NRF2401芯片。该芯片传输距离远,外围设备简单,操作方便。串行通信部分,采用利用Timer_A用软件模拟串行通信的方法。这种方法的传输可靠性较高,对系统资源的占用较少。由于没有采用硬件UART模块,也大幅降低了系统的成本。
该仪器可以准确的测得患者的心电,和PC相连还可以实时远距离的监测患者的心电。通过进一步编写计算机软件还可以记录心电的变化,绘制心电图。
The ECG has been wildly used in diagnosing heart disease . At present , the ECG monitoring system have disadvantages . For example , it can not emit the signal real time and is not convenience . With the development of electron technology , wireless communication technology and computer technology , the ECG monitoring system is going to be smaller and more convenient.
The ECG monitoring system which is designed in this paper based on the MSP430 Single Chip Micyoco . Using the wireless communication chip , nRF2401 , the emitting part send signals to the incepting part which translating the signals to the PC . The PC will analyzing and deal with the information.
The main part of this system is new type、low power MCU MSP430 manufactured by TI company. This MCU is very suitable for ultra-low consumption situation, and it can work long time powered by battery. This MSP430F413 has low price, a good many function can achieved via software, use less hardware. So the cost of this system is cheap and it is in favor of extend application.
MSP430 can debug online through JTAG., we only need a PC and a simulator during exploitation. We can use IAR Embedded Workbench for MSP430 and C-SPY as exploitation software. This feature can save time and money in exploitation.
This system catch the ECG in the body ; the analogue ECG is transformed into digital ECG by amplifying circuit , filtering circuit and A/D converting circuit . The emitting and incepting part base on the chip nRF2401 . The function of the communicating with PC is to transmit the temperature to PC.
This part use Timer_A to realize soft UART . In the way , the signal can be transmit safely . The cost of this system is low what with there is no hard UART .
This system is made of three parts . The fist one can catch the ECG and translate it . We can get the normative I , II , III electrocardiogram by embedding electrode in the body .There is a selector to select the real-time signal which is going to send to amplifying circuit . The selector which is used in the paper is CD4052 . The ECG which is caught in the body is feebleness . We need to amply the signal . The amplifying circuit which is used in the paper is differential amplifying circuit . Analog filter is used to reduce the disturbing influence . The ECG is translated to digital signals by A/D circuit .TCL549 can accomplish the work in 17μs.
The second part is the wireless communication . The main function of this part is transmitting ECG at long bowls . To carry out the function the nRF2401 is designed . The nRF2401 is wireless emitting and incepting chip .
It worked in 2.4～2.5GHz ISM . There are a Frequency Synthesis a , a power amplifier , a oscillators and a modulator . The Ramp-rat and the communications channel can be enactment by software . It is energy-saving .
When it is sending signal in -5bBm , the working current is only 10.5mA . When it is incepting signal , the working current is 18mA . It has several working mode which are low-power and is energy-saving and convenient . The nRF2401 can incept two channel with one antenna basing on a new technology ' DuoCeiverTM ' .
The third part of the system is UART. The function of the part is to transmit the temperature to PC. This part use Timer_A to realize soft UART. The communication protocol is 1stop+8data+1start. The Baud-rate is 1200bit/s. This Baud-rate generates by Timer_A interrupt. We work out the time between each bit and make Timer_A to interrupt by the time. Data can be transmitted by interrupt program. RS232 protocol which applied by PC serial port is different from TTL which applied by MCU. We use SP3220E to transform TTL to RS232. SP3220E can operate from a 3.0V to 5.5V power supply, and it only needs 5 additional capacitances.
UART program on PC is compiled by Visual Basic. We use MSComm to realize the function.
This system can catch ECG accurately and can monitor ECG real time . It can memorize the movement of the patient by compiling software.
本课题研究的心电信号检测系统,以新型的低功耗单片机MSP430F413为核心,通过无线发射芯片NRF2401把采集的心电信号发射出去,并由接受端接受信号,把心电信号传输给PC机以供进一步分析和处理。该仪器的心电测量部分,采用A/D转换芯片TLC549。该芯片和MSP430连接时利用三个数字I/O接口,驱动TLC549 A/D转换采用异步串行接口,成本低廉,有利于降低整个系统的成本。无线发射与接收部分的设计用了NRF2401芯片。该芯片传输距离远,外围设备简单,操作方便。串行通信部分,采用利用Timer_A用软件模拟串行通信的方法。这种方法的传输可靠性较高,对系统资源的占用较少。由于没有采用硬件UART模块,也大幅降低了系统的成本。
该仪器可以准确的测得患者的心电,和PC相连还可以实时远距离的监测患者的心电。通过进一步编写计算机软件还可以记录心电的变化,绘制心电图。
The ECG has been wildly used in diagnosing heart disease . At present , the ECG monitoring system have disadvantages . For example , it can not emit the signal real time and is not convenience . With the development of electron technology , wireless communication technology and computer technology , the ECG monitoring system is going to be smaller and more convenient.
The ECG monitoring system which is designed in this paper based on the MSP430 Single Chip Micyoco . Using the wireless communication chip , nRF2401 , the emitting part send signals to the incepting part which translating the signals to the PC . The PC will analyzing and deal with the information.
The main part of this system is new type、low power MCU MSP430 manufactured by TI company. This MCU is very suitable for ultra-low consumption situation, and it can work long time powered by battery. This MSP430F413 has low price, a good many function can achieved via software, use less hardware. So the cost of this system is cheap and it is in favor of extend application.
MSP430 can debug online through JTAG., we only need a PC and a simulator during exploitation. We can use IAR Embedded Workbench for MSP430 and C-SPY as exploitation software. This feature can save time and money in exploitation.
This system catch the ECG in the body ; the analogue ECG is transformed into digital ECG by amplifying circuit , filtering circuit and A/D converting circuit . The emitting and incepting part base on the chip nRF2401 . The function of the communicating with PC is to transmit the temperature to PC.
This part use Timer_A to realize soft UART . In the way , the signal can be transmit safely . The cost of this system is low what with there is no hard UART .
This system is made of three parts . The fist one can catch the ECG and translate it . We can get the normative I , II , III electrocardiogram by embedding electrode in the body .There is a selector to select the real-time signal which is going to send to amplifying circuit . The selector which is used in the paper is CD4052 . The ECG which is caught in the body is feebleness . We need to amply the signal . The amplifying circuit which is used in the paper is differential amplifying circuit . Analog filter is used to reduce the disturbing influence . The ECG is translated to digital signals by A/D circuit .TCL549 can accomplish the work in 17μs.
The second part is the wireless communication . The main function of this part is transmitting ECG at long bowls . To carry out the function the nRF2401 is designed . The nRF2401 is wireless emitting and incepting chip .
It worked in 2.4～2.5GHz ISM . There are a Frequency Synthesis a , a power amplifier , a oscillators and a modulator . The Ramp-rat and the communications channel can be enactment by software . It is energy-saving .
When it is sending signal in -5bBm , the working current is only 10.5mA . When it is incepting signal , the working current is 18mA . It has several working mode which are low-power and is energy-saving and convenient . The nRF2401 can incept two channel with one antenna basing on a new technology ' DuoCeiverTM ' .
The third part of the system is UART. The function of the part is to transmit the temperature to PC. This part use Timer_A to realize soft UART. The communication protocol is 1stop+8data+1start. The Baud-rate is 1200bit/s. This Baud-rate generates by Timer_A interrupt. We work out the time between each bit and make Timer_A to interrupt by the time. Data can be transmitted by interrupt program. RS232 protocol which applied by PC serial port is different from TTL which applied by MCU. We use SP3220E to transform TTL to RS232. SP3220E can operate from a 3.0V to 5.5V power supply, and it only needs 5 additional capacitances.
UART program on PC is compiled by Visual Basic. We use MSComm to realize the function.
This system can catch ECG accurately and can monitor ECG real time . It can memorize the movement of the patient by compiling software.
引文
【1】姚泰主编. 生理学. 人民卫生出版社. 2003 年,第 6 版:205-206
【2】MSP430-FET 使用指南. 利尔达单片机技术有限公司
【3】胡大可. MSP430 系列 FLASH 型超低功耗 16 位单片机. 北京航空航天大学出版社. 2001 年 11 月第 1 版
【4】MSP430x41x MIXED SIGNAL MICROCONTROLLER, Texas Instruments, Literature Number SLAS340G, MAY 2001
【5】谭浩强. C 程序设计. 清华大学出版社. 1999 年 12 月第 2 版:3
【6】张晞,王德银,张晨. MSP430 系列单片机实用 C 语言程序设计. 人们邮电出版社. 2005 年 9 月第 1 版
【7】魏小龙. MSP430 串行异步通讯原理与实现. 电子世界. 2005 年 3 期:20-21
【8】李朝青. PC机及单片机数据通信技术. 北京航空航天大学出版社. 2002
【9】王玉彩,王福增,王渝,李志华. MSP430F1101单片机在数据采集中的应用. 现代电子技术. 2005年第21期:70~71
【10】丁鹏飞.徐国军. MSP430 中 Timer_A and Timer_B 的 UART 运用. 电子质量. 2003 年第 5 期:106~107
【11】彭承琳. 生物医学传感器原理及应用. 高等教育出版社. 2000 年第 1 版:201~207
【12】许华杰.明健. 用 MSP430 实现斜率 A/D 转换. 电子产品世界. 2001,7:26~27
【13】魏小龙. MSP430 定时器的使用. 电子世界. 2004 年 11 期:28~29
【14】SP3220E True +3.0 to +5.0V RS-232 Transceivers. Sipex Corporation.2002,7
【15】胡汉才. 单片机原理及其接口技术. 清华大学出版社
【16】魏源源. Visual Basic 5.0 中文版程序设计教程. 电子工业出版社. 1998年第1版
【17】俸远祯,阎慧娟.计算机组成原理. 电子工业出版社
【18】秦龙.MSP430单片机C语言应用程序设计室例精讲.电子工业出版社
【19】陈卫卫. C/C++程序设计教程 中国科技出版社
【20】nRF2401技术手册 2.4GHz射频收发芯片nRF2401及其应用
【21】季燕飞.段焕春 基于单片机内置比较器的高精度 A/D 微控设计网
【22】CD4052技术手册 模拟开关介绍及应用电路
【23】康华光.陈大钦 电子技术基础 高等教育出版社
【24】贾民谊.诊断学. 人民卫生出版社. 2000年第3版: 5-7
【25】李朝青. PC机及单片机数据通信技术. 北京航空航天大学出版社. 2002
【26】李卫.陶维青. 基于 MSP430 的串行通信软件设计. 仪器仪表用户. 2004,1:79~80
【27】Mark E. Buccini . Implementing a UART Function With the 8-Bit Interval Timer/Counter. Texas Instruments. 1999
【28】刘克哲. 物理学. 高等教育出版社. 1999年9月第2版:253
【29】余学飞. 医学电子仪器原理与设计. 华南理工大学出版社. 2000
【30】牛洪涛. RS - 232电平与TTL电平之间的转换. 电子·仪器仪表用户. 1998 年 第1期:33-34
【31】布鲁克斯.(译)刘雷波.信号完整性问题和印制电路板设计.机械工业出版社.2005年8月第1版
【32】王卫东.模拟电子电路基础.西安电子工业大学出版社.2003年2月第1版
【33】彭玉华.小波变换与工程应用.科学出版社.1999年9月
【34】(美) Theodore S. Rappaport.无线通信原理与应用(第二版)(中文版) 电子工业出版社.2006年7月第1版
【35】张肃文.高频电子线路(第4版). 高等教育出版社.2004年11月
【36】(美)王小东.无线通信系统-信号检测与处理技术(英文版). 电子工业出版社 2004年6月
【37】(日)铃木宪次.无线电收音机及无线电路的设计与制作. 科学出版社 2006年8月
【38】杨振江.孙占彪.王曙梅.布线涛.智能仪器与数据采集系统中的新器件及应用 西安电子科技大学出版社.2001年12月
【39】谢嘉奎.电子线路-非线性部分(第4版).高等教育出版社.2005年12月第4版
【40】陈邦嫒.射频通信电路(第二版).科学出版社.2006年8月
【2】MSP430-FET 使用指南. 利尔达单片机技术有限公司
【3】胡大可. MSP430 系列 FLASH 型超低功耗 16 位单片机. 北京航空航天大学出版社. 2001 年 11 月第 1 版
【4】MSP430x41x MIXED SIGNAL MICROCONTROLLER, Texas Instruments, Literature Number SLAS340G, MAY 2001
【5】谭浩强. C 程序设计. 清华大学出版社. 1999 年 12 月第 2 版:3
【6】张晞,王德银,张晨. MSP430 系列单片机实用 C 语言程序设计. 人们邮电出版社. 2005 年 9 月第 1 版
【7】魏小龙. MSP430 串行异步通讯原理与实现. 电子世界. 2005 年 3 期:20-21
【8】李朝青. PC机及单片机数据通信技术. 北京航空航天大学出版社. 2002
【9】王玉彩,王福增,王渝,李志华. MSP430F1101单片机在数据采集中的应用. 现代电子技术. 2005年第21期:70~71
【10】丁鹏飞.徐国军. MSP430 中 Timer_A and Timer_B 的 UART 运用. 电子质量. 2003 年第 5 期:106~107
【11】彭承琳. 生物医学传感器原理及应用. 高等教育出版社. 2000 年第 1 版:201~207
【12】许华杰.明健. 用 MSP430 实现斜率 A/D 转换. 电子产品世界. 2001,7:26~27
【13】魏小龙. MSP430 定时器的使用. 电子世界. 2004 年 11 期:28~29
【14】SP3220E True +3.0 to +5.0V RS-232 Transceivers. Sipex Corporation.2002,7
【15】胡汉才. 单片机原理及其接口技术. 清华大学出版社
【16】魏源源. Visual Basic 5.0 中文版程序设计教程. 电子工业出版社. 1998年第1版
【17】俸远祯,阎慧娟.计算机组成原理. 电子工业出版社
【18】秦龙.MSP430单片机C语言应用程序设计室例精讲.电子工业出版社
【19】陈卫卫. C/C++程序设计教程 中国科技出版社
【20】nRF2401技术手册 2.4GHz射频收发芯片nRF2401及其应用
【21】季燕飞.段焕春 基于单片机内置比较器的高精度 A/D 微控设计网
【22】CD4052技术手册 模拟开关介绍及应用电路
【23】康华光.陈大钦 电子技术基础 高等教育出版社
【24】贾民谊.诊断学. 人民卫生出版社. 2000年第3版: 5-7
【25】李朝青. PC机及单片机数据通信技术. 北京航空航天大学出版社. 2002
【26】李卫.陶维青. 基于 MSP430 的串行通信软件设计. 仪器仪表用户. 2004,1:79~80
【27】Mark E. Buccini . Implementing a UART Function With the 8-Bit Interval Timer/Counter. Texas Instruments. 1999
【28】刘克哲. 物理学. 高等教育出版社. 1999年9月第2版:253
【29】余学飞. 医学电子仪器原理与设计. 华南理工大学出版社. 2000
【30】牛洪涛. RS - 232电平与TTL电平之间的转换. 电子·仪器仪表用户. 1998 年 第1期:33-34
【31】布鲁克斯.(译)刘雷波.信号完整性问题和印制电路板设计.机械工业出版社.2005年8月第1版
【32】王卫东.模拟电子电路基础.西安电子工业大学出版社.2003年2月第1版
【33】彭玉华.小波变换与工程应用.科学出版社.1999年9月
【34】(美) Theodore S. Rappaport.无线通信原理与应用(第二版)(中文版) 电子工业出版社.2006年7月第1版
【35】张肃文.高频电子线路(第4版). 高等教育出版社.2004年11月
【36】(美)王小东.无线通信系统-信号检测与处理技术(英文版). 电子工业出版社 2004年6月
【37】(日)铃木宪次.无线电收音机及无线电路的设计与制作. 科学出版社 2006年8月
【38】杨振江.孙占彪.王曙梅.布线涛.智能仪器与数据采集系统中的新器件及应用 西安电子科技大学出版社.2001年12月
【39】谢嘉奎.电子线路-非线性部分(第4版).高等教育出版社.2005年12月第4版
【40】陈邦嫒.射频通信电路(第二版).科学出版社.2006年8月