cnzero/sEMG_SDK

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sEMG_SDK

SDK of sEMG functions of matlab

目的

实现思路

先对大量复用性代码进行抽象化与模块化;
对不同功能的函数代码进行分而治之；

说明文档

1. 采集程序

2. 基于窗函数的特征提取

3. 模型参数的输入与输出

README of directories/folders

acquisition

functions of acquiring sEMG/ACC online/offline

controlAPI

module function of controlling movement pictures exhibition
module function of controlling iLimb
module funciton of controlling HOH(Hand of Hope)
module function of controlling virtual hand

funs_help

Functions description and parameters settings if necessary.

general

In generally, it is described how these codes are involved into your own project, such as path involvement.

models

Common models functions are described here. For example,

LDA
PCA
ICA
NMF and so on.

Explanations on TCPIP parameters

Common

HOST_IP=127.0.0.1 50040 or something like that properties of tcpip LocalHost = '127.0.0.1' LocalPort = 50040
InputBufferSize, BytesAvailableFcnMode BytesAvailableFcnCount BytesAvailableFcn

EMG

InputBufferSize = 6400 BytesAvailableFcnMode = 'byte' BytesAvailableFcnCount = 1728 BytesAvailableFcn , @Function when the cache in LocalHost:LocalPort is acquried enough to 1728bytes, Function is trigged.
why 1728 1728 = (27 samples)x(4 bytes/sample)x(16 channels)

ACC

InputBufferSize = 6400 BytesAvailableFcnMode = 'byte' BytesAvailableFcnCount = 384 BytesAvailableFcn , @Function when the cache in LocalHost:LocalPort is acquried enough to 1728bytes, Function is trigged.
why 384 384 = (2 samples)x(4 bytes/sample)x(48 channels) 3-axes: x-y-z 16 channels
27:2, is the simplest proportion

Summary of TCPIP on EMG&ACC

All data from 16 channels, including EMG signal and ACC data, are stored in the tcpip cache.

In your self-defined functions, you should seperate your wanting data that relating to the selected Sensor channels.

Select the right data to update plotting or stored in the .txt or csv files.

A common error about TCPIP

Error Messages as following:

Error using icinterface/fread (line ...)
OBJ must be connected to the hardware with FOPEN.

Error in Model/NotifyEMG (line ...)
    data = cast(fread(obj.interfaceObjects{2},bytesReady), 'uint8');

Error in Model>@(varargin)obj.NotifyEMG(varargin{:}) (line ...)
    'BytesAvailableFcn', {@obj.NotifyEMG}) ...
Error instrcb (line ...)
    feval(val{1}, obj, eventStruct, var{2:end});

原因分析：根本原因在于MATLAB里面没有中断优先级的机制。也就是当前执行的任务，无论如何都要执行完毕。然后，当CPU空闲的时候，就去查中断的堆栈，如果堆栈中有来自某个的中断请求，CPU就回去执行；只要有任何一方提中断，就会将响应地址写到中断向量的堆栈中，等CPU来响应。

所以，就有可能产生一个矛盾，（针对当前的情况分析如下）因为某一个函数执行时间比较长，在此期间TCPIP中断已经提了20个中断，都被压在堆栈中了；正常情况下当该函数被执行完毕后，就去逐一执行堆栈中的中断；而恰恰不巧的是，在执行该函数的过程中，其中有些命令直接把TCPIP端口关闭了，啊？此时，中断的堆栈中竟然还有TCPIP的中断请求，好吧，函数执行完毕后，去响应TCPIP中断请求，不巧的是，TCPIP已经关闭了，怎么办呢？就报错呗，要求用FOPEN进行设备连接，也就错误提示的第一句话。

cnzero / sEMG_SDK