Hello Tobias,
Thanks for the reply. I am trying to send a set of numbers from one PC to the other using USB6501. To do so, I use 2 lines handshaking and 8 lines for coding numbers. I send a number as float. Therefore, I need to send a signal with 8 lines 4 times, in order to send one float.
My protocole goes as follows:
- Set the 8 lines output from the sender which code a number of parameters to be sent
- Set the output line of handshaking of the sender at High
- The receiver reads the High signal from the sender and read the 8 lines, to get a number of parameters to be sent.
- The receiver set its output line of handshaking at High. The sender reads this signal and, then, set the output line of handshaking of the sender at Low.
- The receiver reads the Low signal from the sender and, then, set the output line of handshaking at Low.
- The sender send the first 8 bit of the first number to be sent. The process essentially goes back to 1
The code snippets are attached below.
Sender:
void EventPulse::run()
{
int i,nPara, ind, sig;
bool onBefore=false;
readyToSend=true;
cout<<"EvPulse::run() before while(1), readyToSend="<<readyToSend<<", paramReceived ="<<paramReceived<<endl;
while(1){
if (paramReceived && readyToSend){
nPara = paramVec.size();//# of parameters
intToBinarySeq(nPara);
error = DAQmxWriteDigitalLines(taskHandle_para,1,1,10.0,DAQmx_Val_GroupByChannel,parameter,NULL,NULL);
qDebug()<<"EvPulse::run (sender) redyToSend="<<readyToSend<<endl;
setPulse(1);
readyToSend = false;
i=0;
while (i < numRepSend*nPara){
if(readyToSend){
ind = i/numRepSend;
floatToBinarySeq(paramVec[ind], i%numRepSend);
error = DAQmxWriteDigitalLines(taskHandle_para,1,1,10.0,DAQmx_Val_GroupByChannel,parameter,NULL,NULL);
readyToSend = false;
setPulse(1);
i++;
}
else if(!readyToSend){
if ( checkHandShake() == 1 && !onBefore){
setPulse(0);
//wait until checkHanshake()==0
while( checkHandShake() == 1 ){
msleep(50);
}
readyToSend = true;
}
else if( checkHandShake() == 0 )
onBefore = false;
}
//after sending all the params, make the stim pc
//to get out of the loop for receiving parmas
if (i == numRepSend*nPara)
{
//wait until checkHandshake==1
while( checkHandShake() == 0 ){
msleep(50);
}
setPulse(0);
}
}
paramReceived = false;
emit paramsSent();
break;
}
}
}
Reciever
void ReceiveParameters::run(bool &ok)
{
int i,numPara, n;
numSeq.clear();
initialize();
ok = false;
flagRead=false;
stringstream ss;
error = DAQmxStartTask(taskHandle_in);
error = DAQmxStartTask(taskHandle_out);
error = DAQmxStartTask(taskHandle_para);
error = DAQmxReadDigitalLines(taskHandle_in,1,10.0,DAQmx_Val_GroupByChannel,data,2,&read,&bytesPerSamp,NULL);
if (data[0]==1)
flagRead = true;
while ( flagRead == true ){
error = DAQmxReadDigitalLines(taskHandle_in,1,10.0,DAQmx_Val_GroupByChannel,data,2,&read,&bytesPerSamp,NULL);
if ( flagGotPara == false && data[0]==1){//If parameter lines are set and paramters are not acquired yet
error = DAQmxReadDigitalLines(taskHandle_para,1,10.0,DAQmx_Val_GroupByChannel,para,sizePara,&read,&bytesPerSamp,NULL);
numPara = binaryToInt();
cout<<"# of parameters="<<numPara<<endl;
flagGotPara = true;
setPulse(1);
i=0;
while (i < numRepSend*numPara){
error = DAQmxReadDigitalLines(taskHandle_in,1,10.0,DAQmx_Val_GroupByChannel,data,2,&read,&bytesPerSamp,NULL);
if(data[0]==0 && flagGotPara==true){
flagGotPara=false;
setPulse(0);
cout<<"RecvPara::run(), data[0]="<<int(data[0])<<", flagGotPara="<<flagGotPara<<endl;
}
if(data[0]==1 && flagGotPara==false){
error = DAQmxReadDigitalLines(taskHandle_para,1,10.0,DAQmx_Val_GroupByChannel,para,sizePara,&read,&bytesPerSamp,NULL);
storeBinary(i);
i++;
flagGotPara=true;
setPulse(1);
}
}
ok = true;
stop();
}
else if (data[0]==0){
flagGotPara = false;
dat_out[0]=0;
error = DAQmxWriteDigitalLines(taskHandle_out,1,1,10.0,DAQmx_Val_GroupByChannel,dat_out,NULL,NULL);
}
}
}
