Thread Subject: Getting single value from serial port

Hi Everybody,

I am using a PIC chip interfaced to computer via a wireless
chip and USB-to-serial adaptor. The PIC chip is sending data
in a serial format from four sensors one by one (e.g.
sensor1 sensor2 sensor3 sensor4) with every value separated
by \n\r.

When I read this data on my hyperterminal, data is appearing
totally fine. I even made it appear fine on matlab using the
following code:


instrreset
s = serial('COM8');
set(s,'BaudRate',9600,'DataBits',8,'StopBits',1,'Parity',
'none','Terminator','CR/LF','InputBufferSize',1024);
fopen(s);

while(1)
    fprintf(s, '*IDN?');
    sensor1 = fscanf(s)
% fprintf(s, '*IDN?');
% sensor2 = fscanf(s)
% fprintf(s, '*IDN?');
% sensor3 = fscanf(s)
% fprintf(s, '*IDN?');
% sensor4 = fscanf(s)
end

fclose(s);
delete(s);
clear s;


However if I try to uncomment the above lines, data goes in
huge bunches to every variable. However I wanted every
consecutive value to go to different variables.

I have tried fscanf(s,'%u',3), but it starts giving out
wrong values somehow.

Can you suggest me a way to do this?

It is kind of urgent for my project.

Thanks a lot.
Grace

In article <fnue9r$f0p$1@fred.mathworks.com>,
Grace <gracee@mathworks.com> wrote:
>s = serial('COM8');
>set(s,'BaudRate',9600,'DataBits',8,'StopBits',1,'Parity',
>'none','Terminator','CR/LF','InputBufferSize',1024);
>fopen(s);
[...]
> sensor1 = fscanf(s)
[...]

Matlab does not document the meaning of calling fscanf()
without providing a format string. I cannot predict whether
you are getting a numeric result or a character result in sensor1
--
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