serial data communication, and calculation.?

 p = serial('COM6');
 fopen(p)
 d = 0
 for i = 1:1000
     s = 0
 s = fgets(p)
 t = 1
 d=(s-t)
  if d == 0
      s = 'o'
 elseif d == 1
     s = 'u'
 elseif d == 2
     s = 'w'
 elseif d == 3
     s = 'd'
 elseif d == 4
     s = 'y'
 else
 end
 end

When i run this code, i am getting following output,

 d =    50    12     9

It is obviously wrong. d value should be constant, as i am receiving serial data as either 1 or 2 or 3 or 4 or 5 numerics only.

So, difference will be 0 or 1 or 2 or 3 or 4 respectively.. What is error in code writing.?

Answer 1

[Star Strider]

From the documentation, fgets (serial) returns a line of text from the serial device. The way I read your code, ‘d’ is subtracting 1 from the ASCII representation of the number ‘s’ represents.

See if:

d = (str2num(s) - t)

gives you the result you want.

Note that I cannot test this.

[Nimisha]

Thanks, Its working fine.

[Star Strider]

My pleasure!