Re: Streaming Serial Octave

[inertialwave]

Thanks for the answers; I am still investigating but Instrument-Control
within Octave on cygwin is certainly convenient to use; your native Windows
version would be even more convenient :) Wish I could help.

For the record here is a quick cygwin result using the 500 Hz BT serial data
source.
The 15 byte binary data sample protocol is
[$(36) | count(0-199) | followed by 12 bytes of data | \n (10) ]

octave:349> sp = serial("/dev/ttyS23",115200,timeout=3)
sp = 3
octave:350> N=30*500;tic; data = srl_read(sp,N*15);toc
Elapsed time is 28.7106 seconds.  %should be >30 sec.??
...
octave:382> disp(data(1:15))
  214    0   58    0    3   10   36   92  252  160    0    8   58   24  255
octave:385> for
n=[0:10,30:50],disp([n,data(7+n*15),data(8+n*15),data(9+n*15)]),end
    0   36   92  252
    1   36   93  252
    2   36   94  252
    3   36   95  252
    4   36   96  252
    5   36   97  253
    6   36   98  253
    7   36   99  252
    8   36  100  252
    9   36  101  253
   10   36  102  252
   30   36  122  253
   31   36  123  252
   32   36  124  253
   33   36  125  253
   34   36  126  252
   35   36  127  252
   36   36   72  252   %144 samples gap
   37   36   73  252
   38   36   74  252
   39   36   75  252
  40  10  36  89       %14 sample gap + 1 byte shift
  41  10  36  90
  42  10  36  91
  43  10  36  92
  44  10  36  93
  45  10  36  94
  46  10  36  95
  47  10  36  96
  48  10  36  97
  49  10  36  98
  50  10  36  99

As you can see, there still appear to be drop outs in the received data and
tic:toc shows <30 sec. (I can't explain this.) I am experimenting with a
line by line reader with a pause inserted to net ~2 ms line total. 

Similar Python reading of the same BT device shows no drop outs over 30 sec
and tic:toc is a fraction over 30 sec. Python's ability to read what is in
receive buffer (serial.Serial.inWaiting) seems to provide the best
reliability with this source, although, native Octave (e.g. fgets(sp) in a
loop to read line by line) is just about as good with wired serial devices.



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