Stand-Alone Functions	Purpose
runcont(port,nsample)	start continous data acquisiton
trigger(port)	do a single data acquisition
setchan(port,bit,mode)	set channel mode analog I or digital I/O
output(port,bit,state)	set digital out high or low
showtime(port)	show time settings
showchan(port)	show channel settings
setsamplefast(port,msec)	set sample rate fast mode
setsampleslow(port,min,sec)	set sample rate slow mode
settrigger(port,mode)	set trigger mode internal time, external event
setformat(port,tmode)	set x-axis mode time, count, or none
setsleep(timeout)	set sleep timeout seconds
Subfunctions
serial9600(port)	Create and open serial port object
serialread(spo)	Read serial port buffer until empty
setchansub(port,bit,mode)	set channel mode analog I or digital I/O
cmd(spo,command,delay)	Send command, delay, read reply
cmdb(spo,command,delay)	Same as cmd() but do not print
setsamplefastsub(spo,min,sec)	Set slow sample rate
setsampleslowsub(spo,msec)	Set fast sample rate
runcontsub(spo,count)	read continously, save data to matrix
wakeupsub(spo)	Wake up and return when reply received.

The above codes are structured the following way:

		try				(catches errors and closes serial port)
		{
			cre	ate	se	rial port object, open serial port
			{
	|			one	or	more sub-function(s) consisting of:
	|				A.	send command
main body	|				B.	delay*
	|				C.	read reply or data, test for validity
	|					repeat from A or B if nessessary
			{
			clo	se	por	t, return
		{
		cat	ch	err	or,	print error message, close port, return

*After a command is sent, a delay is required before reading a serial communication reply from SOSI-M2 in order to allow the host serial buffer to receive the reply string. A 0.05 second delay is enough time to allow the string plus terminator to arrive. Commands in which SOSI first writes to non-volitile EEPROM memory before sending a reply require a delay of 0.5 seconds before a read is performed. These commands are:.

'set sample ...' 'set trigger ...' 'set output format ...' 'exit' (from channel menu)

('#sesa ...') ('#set ...') ('#seo ...') ('e')

The main body of stand-alone functions contain the following steps:

1. Function to wake up SOSI or confirm SOSI awake
2. Function to configure the sample rate, sleep timeout, x-axis, or channel mode if nessessary.
3. Function to get data or set a digital bit

One may test run sub-functions from the command line before implementing a longer function. For example,

First, disable sleep mode (using the stand-alone function here):

Open the serial port:


Display the present channel configuration:


Change the output format to print the 'x' axis as sample count:


We are finished for now:


If an M-file contained these commands, enclose the above code in a try-catch block. In the case of an error, the script would otherwise return before the ending fclose(). Placing fclose() in the catch will close the serial port.

If a serial port M-file initially runs but then MATLAB gives the error message:

The serial port was not closed by a previous M-file before the last M-file tried to re-open it. The catch-try code is intended to prevent this. Restart MATLAB to free the port.

Free serial port monitors are available which may be used to monitor opening and closing of the serial port and thereby aid code debugging.

The M-file scripts have been tested working with MATLAB R12 (under Linux) and R14 (under Windows). Certain versions of MATLAB have serial communication issues which may require these steps:

R12 (MS-Windows)


R13 (MS-Windows)