MATLAB DAQ External Trigger (digitalio) Not Working

I need to send an external trigger from my computer to a TMS Magstim device.

I have been advised that this is the code I need:

 dio = digitalio('parallel','LPT1');
 addline(dio,0:7,0,'out');
 line = 1;
 % Set value to 0 (low)
 putvalue(dio.line(line),0);
 % Set value to 1 (high)
 putvalue(dio.line(line),1);
 % Set value to 0 (low)
 putvalue(dio.line(line),0);

However it doesn't seem to work! The code produces these lines:

    Display Summary of DigitalIO (DIO) Object Using 'PC Parallel Port Hardware'.

    Port Parameters:  

    Port 0 is port configurable for reading and writing.
    Port 1 is port configurable for reading.
    Port 2 is port configurable for reading and writing.

      Engine status:  Engine not required.

DIO object contains line(s):

Index:  LineName:  HwLine:  Port:  Direction:  
1       'Pin2'     0        0      'Out'       
2       'Pin3'     1        0      'Out'       
3       'Pin4'     2        0      'Out'       
4       'Pin5'     3        0      'Out'       
5       'Pin6'     4        0      'Out'       
6       'Pin7'     5        0      'Out'       
7       'Pin8'     6        0      'Out'       
8       'Pin9'     7        0      'Out'

But nothing happens on the machine end, even though it's set up to run.

If anyone has any advice I would be grateful!