External Trigger (digitalio) Problems

1
I need to send an external trigger from my computer to a TMS Magstim device.

I have previously 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!