problem with sending text over serial port.

Hello everyone, I am trying to send a text through RB1100AH serial1 port (the one is inside the case) to my serial device (an LCD).
I´ve already found a script which is suposed to do it, but it does´nt work properly for me.
This is it:

http://wiki.mikrotik.com/wiki/Sending_text_out_over_a_serial_port

And I modified it to use it with a global variable:

[:global output “RouterBOARD 1100AH”
/interface ppp-client add name=“WriteLCD” port=serial1 modem-init=$output null-modem=yes disabled=no
:delay 1
/interface ppp-client remove [/interface ppp-client find name=“WriteLCD”]][/code]

The port and the device are correctly configurated (I can send tex over: [/system serial-terminal serial1][/code]), but with the script is impossible.

I`m using RouterOS Ver. 5.7

There are anyone who know the solution to send text over RB1100AH serial1 with ppp-client?

Thanks.