Hi all

First post, so be gentle with me :)

I have been using Perl for many years with too much trouble, but I have only recently had to deal with Win32::OLE.

I am trying to control a Phidget USB Display board via Perl ( http://www.phidgets.com/products.php?category=15&product_id=1203 )

So far, no problems opening the device via OLE, and obtain the board serial number, set the backlight and cursor blink.

use Win32::OLE;

$phidget = Win32::OLE->new("Phidget21COM.PhidgetTextLCD");
$phidget->Invoke("Open", -1);

(check/wait loop here for "IsAttached")

$serial = $phidget->{SerialNumber};

$phidget->{"Backlight"} = 1;
$phidget->{"CursorBlink"} = 0;

[download]

but, when I try to set the text in the LCD display, I am having really issues trying to work out the VB to Perl equivalent of this:

TextLCD.DisplayString(0) = "hello"

[download]

where "TextLCD" is the "$phidget" OLE object I have opened. I have tried just about everything I can think of, and must be missing something really obvious:

#does nothing
$phidget->Invoke('DisplayString', (1,"hello"));
$phidget->Invoke('DisplayString', (2,"goodbye"));

#again, does nothing
$phidget->{"DisplayString"} = (1,"hello");
$phidget->{"DisplayString"} = (2,"goodbye");

#still does nothing
$phidget->DisplayString(1, "hello");
$phidget->DisplayString(2, "goodbye");

#This still does nothing
$phidget->{DisplayString}[0] = "hello";

[download]

If it runs, it does nothing. If it doesnt run, it spits out:

Win32::OLE(0.1707) error 0x8002000e: "Invalid number of parameters"
    in PROPERTYPUT "DisplayString" at phidget-test.pl line 30

[download]

Is there anyone here at the Monastery who can enlighten me to my glaring mistake?

In reply to Win32::OLE / Perl / Phidget Display code by SteveL

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