HELP! ilrd() problem in VB

[Anonymous]

I'm having trouble in VisualBasic with an HP DMM using the GPIB cmd :
ilrd(Dev%,ValueStr$,Len(ValueStr$)).
I'm pretty sure it's how I've dimensioned ValueStr$. What is the
proper way?
I've also seen the call used like:
ilrd(Dev%,ValueStr,Len(ValueStr)). No $ signs. Whats the difference?

my code uses:
Dim ValueStr As String
Dim Dev As integer
Also, what does the $ at the end of ValueStr mean, and the % on Dev?

[ScottieB]

Check out the VB examples that ship with our driver.  These are usually located in C:\Program Files\National Instruments\NI-488.2\Languages\Visual Basic

Scott B.
GPIB Software

National Instruments

[gpibtester]

In answer to the second question:

"Also, what does the $ at the end of ValueStr mean, and the % on Dev?"

The $ is the identifer for a string variable and % is the identifier for an integer variable.

Hope this helps clear it up.

[Makoto]

You must allocate enough buffer for the string variable before ILRD() or IBRD() call.  Just declaring a string variable with Dim ValueStr As String does not allocate any buffer and its default length is zero.

...

Dim ValueStr As String

ValueStr = SPACE(256)

status = ilrd(Dev,ValueStr,Len(ValueStr))

% specifies Integer type and $ specifies String type.  This style has been kept unchanged since GW-BASIC era. 

Dim X As Integer and Dim X% are the same for declaring an Integer, however Dim X declares Variant type.

[Anonymous]

On Fri, 17 Mar 2006 11:41:48 -0600 (CST), Makoto <x@no.email> wrote:

>You must allocate enough buffer for the string variable before ILRD() or IBRD() call.&nbsp; Just declaring a string variable with Dim ValueStr As String does not allocate any buffer and its default length is zero.
>&nbsp;
>..
>Dim ValueStr As String
>ValueStr = SPACE(256)
>status = ilrd(Dev,ValueStr,Len(ValueStr))
>&nbsp;
>% specifies Integer type and $ specifies String type.&nbsp; This style has been kept unchanged since GW-BASIC era.&nbsp;
>&nbsp;
>Dim&nbsp;X As Integer and Dim X% are the same for declaring an Integer, however Dim&nbsp;X declares Variant type.
>&nbsp;

Thanks, this is what I needed:

Const ARRAYSIZE = 1024
Dim ValueStr As String * ARRAYSIZE

and I found out that Dim Count% is the same as Dim Count As Integer,
$, string...

[Anonymous]

On Fri, 17 Mar 2006 09:41:44 -0600 (CST), ScottieB <x@no.email> wrote:

>Check out the VB examples that ship with our driver.&nbsp; These are usually located in C:\Program Files\National Instruments\NI-488.2\Languages\Visual Basic
>&nbsp;
>Scott B.GPIB Software
>National Instruments
Thanks, that just what I did and foun the problem!!!