Serial I/O using kernel32

**IanWade** · 10-31-2011, 06:11 PM

I am trying to get the following (well-known) code working under Excel 2003 and Windows XP:

http://dev.emcelettronica.com/serial...tion-excel-vba

This code is followed by:

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Using a serial line analyzer, I see that nothing happens when pressing CommandButton1. The COM port does not open.

Before I jump in to debug this in detail, a couple of questions:

1. Has anyone here got this code working successfully?

2. Do I have to declare kernel32 somewhere else before this code will work?

(Before anyone asks, I am talking specifically about kernel32. I need to use this for program portability, without the need for the user to install anything else to make it work).

--
Ian

**MarlboroMan** · 11-12-2011, 10:20 AM

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Hi IanWade

I'm using the code you asked about as is with the above mod to the last part of the code to read data from an scale instrument into sheet 1.
The code works fine but need some tweaking to use less resources.
I'm still a noob with VBA but maybe this will help.
Please let me know if you can get it to use less cpu power when reading from the com port.

**Leith Ross** · 11-12-2011, 02:24 PM

Hello IanWade,

Welcome to the Forum!

Kernel32 is the heart of the Windows OS. It is actually a large DLL (Dynamic Link Library) which contains many API (Applications Programming Interface) calls. The Comm calls are but a small number of them.

**IanWade** · 11-12-2011, 03:32 PM

[QUOTE=IanWade;2631949]I am trying to get the following (well-known) code working under Excel 2003 and Windows XP:

(snip)

Before I jump in to debug this in detail, a couple of questions:

1. Has anyone here got this code working successfully?

2. Do I have to declare kernel32 somewhere else before this code will work?
/QUOTE]

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

To answer my own questions:

1. Yes, I have now managed to make it work. For reasons that are still opaque to me, the code only works for COM1 thru COM4. I need to investigate further, but as it is more to do with Windows library parameters rather than Excel, I will look elsewhere for a solution.

2. No, it is not necessary to make references to kernel32, other than those that exist in the code already.

--
Ian