Each test comprises a program that runs in the Basic Stamp 2 and a VB6 program which communicates with it.
The first Stamp 2 program I came up with is listed adjacent.
If you are using the on-board 9–pin serial connector you must specify 16 as the RX (receive) pin in the SERIN command.
84 is Baudmode (see Stamp documentation for SERIN command). mydata is the byte variable that will receive the data from the VB6 program.
Load the Stamp 2 program from the Parallax Basic Editor / Development System.
In this simple program my VB6 program sends an uppercase character A through H to switch on LEDs 0 through 7. I switch them off by sending a corresponding lowercase character a through h.