Excel Vba Com Port Communication.

My home auto system has now died.

The server it runs on is 16 years old and has now become unstable. It dies every few hours.

The software, called Touchsoft, only runs on Windows XP and the original deveplopers do not exist anymore/died.

What I have is:

All the wireless switches that are hard-wired to all the devices in the house and operates on the 868 MHz band.

A USB dongle attached to the dysfuntional server on Com port 3 that interprets the data signal from Touchsoft and activates the wireless switches.

A "touch screen" monitor that can plug into any Windows PC. The buttons in Touchsoft are shown on the touchscreen and are activated by touch.

What I have done so far is:

Wrote an Excel VBA front-end with buttons for every device and which shows the state of every button ie ON or OFF.

The Button press ON or OFF can poduce the necessary string/data if I know what format it must be.

What I cannot do yet is:

How to send the string/data to the selected Com port eg Com3.

What the format of the string/data must be in.

PLEASE HELP

 

This sounds like a big under taking if you're not knowledgeable in electronics. Seems like you need to sniff the 868MHz band to capture the message that dongle is sending out to each device and then replay it in a new device (hopefully it is not using encryption / rolling codes). I * think* it would be possible with a software defined radio and a single board computer (Arduino), but you'd need to crack open some books and start learning.
There are a ton of projects that do this with IR so you can make your own remote for example.
https://www.adafruit.com/product/3070
https://learn.adafruit.com/adafruit...5-rfm98-lora-packet-padio-breakouts/downloads


Or it would appear that the USB dongle is just a radio transmitter, maybe capture the data going to the COM port to catch the commands
http://www.sysnucleus.com/USB-Sniffer.html

 

Hi Foogoo, Thanks for your info. Just one point. I have the dongle that can be plugged into a USB port and sends the appropriate signals to the WIFI switches on the 868MHz band. I have written the software UI in Excel VBA that can run on a new Windows based server and send messages to a USB com port. I am hoping that to-day I can get the legacy system to run for a few minutes and log the USB signals going to the dongle for every device ON and OFF.