I am a retired electronic technician and I am creating a photovoltaic energy system for my use.
It works at 48v with 4 batteries in series. Each battery has its own charger, which I built, which receives power from its own panel.
With this I aim to always have the batteries equalized and the system works.
My problem begins when trying to send the charging data of these batteries to a PC, to record the evolution.
The data is collected by a uP and sent by Bluethoot with a BT-909 module.
These are received with another BT-909 module connected to a USB port of a PC, and an Excel sheet reads them.
To do this, I have used the modCOMM library implemented in an Excel sheet, which I found on the internet.
I'm not an expert in VBA, but I've gotten the system to work.
However, when I first try to connect the USB module to the Excel sheet, IT DOES NOT WORK and I get no response.
However, if the first connection was made through Coolterm and I sent AT to the BT909 module, it responds correctly, sending "OK". In this situation, without disconnecting the BT909 module from the port, I disconnect Coolterm and open and connect the Excel sheet, the transmissions are carried out correctly.
Could you give me some idea about what can happen in that first connection???
The truth is that I don't know where to go next and I don't know anyone who can help me...
I attach a pdf with screenshots of the process and the spreadsheet is half built, but with the communications completed.
Thanks and sorry for disturb
Joan Martí
It works at 48v with 4 batteries in series. Each battery has its own charger, which I built, which receives power from its own panel.
With this I aim to always have the batteries equalized and the system works.
My problem begins when trying to send the charging data of these batteries to a PC, to record the evolution.
The data is collected by a uP and sent by Bluethoot with a BT-909 module.
These are received with another BT-909 module connected to a USB port of a PC, and an Excel sheet reads them.
To do this, I have used the modCOMM library implemented in an Excel sheet, which I found on the internet.
I'm not an expert in VBA, but I've gotten the system to work.
However, when I first try to connect the USB module to the Excel sheet, IT DOES NOT WORK and I get no response.
However, if the first connection was made through Coolterm and I sent AT to the BT909 module, it responds correctly, sending "OK". In this situation, without disconnecting the BT909 module from the port, I disconnect Coolterm and open and connect the Excel sheet, the transmissions are carried out correctly.
Could you give me some idea about what can happen in that first connection???
The truth is that I don't know where to go next and I don't know anyone who can help me...
I attach a pdf with screenshots of the process and the spreadsheet is half built, but with the communications completed.
Thanks and sorry for disturb
Joan Martí
