Hello Everyone
i am making a data logger which stores data to a serial eeprom.
i want to know how i can make my data logger go into download mode when i plug the 9 Way D type cable to a PC
i am using Hardware uart on the PIC16f877 and i can use Hserout to download the data stored to my eeprom by pressing a push button which then jumps to my download sub.
The problem is that the unit the logger is going into would not have a push button the user should be able to go into download mode when the pc cable is plugged in.
How can i do this?
Also because i would also be using a bootloader is there a way of doing this with just 3 wires TX,RX & Gnd/


Toni