I am trying to replace a device which used a FTDI chip (http://www.ftdichip.com/Drivers/D2XX.htm) to get USB to serial. I need some more code on the chip, so I want to use an arduino mega 2560 instead. However, there is quite a lot of software which talks to the FTDI-based solution, some of which is not maintained by myself.
Can I write a program for arduino mega which makes it look to the PC software like I am still a FTDI chip? I am somewhat concerned, because the FTDI requires special drivers, so any software will try to use this driver to connect to the arduino, which does not have a chip that is native to the d2xx driver.
PS: If I am not mistaken, arduino used those FTDI chips in the past, but switched to ATmega8u2 for arduino UNO, and to ATmega16U2 for arduino mega 2560.