I have built a arduino midi octapad with a Clone of arduino nano that contain a ch340 chip but hairless midi says FTDI driver doesn't installed i installed that driver but it still show that error so can i replace the ch340 chip with a FTDI chip to resolve this Problem... ?
When you search for "FTDI" in one of the hairless-midiserial repos on github (I looked at this and this one), you find what looks like your error message (though you didn't actually put it in your question:
./src/PortLatency_win32.cpp: emit debugMessage("FTDI drivers don't seem to be installed. Not attempting any FTDI latency tricks.");
Also the repos have a class in PortLatency.h with the description:
A simple class to manage latency reduction of FTDI-based serial ports.
This gives us some information:
- The message above is not an error message, but a debug message. It might work despite not having an FTDI
- The class description suggests, that the program wants to use some tricks to reduce the latency in the communication. These tricks seem to be FTDI specific. When the above debug message appears, these tricks are not used. Thus your performance may be significantly worse than with an FTDI chip. Also one of the repos has an open issue about problems with the CH340, which states, that it just doesn't work correctly. It was updated in May and still has no solution. I would not bet on getting help there. (Also the ground repo, that the other was forked off, wasn't updated since 5 years.)
- You cannot fix that debug message by installing the FTDI drivers, because you don't use an FTDI chip.
As we are on Arduino SE here, we cannot really help you with that program running on your PC.
Of course you can use an extra FTDI chip/board and connect it to the RX and TX lines of the Arduino (not using the CH340 USB serial chip on the Arduino itself). But I support Majenkos comment about just migrating to an Arduino with native USB connection (means the USB communication is done by the Arduinos microcontroller directly, not by an extra chip) (for example the Micro, but there are a lot more Arduinos with native USB). That enables you to manipulate the type of USB connection, thus you can let the Arduino directly appear and work as an USB midi device. Then you don't need the hairless-midiserial program anymore.