Diavolino Serial Com
  • Hello,
    Just finished my Diavolino board.
    Is it possible to connect it directly to TTL level COM port on PC(XP) by using TxD, RxD and Reset through D9 connector or I have to go through TTL to USB converter?
    Thanks in advance,

  • I guess I'm not familiar with a "TTL level COM" port, but if it exists, then there should be some way to hook it up.  The FTDI adapter is not strictly necessary, and there are a great many articles out there about programming an Arduino directly from an RS-232 port.   Depending on exactly what your computer has, you may need a level adapter or polarity adapter in order for everything to work correctly.
  • Thanks for your response.
    I even built a level adapter with 2 transistors, based on the Arduino S3v3 Revision 2 schematic that like Diavolino outputs directly RXd, TXd and Reset.
    I then connected Diavolino to normal RS-232c on COM1 (XP).
    It does work and I can upload sketches.
    But  I get the avrdude:stk500_disable():protocol error, expect=0x14, resp=0x00   OR 
                        avrdude:stk500_getsync():not in nsync:resp=0x00

    Any hint would help.