This is an application example using ST Nucleo F103 board. SB62 and SB63 should be soldered. ST-Link/V2 is disconnected (SB13 and SB14). NOTE: Using the USB CDC-ACM for serial communication is a kind of wrong, because it's designed for modem; No way to control CTSRTS. TIOCGICOUNT TODO: * SEND_BREAK support * Use of DMA for serial communication * RS-232 support: GPIO with DTR (out), DCD (in), DSR (in), RI (in) * serial config setting of CTSRTS? By vendor specific control? * stats report control By vendor specific control? * Half-duplex support * Support of other communication mode: smartcard, IrDA, etc.