是HOST功能更强还是OTG 呢? 大显ＣＵ９２８的串口RS232的针脚定义 1 CAR_MIC_IN 2 GND 3 CAR_AUDIO_R 4 CAR_AUDIO_L 5 GND 6 RS232_DCD 1 7 RS232_CTS 8 8 RS232_TXD 3 9 RS232_RTS 7 10 RS232_RXD 2 11 RS232_DTR 4 12 NC 13 USB_VDD 14 UDC+ 15 UDC- 16 GND 17 GND 18 GND 19 CAR_ON# 20 V_ADP 21 V_ADP 22 V_ADP