The default serial port /dev/ttyS0 at MMIO 0x1c28000, used for (bootstrap) debugging and the serial console, is located at J11 - refer to the picture and instructions below. The Raspberry's «original» serial port on GPIO 14 and 15 (CON3, pins 8 and 10 - at MMIO 0x1c28c00) can usually be accessed as /dev/ttyS2 on the Banana Pi. J12 also provides another serial port on pins 4 (RXD) and 6 (TXD) at MMIO 0x1c29c00, which should map to /dev/ttyS3.
Просмотр портов которые были инициализированны при загрузке.
# dmesg | egrep "serial|uart" [ 0.624573] [uart]: used uart info.: 0x9d [ 0.629284] [uart]: serial probe 0 irq 33 mapbase 0x01c28000 [ 0.655568] sunxi-uart.0: ttyS0 at MMIO 0x1c28000 (irq = 33) is a U6_16550A [ 1.268216] [uart]: serial probe 2 irq 35 mapbase 0x01c28800 [ 1.300063] sunxi-uart.2: ttyS1 at MMIO 0x1c28800 (irq = 35) is a U6_16550A [ 1.311884] [uart]: serial probe 3 irq 36 mapbase 0x01c28c00 [ 1.343707] sunxi-uart.3: ttyS2 at MMIO 0x1c28c00 (irq = 36) is a U6_16550A [ 1.355513] [uart]: serial probe 4 irq 49 mapbase 0x01c29000 [ 1.387328] sunxi-uart.4: ttyS3 at MMIO 0x1c29000 (irq = 49) is a U6_16550A [ 1.399127] [uart]: serial probe 7 irq 52 mapbase 0x01c29c00 [ 1.430931] sunxi-uart.7: ttyS4 at MMIO 0x1c29c00 (irq = 52) is a U6_16550A [ 15.832308] usbcore: registered new interface driver usbserial [ 15.856278] usbcore: registered new interface driver usbserial_generic [ 15.896370] usbserial: USB Serial Driver core
Ссылки:
http://linux-sunxi.org/LeMaker_Banana_Pi
http://forum.banana-pi.org/t/bpi-m1-uart3-ttys2-not-working/681