# Serial > In telecommunication and computer science, serial communication is the process of sending data one bit at a time, sequentially, over a communication channel or computer bus. This is in contrast to parallel communication, where several bits are sent as a whole, on a link with several parallel channels. [Wikipedia](https://en.wikipedia.org/wiki/Serial_communication) * [Intel Edison: using UART ttyMFD1 serial port](https://scivision.co/intel-edison-using-uart-ttymfd1-serial-port/) * [Using USB-serial FTDI adapters with Intel Edison](https://scivision.co/using-usb-serial-ftdi-adapters-with-intel-edison/) * [Intel Edison Types of Serial Ports](https://communities.intel.com/thread/54236) * [Sparkfun Serial Terminal Basics](https://learn.sparkfun.com/tutorials/terminal-basics/all) * [TLDP Serial HOWTO](http://www.tldp.org/HOWTO/Serial-HOWTO.html) * [Linux Journal Greg Kroah-Hartman The Serial Driver Layer](http://www.linuxjournal.com/article/6331) ## Kernel Integration ### Kernel Display Message ```bash root@edison:~# dmesg | grep -i serial [ 0.000000] Kernel command line: rootwait root=PARTUUID=012b3303-34ac-284d-99b4-34e03a2335f4 rootfstype=ext4 console=ttyMFD2 earlyprintk=ttyMFD2,keep loglevel=4 g_multi.ethernet_config=cdc systemd.unit=multi-user.target hardware_id=00 g_multi.iSerialNumber=5e7bb54a65035af180191c2d7bd527b6 g_multi.dev_addr=02:00:86:d5:27:b6 platform_mrfld_audio.audio_codec=dummy [ 0.704157] HSU serial 0000:00:04.0: FUNC: 0 driver: 0 addr:ff010000 len:80 [ 0.704215] HSU serial 0000:00:04.1: FUNC: 1 driver: 0 addr:ff010080 len:80 [ 0.705663] HSU serial 0000:00:04.2: FUNC: 2 driver: 0 addr:ff010100 len:80 [ 0.707102] HSU serial 0000:00:04.3: FUNC: 3 driver: 0 addr:ff010180 len:80 [ 0.744061] usbcore: registered new interface driver usbserial [ 0.744199] usbserial: USB Serial support registered for pl2303 [ 3.758915] systemd[1]: Starting system-serial\x2dgetty.slice. [ 3.833730] systemd[1]: Created slice system-serial\x2dgetty.slice. root@edison:~# dmesg | grep -i tty [ 0.000000] Kernel command line: rootwait root=PARTUUID=012b3303-34ac-284d-99b4-34e03a2335f4 rootfstype=ext4 console=ttyMFD2 earlyprintk=ttyMFD2,keep loglevel=4 g_multi.ethernet_config=cdc systemd.unit=multi-user.target hardware_id=00 g_multi.iSerialNumber=5e7bb54a65035af180191c2d7bd527b6 g_multi.dev_addr=02:00:86:d5:27:b6 platform_mrfld_audio.audio_codec=dummy [ 0.705116] 0000:00:04.1: ttyMFD0 at MMIO 0xff010080 (irq = 28) is a hsu_bt_port_p [ 0.706565] 0000:00:04.2: ttyMFD1 at MMIO 0xff010100 (irq = 29) is a hsu_uart1_port_p [ 0.707871] 0000:00:04.3: ttyMFD2 at MMIO 0xff010180 (irq = 54) is a hsu_uart2_port_p [ 0.713301] console [ttyMFD2] enabled [ 1.969453] Bluetooth: RFCOMM TTY layer initialized [ 2.776422] systemd[1]: Expecting device dev-ttyMFD2.device... [ 3.758915] systemd[1]: Starting system-serial\x2dgetty.slice. [ 3.833730] systemd[1]: Created slice system-serial\x2dgetty.slice. [ 3.833870] systemd[1]: Starting system-getty.slice. [ 3.883637] systemd[1]: Created slice system-getty.slice. ``` ## Userspace Interfaces ### Sysfs ```bash root@edison:~# find /sys/ -name 'tty:ttyS*' /sys/devices/pci0000:00/0000:00:04.1/tty /sys/devices/pci0000:00/0000:00:04.1/tty/ttyMFD0 /sys/devices/pci0000:00/0000:00:04.2/tty /sys/devices/pci0000:00/0000:00:04.2/tty/ttyMFD1 /sys/devices/pci0000:00/0000:00:04.3/tty /sys/devices/pci0000:00/0000:00:04.3/tty/ttyMFD2 /sys/devices/pci0000:00/0000:00:12.0/tty /sys/devices/pci0000:00/0000:00:12.0/tty/ttyPTI0 /sys/devices/pci0000:00/0000:00:12.0/tty/ttyPTI1 /sys/devices/virtual/tty /sys/devices/virtual/tty/tty /sys/devices/virtual/tty/tty0 /sys/devices/virtual/tty/tty1 ... /sys/devices/virtual/tty/ttyXX /sys/devices/platform/intel_mcu/tty /sys/devices/platform/intel_mcu/tty/ttymcu0 /sys/devices/platform/intel_mcu/tty/ttymcu1 /sys/devices/platform/intel_mcu/tty/ttymcu2 /sys/class/tty /sys/class/tty/tty /sys/class/tty/tty0 /sys/class/tty/tty63 /sys/class/tty/ttyMFD0 /sys/class/tty/ttyMFD1 /sys/class/tty/ttyMFD2 /sys/class/tty/ttyPTI0 /sys/class/tty/ttyPTI1 /sys/class/tty/ttymcu0 /sys/class/tty/ttymcu1 /sys/class/tty/ttymcu2 /sys/class/tty/ttyGS0 ``` ### Devfs ```bash root@edison:~# ls /dev/tty* /dev/tty /dev/tty2 /dev/tty31 /dev/tty43 /dev/tty55 /dev/ttyGS0 /dev/tty0 /dev/tty20 /dev/tty32 /dev/tty44 /dev/tty56 /dev/ttyMFD0 /dev/tty1 /dev/tty21 /dev/tty33 /dev/tty45 /dev/tty57 /dev/ttyMFD1 /dev/tty10 /dev/tty22 /dev/tty34 /dev/tty46 /dev/tty58 /dev/ttyMFD2 /dev/tty11 /dev/tty23 /dev/tty35 /dev/tty47 /dev/tty59 /dev/ttyPTI0 /dev/tty12 /dev/tty24 /dev/tty36 /dev/tty48 /dev/tty6 /dev/ttyPTI1 /dev/tty13 /dev/tty25 /dev/tty37 /dev/tty49 /dev/tty60 /dev/ttymcu0 /dev/tty14 /dev/tty26 /dev/tty38 /dev/tty5 /dev/tty61 /dev/ttymcu1 /dev/tty15 /dev/tty27 /dev/tty39 /dev/tty50 /dev/tty62 /dev/ttymcu2 /dev/tty16 /dev/tty28 /dev/tty4 /dev/tty51 /dev/tty63 /dev/tty17 /dev/tty29 /dev/tty40 /dev/tty52 /dev/tty7 /dev/tty18 /dev/tty3 /dev/tty41 /dev/tty53 /dev/tty8 /dev/tty19 /dev/tty30 /dev/tty42 /dev/tty54 /dev/tty9 ``` ## Applications / Libraries ### Setup #### Opkg ```bash root@edison:~# opkg install screen Installing screen (4.0.3-r4) on root. ... Configuring screen. root@edison:~# ``` #### Pip ```bash root@edison:~# pip install pyserial Cleaning up... root@edison:~# ``` #### Apt-Get ```bash root@edison:~# apt-get install screen minicom cu setserial stty root@edison:~# pip install pyserial ``` ### Programs ```bash root@edison:~# screen /dev/ttyS0 root@edison:~# minicom /dev/ttyS0 root@edison:~# cu /dev/ttyUSB0 115200 root@edison:~# setserial -g /dev/ttyS[0123] root@edison:~# setserial -g /dev/ttyUSBS[0123] root@edison:~# setserial -g /dev/ttyMFD[0123] root@edison:~# setserial /dev/ttyS0 115200 root@edison:~# stty -F /dev/ttyUSB0 115200 root@edison:~# stty -F /dev/ttyMFD 115200 ``` #### Python ```python #!/usr/bin/python import serial ser = serial.Serial("/dev/ttyMFD0", timeout=10) lines = ser.readlines() for i in range(10): print(lines[i].strip()) ``` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. 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