serial-cmd-dat

CMD

serial output

cat /dev/serial0
cat /dev/ttyAMA0

dmesg

root@raspberrypi:/home/pi/RPI-SDK# dmesg | grep -E "ttyAMA|ttyS"

[    0.000000] Kernel command line: coherent_pool=1M 8250.nr_uarts=0 snd_bcm2835.enable_headphones=0 snd_bcm2835.enable_headphones=0 snd_bcm2835.enable_hdmi=0 snd_bcm2835.enable_hdmi=0  vc_mem.mem_base=0x3ec00000 vc_mem.mem_size=0x40000000  console=ttyS0,115200 console=tty1 root=PARTUUID=06a61d06-02 rootfstype=ext4 fsck.repair=yes rootwait quiet splash plymouth.ignore-serial-consoles cfg80211.ieee80211_regdom=GB isolcpus=3
[    3.103080] 3f201000.serial: ttyAMA1 at MMIO 0x3f201000 (irq = 114, base_baud = 0) is a PL011 rev2
[    3.103429] serial serial0: tty port ttyAMA1 registered

Verify mapping (recommended) == ls -l /dev/serial0

How to read UART now

stty -F /dev/serial0 115200 cs8 -cstopb -parenb
cat /dev/serial0

ref