raspberry pi pin layout

Raspberry Pi native Serial port default for console output, if you want to use in your own program need to shut down the system to occupy this serial port. The method is configured for Rasp-config, or directly modifies the/boot/cmdline.txt #dwc_otg. lpm_enable=0 console=tty1 console=serial0,115200 root=/dev/mmcblk0p2 rootfstype=ext4 elevator= Deadline Fsck.repair=yes Rootwai Dwc_otg.lpm_enable=0 console=tty

that the appropriate content is modified according to the actual situation: [Unit] Description=wireless Static IP Connectivity Wants=network.target Before=network.target [Service] Type=oneshot Remainafterexit=yes Environmentfile=/etc/conf.d/wifi EXECSTART=/SBIN/IP Link Set Dev wlan0 up EXECSTART=/SBIN/IP addr Add 192.168.34.1/24 broadcast 192.168.34.255 Dev Wlan0 EXECSTOP=/SBIN/IP addr Flush Dev Wlan0 EXECSTOP=/SBIN/IP Link Set Dev