Px4 system terminal for pixhawk

Version Description ：

1. Self driving instrument ：Holybro Of Pixhawk 4.

2. PX4 edition ：1.13

3. The host machine ：Thinkpad The notebook +Ubuntu 20.04.2 LTS

Reference resources ：PX4 Consoles/Shells | PX4 User Guide

One . Making hardware interface

This interface is 3 Root line , take PC The machine USB Serial port and Pixhawk Serial port （ Also called Debug port） Connect .

1. understand Pixhawk 4 Yes IO Debug Interface and FMU Debug Definition of interface

PIXHAWK 4 There are two Debug Port, One is IO Debug Port, The other is FMU Debug Port. Both ports provide Pixhawk standard 6-Pin SH Debug Port.（6 The needle ）

2. take Pixhawk 4 Of FMU Debug Port With the host USB The mouth is connected

In order to realize the system terminal , The host machine USB Need to be connected to a FTDI On the converter （FTDI Yes, it will USB A device that converts a port into a serial port ）, I'm buying Pixhawk 4 Of the wire package Debug Port Adapter wire of （ See the picture below ）, This wire is made of 6 The root line connects the two adapters , Can be cut from the middle , A system terminal interface , The other can be used to do J-Link Interface .

stay 6 Select... From the root line 3 Root line and FTDI The pins of the ,3 How to choose the root line , See the table below ：

FMU Debug Port	FTDI
1 Vtref	-
2 Console TX	5
3 Console RX	4
4 SWDIO	-
5 SWDCLK	-
6 GND	1

The finished 3 Root line will FTDI（ Right connection FTDI DuPont head is used for stitching ） And FMU Debug Port Adapter port of （ White on the left ） Connect , See the picture below .

  Two . Software part

1. stay Ubuntu End installation screen Software ：

sudo apt-get install screen

2. Connection interface , start-up Pixhawk

Connect one end of the interface to PC Machine connection , The other end is with Pixhawk 4 Of FMU Debug Mouth connection , Then start Pixhawk.

3. function screen command  

 Open one linux terminal , Run the following command   screen /dev/ttyXXX BAUDRATE 8N1

here ttyxxx choice ttyACM1 perhaps ttyUSB0. baudrate choice 57600, such as ：

sudo screen /dev/ttyUSB0 57600 8N1

here , stay screen ... appears in the interface "nsh>" Prompt , Can run nuttx command .

If you unplug the connection Pixhawk Of USB Connecting line , Then put on , You'll see PX4 stay Pixhawk Start sequence information on , Here's the picture ：