Overview

This chapter describes how to set up ADB (Android Debug Bridge) and GDB (GNU Project Debugger) environments on PC and target board.

ADB

The ADB is a versatile command-line tool that lets you communicate with a device. The adb command facilitates a variety of device actions, and it provides access to a Unix shell that you can use to run a variety of commands on a device. It is a client-server program including three components:

Client: sends commands. The client runs on your development machine.
Daemon (adbd): runs commands on a device. The daemon runs as a background process on device.
Server: manages communication between the client and the daemon. The server runs as a background process on your development machine.

Setup ADB Environment on Host

ADB is included in the Android SDK Platform-Tools package, which can be downloaded from Adroid Studio SDK build tools.

Windows

Download ADB on PC.
Setup environment variable on PC.
1. Right-click on This PC, and choose Properties > Advanced system settings > Environment Variables….
2. Edit Path to create a new environment variable and input the ADB path (adb.exe is in platform-tools, such as D:\adb\aosp-sdk-platform-tool), then save it.
Check ADB environment on host.

Open Windows command line, input adb –help. If ADB version and global options is shown, the environment on host is OK.

Linux

Download ADB to host.

Export ADB path to shell environment.

export PATH=/xyz/platform-tools/bin:$PATH to .bashrc

Setup ADB Environment on Board

The adb supports both TCP/IP and USB protocol that enable you debug the target device with Wi-Fi or USB line.

USB Mode

Connect host and target board with USB cable and set device to USB mode.
Switch USB mode and start adbd daemon on target board by executing /bin/usb.sh usbd_adb.
```
$/bin/usb.sh usbd_adb
```

TCP/IP Mode

Setup Wi-Fi connection and ensure that ping between host and target board is OK.
Start adbd daemon on target board.
```
/bin/adbd &
```

How to Use ADB

Connect ADB

USB Mode

After executing command above on board, host can use command adb devices to show the connected device.
TCP/IP Mode

Connect the target device with command adb connect. After successful connection, host can use command adb devices to show the connected device.
```
$adb connect <board_ip>:5555
$adb devices
```

ADB Commands

Command adb --help on host can show all ADB commands, which are listed below.

adb devices:

shows the connection states of all devices.

adb start-server:

starts ADB server.

adb kill-server:

stops ADB server.

adb connect ip:5555:

connects devices for TCP/IP mode.

adb push <local> <remote>:

pushes the specific file from host to device.

<local>:: indicates the file position stored in host.
<remote>:: indicates the destination needed to be pushed to the board.

For example:

$adb push ~/system/lib/libfoo_bar.so /lib/

adb pull <remote> <local>:

pulls the specific file from device to host.

<remote>:: indicates the file on board needed to be copied to host.
<local>:: indicates the position to store the file in host.

For example:

$adb pull /lib/libfoo_bar.so ~/system/lib/

adb shell:

Window command line or Linux shell can enter device command line. Use exit to return to Window command line or Linux shell.

fastboot

The fastboot protocol is a mechanism for communicating with boot over USB. It is designed to download the images to the Flash. Generally, images are stored in flash and then loaded to RAM to boot system. The fastboot allows user to download images to ram and reboot it, or to burn images to the Flash.

This section describes how to download the image to target board RAM with fastboot.

Setup fastboot Environment on Board

To enable fastboot in U-boot, the following configuration should be enabled for U-Boot. In SDK, these configurations are enabled by default.

CONFIG_FASTBOOT=y
CONFIG_CMD_FASTBOOT=y
USB_FUNCTION_FASTBOOT=y
CONFIG_USB_FUNCTION_FASTBOOT=y
CONFIG_ANDROID_BOOT_IMAGE=y
CONFIG_ANDROID_BOOT_IMAGE_CHECK=n
CONFIG_ANDROID_IMAGE_HEADER_LENGTH=0x800
CONFIG_FASTBOOT_FLASH_NAND=y
CONFIG_FASTBOOT_BUF_ADDR=0x60380000
CONFIG_FASTBOOT_BUF_SIZE=0xF00000
CONFIG_DM_USB_GADGET=y
CONFIG_USB_GADGET=y
CONFIG_USB_GADGET_VENDOR_NUM=0x18D1
CONFIG_USB_GADGET_PRODUCT_NUM=0x4E21
CONFIG_USB_GADGET_MANUFACTURER="realtek"
CONFIG_USB_GADGET_DWC2_OTG=y、
CONFIG_USB_GADGET_VBUS_DRAW=200
CONFIG_USB_GADGET_DOWNLOAD=y

Input any content in time when booting system to enter U-Boot command line mode.

Setup fastboot Environment on PC

Download the fastboot tool for Windows from platform-tools_r34.0.0-windows.zip and unzip it, start a command window and switch to the directory where the fastboot program is located.

How to Use fastboot

Start fastboot on the U-boot of the target board.
```
=> fastboot usb 0
```
Start fastboot client on PC, input command fastboot.exe devices, If the following information is displayed, fastboot runs success.
```
=> fastboot.exe devices
0123456789AB  fastboot
```

Continue to input command fastboot.exe boot d:kernel.img to load kernel image to RAM. It will display as follows.

=> fastboot.exe boot D:\kernel.img
creating boot image...
creating boot image - 3596288 bytes
Sending 'boot.img' (3512 KB)                       OKAY [  0.111s]
Booting                                            OKAY [  0.000s]
Finished. Total time: 0.549s

The uboot will show below log, which means download to ram status, and boot from the ram address

=> fastboot usb 0
Starting download of 3596288 bytes
...........................
downloading of 3596288 bytes finished
Booting kernel at 0x60380000...
## Booting kernel from Legacy Image at 60380000 ...
Image Name:   Linux-5.4.63
Created:      2023-03-08  11:59:51 UTC
Image Type:   ARM Linux Kernel Image (uncompressed)
Data Size:    3593416 Bytes = 3.4 MiB
Load Address: 60388000
Entry Point:  60388000
Verifying Checksum ... OK
Loading Kernel Image ……

For more details about fastboot, refer to Android-specific doc.