Application Notes

• System
  • Low power consumption
    • 1. Basic Function Introduction
    • 2. Application Notes
  • Memory application notes
    • 1. Introduction to Basic Functions
      • 1.1 Memory Resources Overview
      • 1.2 Memory Layout
      • 1.3 Typical Application Resource Usage and User Available Resources
    • 2. Application Notes
      • 2.1 Link Script Application Guide (ARMCC Scatter File as an example, other link scripts are similar)
      • 2.2 Calculate the RAM and firmware size used by the program (ARMCC compiler, other compilers can refer to the following method)
        • 2.2.1 GR551x (SDK V2.0.1, user unmodified link script)
        • 2.2.2 GR533x (SDK V1.0.5, user unmodified link script)
  • Introduction to Fault Trace module
    • 1. Fault Trace module introduction
    • 2. Precautions for using Fault Trace Module
  • APP LOG Module Application Notes
    • 1. APP LOG module basic function introduction
    • 2. Notes on APP LOG Module Usage
  • Suggestions for the use of Heap
  • Encryption and Signature
    • 1. Security Solution
    • 2. Tool-side workflow
    • 3. Device-side workflow
    • 4. Tool side (GProgrammer) encryption and signature operation
    • 5. GProgrammer Sign-Only Operation
    • 6. Uncheck Encrypt, only Sign will sign the target Firmware.
  • Introduction to FDS
    • 1. Introduction to FDS
    • 2. NVDS application notes
    • 3. APP FDS Application Notes
    • 4. APP LOG Store Application Notes
• Peripherals
  • I/O
    • I/O Application Notes
      • 1. I/O Basic Functions Introduction
      • 2. I/O Application Notes
  • ADC
    • ADC Application Notes
      • 1. Introduction to ADC Basic Functions
        • 1.1 ADC Function Overview
        • 1.2 Single-Ended Mode Measurement
        • 1.3 Differential Mode Measurement
        • 1.4 How to Select External Reference Voltage for Measurement
        • 1.5 How to Measure Chip Supply Voltage
        • 1.6 How to Measure Internal Chip Temperature
        • 1.7 How to Perform Multi-Channel Measurement
      • 2. Typical ADC Applications
        • 2.1 How to Evaluate Whether the Measurement Range Meets the Requirements
        • 2.2 How to Evaluate Whether the Resolution Meets the Requirements
        • 2.3 How to Improve Measurement Accuracy
        • 2.4 Calibration Method for Selecting Special External Reference Voltage
    • ADC Sampling Rate Test
      • 1. ADC Sampling Clock
      • 2. Testing Sampling Rate
        • 2.1 Required Settings
        • 2.2 Main Test Code
        • 2.3 Testing Results
  • DMA
    • DMA
      • 1. Introduction to Basic Functions
      • 2. Application Notes
  • I2C
    • I2C Application Notes
      • 1. Introduction to GR5xx I2C Basic Functions
      • 2. Typical I2C Applications
        • 2.1 How to Set Slave Address
        • 2.2 I2C Circuit Pull Up Resistor Configuration Considerations
        • 2.3 I2C Working Mode Recommendations
  • I2S
  • SPI and QSPI
    • Topic for SPI and QSPI
      • 01. SPI-QSPI Protocol Special Topic (1) - Introduction to Basic Protocol Features
        • 1. SPI Protocol
          • 1.1 Pin Signals
          • 1.2 Roles
          • 1.3 Clock Frequency
          • 1.4 Clock Modes
          • 1.5 Timing Phase
          • 1.6 SPI Protocol Derived Timing
        • QSPI Protocol
          • 2.1 Overview
          • 2.2 Pin Signals
          • 2.3 Timing Phase
          • 2.4 Instruction Addressing Mode
          • 2.5 QPI Modes
          • 2.6 SIOO Modes
          • 2.7 Efficiency Calculation
      • 02. SPI-QSPI Protocol Special Topic (2) - Fundamentals of Building GR55xx (Q)SPI High-Speed Transmission Interface
        • 1. Basic Application Background Supplement
          • 1.1 System Master and Slave
          • 1.2 Synchronous and Asynchronous Access
        • 2. Data Transmission Behavior
          • 2.1 Writing Data from CPU to Screen via QSPI
          • 2.2 Writing Data via DMA Directly to Screen through QSPI
          • 2.3 Reservoir Problem in Transmission (Producer & Consumer Problem)
      • 03. SPI-QSPI Protocol Special Topic (3) - GR552x Chip’s DMA and QSPI Module Features
        • 1. Typical DMA Features
          • 1.1 Typical DMA Applications
            • 1.1.1 DMA Base Data Transmission
            • 1.1.2 DMA Chain Data Transmission
            • 1.1.3 DMA Scatter Transmission
            • 1.1.4 DMA Gather Transmission
            • 1.1.5 DMA Scatter and Gather Transmission
          • 1.2 Features of DMA Transmission Channel
        • 2. Typical QSPI Features
          • 2.1 QSPI Working Modes
          • 2.2 QSPI Data Endian
            • 2.2.1 Data Endian in Write Operations
            • 2.2.2 Data Endian in Read Operations 2.2.2
            • 2.2.3 Read Rule for Static Data Endian in Memory Mapping Mode
            • 2.2.4 Read Rule for Dynamic Data Endian in Memory Mapped Mode 2.2.4
      • 04. SPI-QSPI Protocol Special Topic (4) - Color Formats and Common Exceptions
        • 1. Screen Color Format
          • 1.1 Common Color Code Formats
          • 1.2 Color Code Format Storage and Usage
        • 2. Analysis of Possible Causes of Out-of-Order Execution
          • 2.1 Inconsistent Read/Write Width of External Flash Leading to Reversal
          • 2.2 Abnormal Byte Order Configuration in Memory Mapped Read of External Flash
          • 2.3 Out-of-Order Due to Unaligned Address in DMA Access
        • 3. Common Display Issues
    • SPI Application Notes
      • 1. Introduction to Basic Functions
      • 2. Application Notes
    • QSPI Application Notes
      • 1. Basic Function Introduction
      • 2. Application Notes
      • 3. Typical Application Scenarios
        • 3.1 GR5526 supports the use of external flash as firmware cache for OTA upgrade.
  • Timer
    • Application Note for Timer and Dual Timer
      • 1. Introduction to Timer and Dual Timer Basic Functions
      • 2. Application Notes for Timer and Dual Timer
    • APP RTC Application Note
      • 1. Introduction to RTC Basic Functions
      • 2. APP RTC Application Note for GR5xx
    • Typical WDT Applications
      • 1. Introduction to GR5xx WDT Basic Functions
      • 2. Typical GR5xx WDT Applications
    • GR5xx Timers
      • 1. Overview of GR5xx Timers
      • 2. Clock configuration of GR5xx slow clock timers
      • 3. RTOS tick implementation of each chip
  • UART
    • UART Application Notes
      • 1. Introduction to UART Basic Functions
      • 2. UART Application Notes
  • USB
    • USB Introduction
      • 1. Introduction to USB
      • 2. Typical USB Applications
  • X-QSPI
    • X-QSPI Application Note
      • 1. Introduction to Basic Functions
      • 2. Application Notes
  • GPU
    • GPU Application Notes
      • 1. Introduction to Basic Functions
        • 1.1 Main Features of GPU
        • 1.2 GPU Usage Key Points
          • 1.2.1 Frame Buffer
          • 1.2.2 Memory Allocation and Usage
          • 1.2.3 Reference Recommendations
      • 2. Application Notes
    • OSPI PSRAM Application Notes
      • 1. PSRAM Address Space Layout and Management
      • 2. Initialization and Usage of PSRAM
      • 3. PSRAM Working Mode
      • 4. PSRAM Sleep Strategy
        • 4.1 Hibernation Strategy in Bare Metal Environment
        • 4.2 Sleep Strategy in RTOS Environment
    • DC Application Note
      • 1. Introduction to Basic Functions
      • 2. Application Notes
• BLE
  • BLE Basicals
    • BLE Broadcasting
      • 1. Introduction to the basic functions of BLE broadcasting
      • 2. Broadcast Application Notes
      • 3. FAQ
        • 3.1 Can the broadcast data be modified all the time?
        • 3.2 How do I turn on two broadcasts at the same time?
        • 3.3 How to enable multi broadcast?
        • 3.4 Is dynamic modification of the broadcast interval supported?
        • 3.5 How to set the broadcast power?
        • 3.6 How to set broadcast for HID device to make system bluetooth display device name?
        • 3.7 How to set the broadcast packet can use 31 Bytes instead of 28 Bytes?
    • BLE Profile
      • 1. Introduction to the basic concept of BLE Profile
      • 2. BLE Profile Application Notes
      • 3. FAQ
        • 3.1 I didn’t add any Service in the sample project, but I can see two Services after connecting to the phone, where do these two Services come from? What are they used for?
        • 3.2 Is there a limit to the number of BLE services that can be created by the chip? What is the maximum number of services that can be supported to be created?
        • 3.3 Execute ble_gattc_prf_read and the callback status is 0x0005, what does it mean?
        • 3.4 Is there any example of file transfer in SDK and what is the suggested method to realize this function?
        • 3.5 Regarding the static void samples_cccd_set_cb(uint8_t conn_idx, uint16_t handle, uint16_t cccd_value) function, when connecting it will always report a cccd_value = SAMPLES_EVT_TX_ NOTIFICATION_DISABLED event when connecting. What is the meaning of this value?
    • BLE Master
      • 1. Introduction to the basic functions of BLE Master scanning
      • 2. BLE Master Scanning Application Notes
      • 3. FAQ
        • 3.1 Do I need to stop scanning when I initiate a connection?
        • 3.2 Does it support to connect to multiple devices at the same time?
        • 3.3 Does it support to set scanning power?
        • 3.4 How to use the scanning whitelist function?
        • 3.5 Can Master act as Server and Slave act as Client?
    • BLE Multi Slave
      • 1. Introduction to GR5xx Multi Slave Basic Concepts
      • 2. GR5xx Multi-slave Application Notes
      • 3. FAQ
        • 3.1 BLE slave devices originally support multiple connections, so what is the difference between multiple connections and multiple slaves? What are the specific application scenarios of dual or multiple slaves?
        • 3.2 In the actual application of dual-slave project, the broadcast of each link is independent, if there are frequent modification of the broadcast address of the application scenarios, how should it be realized?
        • 3.3 The same phone can connect to both slaves normally, but why does each slave find services that are not as expected after the connection is established?
        • 3.4 The dual slaves are connected normally, and the service discovery is normal, but when I send a message from the device to the cell phone, why can’t the cell phone receive it?
    • BLE Multi Role
      • 1. Introduction to GR5xx Multi-Master-Multi-Slave Concepts
      • 2. GR5xx Multi-Master Multi-Slave Application Notes
      • 3. FAQ
        • 3.1 What is the maximum number of connections that GR5xx can support when designing a master-slave application scenario?
        • 3.2 In ble_app_uart_multilink master-slave example, how to differentiate the slaves? How do I change the slave device settings for the default connection?
        • 3.3 Common problem analysis of open broadcast or scanning failure in BLE multi-service scenarios.
        • 3.4 In a master-multi-slave scenario, there is no problem with master-slave communication of one pair of one device, but when master-slave communication of one pair of ten devices, commands are sent to the slaves one by one via conn_idx, and the slaves can’t receive the data in case of a large amount of data, which is because of Bluetooth transmission scheduling problem?
    • BLE Multi-Connect
      • 1. GR5xx BLE Multi-connections Basic Function Introduction
      • 2. GR5xx Multi-connections Application Notes
      • 3. FAQ
        • 3.1 How many connections can the GR5xx chip communicate stably?
        • 3.2 How to optimize the stability of multiple connections?
        • 3.3 Does broadcasting need to be re-enabled after the connection is established in the “one-slave-many-hosts” scenario?
    • BLE Security
      • 1. Introduction to basic BLE SM concepts
      • 2. GR5xx BLE SM Application Notes
      • 3. FAQ
        • 3.1 There is a problem with BLE pairing, what should I do to solve it?
        • 3.2 BLE Bluetooth connection, how to connect directly without prompting pairing request?
        • 3.3 Which part of the code in the routine ble_app_hids_keyboard knows the Bluetooth pairing code? How to enter the Bluetooth pairing code? The key pairing routine?
        • 3.4 Every time the device connects, the pairing box pops up, and it is reasonable to say that only the first pairing will pop up the box, but not the subsequent ones. How to solve this problem?
        • 3.5 How to prevent GR5xx Bluetooth peripheral from being captured? How is the communication data encrypted?
        • 3.6 How to get the MAC address of the opposite device (e.g. cell phone) after pairing?
        • 3.7 After device bonding, the iOS device address will change, how to make sure the device with changed address can connect?
    • BLE Data Rates
      • 1. Theoretical Transmission Rate
      • 2. Factors affecting BLE data transfer rate
      • 3. FAQ
        • 3.1 I want to modify the PDU parameters in cell phone, but I didn’t find the API interface, how can I do it?
        • 3.2 Why is the throughput rate of Apple phone low during throughput rate test?
  • BLE Application
    • Conflict handling between BLE and XIP-Flash
      • 1. How to avoid conflicts between BLE and Flash operations
      • 2. So when is each Sector Delay needed and when is it not?
    • BLE exception code
      • 1. BLE disconnected reason introduction and analysis
      • 2. Common causes of disconnection
        • 2.1 0x98 Timeout Disconnection
        • 2.2 0xB8 Immediate Instruction Misses
        • 2.3 0xB2 Response Timeout
        • 2.4 0xCE Failure to establish connection
        • 2.5 0xA3 Remote Active Disconnection
        • 2.6 0xA6 Local active disconnection
        • 2.7 0xCD Crypto related disconnection
        • 2.8 Other Disconnects
    • BLE HID Applications
      • 1. Introduction to BLE HID
      • 2. BLE HID Application Notes
      • 3. FAQ
        • 3.1 After the HID device is successfully connected to the iOS device, the device does not respond, what is the reason?
        • 3.2 After the HID device is successfully paired with the host side, there is no response from the device side to send data, what is the reason?
        • 3.3 The product application needs to integrate multiple Keyboard and Mouse functions, how to realize it?
    • BLE Mesh
      • 1. Introduction to BLE Mesh Basic Concepts
      • 2. BLE Mesh Application Notes
      • 3. FAQ
        • 3.1 Where can I find the introduction of Mesh principle and protocol?
        • 3.2 Are BLE legacy features and BLE Mesh already included in the BLE stack library file? Or is BLE Mesh a separate protocol stack library file? Is there some documentation and information related to BLE Mesh development?
        • 3.3 How many operating modes does GR533x Mesh low power support? What is the power consumption of different operating modes?Does GR533x support specific micro-operating system?
        • 3.4 What is the maximum number of BLE nodes that can be connected to the mesh? Is there any kind of mesh topology, or is it just a star structure?
        • 3.5 Is there a Goodix Mesh SDK application development brief?
  • DFU Application
    • DFU Application Introduction
      • 1. GR5xx DFU Introduction
      • 2. DFU Program Selection
      • 3. Flash Layout Division
        • 3.1 Upgrade Mode
        • 3.2 App Bootloader Description
        • 3.3 Introduction to Important Details
        • 3.4 Third Party DFU Adaptation
      • 4. FAQ
        • 4.1 How to enable Fast DFU mode?
        • 4.2 Where is the Fast DFU rate limitation and how much rate can be reached?
        • 4.3 How is DFU low-power under RTOS?
• Tools
  • GRPLT Tool
    • 1. GRPLT basic function introduction
    • 2. GRPLT Application Notes
  • GRPLT Lite Tool
    • 1. GRPLT Lite basic function introduction
    • 2. GRPLT Lite Application Notes
  • IAR Application Notes
    • 1. Basic Introduction
    • 2. Using GR5xx SDK in IAR
      • 2.1 Generating an IAR project based on a Keil project
      • 2.2 Configuration Debugging and Downloading
  • Ellisys User Guide
    • 1. Important Note
    • 2. Preface
    • 3. About the hardware
    • 4. Getting Started
      • 4.1 Main Interface
      • 4.2 Quick Start
      • 4.3 Packet Catching Configuration
      • 4.4 Only lip packet filtering
• Hardware
  • ESD Application Notes
    • 1. GR5xx Series Chip ESD Performance Introduction
    • 2. ESD Application Notes for GR5xx Series Chipsets
  • RF Application Notes
    • 1. Introduction to GR5xx RF
    • 2. GR5xx RF Application Notes
  • Minimal System Application Notes
    • 1. Introduction to the GR5xx Minimum System
    • 2. GR5xx Minimum System Application Notes
• Application