Introduction

ALK8266WIFI, the Practically Functional, High-Throughput, Stable and reliable WIFI module Solution, Very Suitable for High-Speed and bulk data transmission in MCU System to achieve a fast, stable, reliable, and effective communication exceeding 1MBytes/s.

Here is a video demonstration how ALK8266WIFI module extends an STM32 MCU to achieve a high-speed communication, either in transmission or reception, with an effective throughput over 1MBytes/s without any packet loss: https://www.youtube.com/watch?v=6cAmyX15hYk

What is ALK8266WIFI ?

ALK8266WIFI is a high-performance WIFI module with an effective communication throughput exceeding 1 Mega-Bytes per second (Mbytes/s), verified by many mass and long-term deployments. It is a truly High-Speed WIFI module, practically functional, easy-to-integration, stable, and very suitable for MCU system with high-speed and block data transmission.

Logically it is a converter between an SPI Slave Port and TCP/UDP WIFI packets.

Why did I make it?

There are many systems based on low-end processor like MCUs which have limited resources but also expected a high-throughput, stable and reliable 802.11 wireless communication.

Traditional SDIO or USB interface wi-fi module would require a complex integration and a lot of resources, while UART wi-fi module would only afford a throughput less than 100KByes/s and less reliable.

SPI bus normally would provide a throughput faster than UART bus while requires less complex integration and CPU resources than USB and SDIO. ALK8266WIFI is such an SPI wi-fi module which provides a reliable, stable and high-speed communication via an SPI interface to the MCU but requires very limited CPU resources.

What are Application Scenarios of ALK8266WIFI?

ALK8266WIFI module is suitable for “MCU High-Speed WIFI communication”, applications such as Audio/Video WIFI tranceiving, High-Speed ADC Sampling and transmission, SD card Bulk File data tranceiving etc. Especially for those MCU platforms which have no SDIO/USB but only SPI interface, or DO NOT expect a complex integration of those interfaces, ALK8266 is a quite good choice.

What are features of ALK8266WIFI?

The solution is a result of the dedicated design with optimization covering module hardware, module firmware, and MCU host driver. The module firmware is customized from registers level other than base on Espressif standard SDK which is mainly proper form slow-speed UART applications. Therefore, it does not have those problems present in some traditional modules(e.g. frequent unexpected disconnection, communication halt, missing packets, and lack of practical functions). Mass deployment of more than 3 years tells that it is a truly high-speed, stable, flexible, and practically functional module solution:

(1) High Effective Speed, Efficient, and Short-Delay

  > Measured effective speed exceeds Mega Bytes Per seconds, capable of fast transmission bulk data such as audio, video, and some other big data.
  > Nealy-RealTime tranceiving with a gap interval less than 1ms or even 10us, in favor of some applications requiring short-delay communications.

(2) Stable with extremely Low Packet Loss (Actually no packet loss)

  > Reference testing result #1:  In an ordinary office environment with a stable transmission speed of 1MBytes/s, module could run at least 720 hours without any packet loss or errors, no halt and disconnections.
  > Reference testing result #2: In an ordinary office environment, with a stable TCP transmission speed of 1MBytes/s for more than 5 hours, then to compare the transmission side and reception side, there is no packet loss and the two sides have the same datagram.

(3) Practically Functional, Versatile and Flexible

  > Flexible and Practical Solution of Wireless Communication
    1 Supporting Multiple Access Infrastructures
       (1) 3 modes: STA-Only, AP-Only, and/or STA+AP
       (2) Communication capability without 3rd-part Access point such as routers
    2 Supporting Static IP configurations for either AP or STA
    3 Flexible and Practical Socket Capabilities
       (1) Supporting UDP, TCP Client, and TCP Server
       (2) Supporting DNS parsing and the target Socket could be in format of IP or domain
       (3) UDP Supporting Broadcasting, Multicasting, and Unicasting
    4 Supporting Multiple Link Channel and Multiple Clients
       (1) Each Link could be configured independently to be a UDP,  TCP Server, or TCP Client. 
           If configured as TCP Server, able to be connected by multiple clients simultaneously 
    5 Supporting transmission of bulk data (e.g. files) efficiently

  > Easy, Flexible and Diverse Network Access Configuration (User interface of STA Access to AP/Routers), Adapted to Various Circumstance
    1 Configured via an on-module WEB Page
      (1) No necessity of additional APP, just use ordinary browser to input directly the SSID and password with barely no prerequisite limitations.
    2 SmartConfig
      (1) Compatible with EspTouch SmartLink SmartConfig
      (2) In favor of WeChat Airkiss SmartConfig
      (3) Available with Configuration Stage Notice to increase the operational convenience and success rate.
    3 Direct Configuration
      (1) Available with SPI Interface to Input SSID and password for access, no need of UART
      (2) Compatible with UART AT commands by Espressif to input the SSID and password directly
  > Available with an On-Module Web Server to extend convenience and flexibilities of some operations
    1 Operations with normal browser, no need of APP installation
    2 Operations on Mobile, Tablet, Laptop, or PC
    3 Adaptive Portal Supported
    4 Directly Network Access Configuration, AP configuration, Socket Configuration, etc.
  > Supporting Practical and Meaningful Low Power
    1 Low Power Solution with prerequisite of adequate transmission power for adequate distance/speed
    2 Sleep with manual or automatic wake-up, low power consumption to less than 1mA in deep-sleep
    3 Capability of Power-Off and Power-Down, low power consumption less than 1uA
    4 Associated Methods to support quick wake-up, and shorten the WIFI re-connect period, which leads the WIFI Low Power Solution practical and meaningful
    5 Discussion with Customer to support Low Power from point of whole MCU system

(4) Dedicated Module Hardware Design

   > Design with Comprehensive Consideration and Technique of Signal Integrity, Power Integrity, and EMC compatibility, therefore, stable and no need of shield for a thin package with good heat release and verified by EMC certifications.
   > Factory Radio Frequency Compensation and supporting Frequency auto Calibration.
   > On-Module PCB Antenna in optimized Design, capable to transmission in 100+ meters distance without extern antenna
   > IPEX socket available for an external antenna to extern the communication distance and performance

(5) Adaptive Package in Small-size > Stamp-Style Pins with Full-hole and Half-Hole, standard 2.0-mm pitch

   > Assembly adaptive in Plug-In or SMT 
   > Very Small Dimension, Close to the smallest coin 
     - With PCB Antenna L x W = 21 x 18 mm 
     - Without PCB Antenna: L x W = 18 x 16 mm

(6) Ordinary SPI Interface to MCU Host, Easy Integration and very Limited MCU resource occupation

   > Standard SPI Slave Interface to MCU Host, adaptive to most normal MCU chip, providing a wide range of MCU solution selection.
    1 Easy interconnection, only SPI bus required for all operations of configuration, query, and tranceiving, without necessity of UART Port
    2 MCU Host Access WIFI Module in an ordinary SPI manner
      > TCI/IP Protocol Stack already integrated on-module
        1 No need of TCP/IP Protocol Stack or OS integration on MCU Anymore
        2 Therefore Easy Integration of the WIFI module to MCU system with very limited host resources requirement

(7) Available with many SPI APIs inside the Driver Library

   > MCU could call these APIs to configure, query the module and perform high-speed data transmission
   > MCU Host driver integrated with high-speed, high-efficiency, fault-tolerant, failure-correction, environment-adaptive and stable SPI access algorithm, to achieve a high-speed communication with very stable and efficient performance
     1. High-Speed and High-Efficiency Algorithm in favor of a faster tranceiving performance faster than DMA
     2. Balance Algorithm, based on analysis to the local parameters and RF environment, adaptive performing access balance and failure correction to ensure the performance and stability

(8) Compatible with Espressif Standard AT Command, and providing Anylinkin extended AT commands

  > UART Baud Rate exceeding 2Mbps

(9) Available with MCU reference Code Projects Documentations of Datasheet, Integration Reference Manual etc.

  > Verified MCU Reference Code Projects
    1 Easy integration, Debug, and Optimization
    2 Scalability Design in levels and easy for Platform

  > Lists of MCU Reference Projects (Maybe more)

Measured effective Speeds for Reference

(10) Verified by 8+ years Mass Deployment

   Many Product Models integrated with ALK8266WIFI module have been Certificated by FCC/CE/MIC etc.