Abstract: This article is based on Alibaba Cloud's official help document, the purpose is to let everyone understand the HaaS development board hardware resources.
table of Contents
2. Several hardware resources that need special instructions
2.5 Details of the power supply
3. About the main control chip HaaS1000
Basic steps for beginners to get started with Alibaba Cloud Haas100 development board
1. Introduction to hardware
The picture below is the HaaS100 development board released by Alibaba Cloud at the 2020 Yunqi Conference (HaaS600 will also be released soon). As can be seen from the figure, the development board is very well made and is very suitable for the development of Internet of Things projects. The power supply and interface of the industrial standard, anti-surge and reverse connection protection, stable work for 24 hours and the design of installation screw holes are all It is to meet "rapid development" and rapid delivery requirements. The board size is not too big or small, just install it directly into the project cabinet (cabinet) to reach the delivery conditions.
The back of the development board is shown in the figure below.
Based on the above interface and hardware analysis, the basic functional framework of the hardware can be preliminarily sorted out.
According to the official document "HaaS Hardware Specifications" , the hardware interfaces are as follows, and their performance indicators are shown in the figure below.
2. Several hardware resources that need special instructions
2.1 Button
There are two buttons on the HaaS100, one long and one short, the short is the reset button, and the long is the custom button. Can be used for operations such as network distribution.
Looking at the subsequent circuit components of the button, the reset button should use an RC circuit. The principle is shown in the figure below. After measurement, the reset button pin can control the reset signal voltage to change from 2.9V to 0V.
The custom buttons are more interesting. It seems that there will be resistance containers and diodes, but in fact, the level connected to the main control chip should not be processed.
The voltage is in a floating state, and if the button is pressed, it becomes 0V. The control method of the button should be as shown in the figure below (the text in the picture is only for explaining the principle)
2.2 TF card slot
Judging from the degree of indirection of the follow-up circuit of the card slot, the main control chip should contain SDIO functions, which has consistently continued the powerful functions of the Cortex series of chips.
2.3 Indicator
There are 6 power indicator lights. The indicator light in the upper right corner is the power source, and the other 5 are GPIO indicator lights.
The corresponding port number is found in Ali’s documentation
2.4 Ethernet interface
Support 10/100M rate. What is used is FC1101 chip, this chip is called network transformer.
What is a network transformer?
What is the purpose of the network transformer.
2.5 Details of the power supply
The stability and reliability of the power supply circuit are important parameters of the development board. If you dare to design the power supply part on the board, you must have a strong strength.
This board is very well done. Look at two details:
First of all, a common mode choke (Common mode Choke) is used, which is often used in computer switching power supplies to filter common mode electromagnetic interference signals. In the board design, the common mode inductor also plays the role of EMI filtering, used to suppress the electromagnetic wave generated by the high-speed signal line to radiate outward. This is the one in the picture below.
An anti-reverse circuit is also designed, which may be realized by a MOS tube. The anti-reverse connection function is the standard configuration of high-end development boards.
The simplest anti-reverse circuit is the principle shown below.
3. About the main control chip HaaS1000
The model of the development board is HaaS100, and the main control chip is HaaS1000.
To have a deeper understanding of hardware functions, look forward to the announcement of the master chip manual in the near future.
For the introduction of building and compiling helloworld routines in the HaaS100 development board environment, please refer to the previous article
Basic steps for beginners to get started with Alibaba Cloud Haas100 development board