Juvtmall

2. Arduino learning notebook -- What is Arduino? (VOL. 1)         Juvtmall (a company supply PCB Prototyping, PCBA service, sell module and so on)   If you want to understand arduino, it’s needed to know what a single chip machine is. Because the arduino platform is based on single chip of the AVR instruction set. 1. What is a MCU? What are the differences between MCU and COMPUTER? A computer includes five parts: CPU(operation 、 control) 、 RAM(digital storage) 、 ROM （ program storage ）、 I/O (serial, parallel output, etc.). These parts are divided into a number of chips on a personal computer(PC), which are united on a printed circuit board(PCB) called mainboard. In SCM, these parts are all united in a piece of integrated   circuit chip, so MCU. There are kinds of single chip machines, beside the above parts, also integrates other parts such as analog/digital conversion (A/D) and digital/analog conversion (D/A), etc. 2、 Wh...

1. Arduino learning notebook -- Button experience (vol.2)               www.juvtamll.com    ( a company supply PCB Prototyping, PCBA service, sell modules.) The standard is 512 means 2.5V in this experience, someone get trouble in this way: led will light when the button haven’t been pushed sometimes. This is caused by the interference, such as the induced voltage is more than 2.5V, for improving the accuracy, we need to improve the threshold. The reason of closing to the button with hand will light the lED is that there’s no pull-down resistance, then it has been interference by the outside. The way of set the Pull-down resistance: The following is using a Arduino Uno’s build-in LED as the indicated LED This program is different from the vol.1, for this program has been added a software for eliminating noise, the purpose is for achieve the goal of push button then the LED light, or when you push the butt...

1. Arduino learning notebook -- Button experience               www.juvtamll.com   ( a company supply PCB Prototyping, PCBA service, sell modules.) The button is a commonly used key, normally used to connect or disconnect the circuit, so as to control the the motor or other equipment. The buttons have a variety of appearance. This experiment is used for this kind of miniature keypad, 6mm, as shown below. Look at the back of the button, it has 4 pins. When the button not be pushed, No. 1 and 2 are connected, 3 and 4 are connected. When the button is pressed down, all the pins will be connected. We use button to control the led. The general situation is install the button series in the led circuit, however, it’s too simple. We use the indirect way, the button judge output voltage from the circuit. If the voltage is greater than 4.88 V, output high level to the LED circuit, whereas output low level. ...

Juvtmall ( a company supply PCB Prototyping , PCBA service and kinds of sensors, modules ) It is said that there is a kind of cat that can reach the heaven to become the god as long as nine tails. Every practice to one stage will have one more tail, but it is very difficult to success. When the cat uniting to eight tails, it will get a prompt to help its owner to achieve a wish, after the completion of wish, it will grow a new tail as well as fall off a tail. It is still eight tails. It seems like a strange cycle, that is to say it's impossible to build a nine tail anyway. A very devout cat, has been practicing for hundreds of years and helping many people realize the desire, but still eight tails. One day, it met a boy be trapped by wolves, by its nature, quickly drove the wolves and saved the boy, then found the youth is the first master's offspring. According to the rules, it needs to help the boy realize a wish. The cat asked the boy what his wish was, and he coul...

As always, in order to try a new method I must decide on a new project which will encourage me to deal the new method with enthusiasm. The project I decided to build was a new code for the  Water heater project  posted here a while ago. Reviewing the old post, I found its code more or less a "proof-of-concept" code, where the emphasis was on the hardware. The project description in a few bullets: The ESP8266 connects to my router via WiFi and serve as a web-client. A website consists of a manageable SQL database with the schedule of the water heater with a main page for the user. The user can add/erase queries from the database. Every 5 minutes the ESP8266 sends a GET request to the the website and receive the minutes left to turn ON/OFF the water heater. That way, even if the WiFi fails at some point the ESP8266 will still have the most updated schedule from the website. While sending the GET request, the website saves data of the time of request, the status of the G...

Introduction The ESP-32s module combines the function of Wi-Fi and Bluetooth, the Wi-Fi fits for Wi-Fi 802.11/b/g/n/e/I, the Bluetooth fit for V4.2 BR/EDR and BLE standard. ESP-32s not only provides RTOS(real time operate systems), integrate abundant analog sensing, digital interfaces, but also integrates the antenna switch, radio frequency, power amplifier, low noise amplifier, filter and power management module. It don’t need to connect controller for it has the MCU.Compared to the last vision of ESP8266, the ESP-32s supply more internal storage and more I/O for developing, and the SP-32s could transform the video data directly. Features Two 32-LX6 CPUs Wi-Fi 802..11/b/g/n/e/l 802.11 n(2.4 GHz) , with speed up to 150 Mbps V4.2 BR/EDR Fit for BLE standard Maximal frequency: 250MHz Operate temperature: -40 to +125℃ (fit for the industrial environment) Self-calibration Low power mode and kinds of sleepy mode for different application Appl...