Reference links:

Flutter Dart:

Flutter 3D Buttons:

https://medium.com/flutterpub/anatomy-of-material-buttons-in-flutter-first-part-40eb790979a6

Flutter Latest news:

https://medium.com/flutter/two-months-of-fluttergoodnewswednesday-a12e60bab782

Build flutter app:

https://www.youtube.com/watch?v=x0uinJvhNxIhttps://flutter.dev/docs/get-started/codelab

Flutter toggle color after click:

https://stackoverflow.com/questions/50863681/flutter-how-do-i-toggle-the-color-of-a-raisedbutton-upon-click

Flutter on codePen:

https://codepen.io/flutter

Flutter gridlist examples:

https://flutter.dev/docs/cookbook/lists/grid-lists

Fetch data from server in flutter:

https://flutter.dev/docs/cookbook/networking/background-parsing

https://medium.com/flutterdevs/parsing-complex-json-in-flutter-b7f991611d3e

UX Design in flutter:

https://uxdesign.cc/flutter-design-challenge-onboarding-concept-1f5774d55646

Get the data from API:

https://medium.com/flutter-community/parsing-complex-json-in-flutter-747c46655f51

Flutter time series:

https://stackoverflow.com/questions/51739064/flutter-json-and-time-series-charts

Flutter dart packages:

https://www.w3adda.com/dart-tutorial/dart-packages

Flutter dart introduction:

https://www.w3adda.com/dart-tutorial/dart-introduction

https://openlibrary.org/works/OL17556930W/Android_Fully_Loaded

https://archive.org/details/unlockingandroid0000able/page/n5?q=Build+android+os

Create mock server using postman:

https://learning.postman.com/docs/postman/mock-servers/setting-up-mock/

Web Socket examples:

https://www.websocket.org/echo.html

Energy consumption calculator:

https://www.rapidtables.com/calc/electric/energy-consumption-calculator.html

Git hub basic course:

https://www.udemy.com/course/git-and-github-crash-course-creating-a-repository-from-scratch/

Install svn on ubuntu:

https://linuxtechlab.com/simple-guide-to-install-svn-on-ubuntu

Flutter line chart,bar & pie chart:

https://pub.dev/packages/fl_chart

https://google.github.io/charts/flutter/example/bar_charts/simple.html

https://www.digitalocean.com/community/tutorials/flutter-bar-charts

https://github.com/imaNNeoFighT/fl_chart/blob/master/repo_files/documentations/pie_chart.md#sample-1-source-code

Flutter list & grid view link:

https://medium.com/@vignesh_prakash/flutter-listview-and-gridview-with-tabbar-221516518c75

Flutter Page color link:

https://medium.com/flutter-community/a-deep-dive-into-pageview-in-flutter-with-custom-transitions-581d9ea6dded

Flutter page control link:

https://api.flutter.dev/flutter/widgets/PageController-class.html

STM32 ABSTRACT

STM 32 MCU and MPU Roadmap contains:

1. MPU (STM32MP1):

– MPU with Arm Cortex-A7 650 MHz, Arm Cortex-M4 real-time coprocessor, TFT display, – Secure boot and Cryptography.

– Combination of audio and real time processing with cortex A and M architecture.

-STM32Cube AI tool running on cortex M4.

– Camera and audio interfaces to simplify input device integration.

Application: Used for real time and low power application and also graphic and communication high performance processing. Provide cloud based , making Smart home gateway with advance HMI and HD video.

2. High Performance MCUs(STM32F2, STM32F4, STM32FH7, STM32F7):

These MCUs are available in single core as well as dual core. A7 type having large of flash and Ram is provided.

STM32H7 having 280 Mhz embedding 2 MB flash ,1.4 MB RAM

Application: graphics applications, could connectivity, lot of security features.

Industry – Inverters, Communication gateway, Human Machine Interface

Health and Wellness- Individual assistance(hearing, Respiratory) , Measurements and Data logger.

Consumer – IOT gateway (Large Memory and rich communication peripherals), Access Control (Chrome-ART accelerator and display interfaces for TFT and MIPI-DSI), Drones(High Processing architecture with dual core option, advance timers and analog peripherals, small packages).

3. Mainstream MCUs(STM32F0,STM32G0,STM32F1,STM32F3,STM32G4):

– These are used for general purpose application having main feature as low power consumption which can take <100uA current.

– Main features is:

Efficient: Compact Cost,Best RAM/Flash Ratio, Smallest posiible package down to 8 pin,low power consumption, Accurate internal high speed clock best optimization

Robust: Low electromagnetic susceptibility, clock monitoring and 2 Watchdog, Error correct on flash, IOT ready with embedded security, Safe firmware upgrade/Install

Simple: Easy to configure with STM32CubeMx, Graphics, Easy to develop based on hardware abstraction library(HAL) or low layer library (LL).

Application:(STM32G0)

Lighting: High temperature, Advance timers, fast comparators ADC, DAC, AES and Security

Consumer Objects(Smart phones, IoT devices, Rechargeable connected devices,Drones,toys):

Low consumption in run and low power,USB type C power delivery, 64 Mhz CPU with DMA.

Smart Home(Home Appliances, Alarm and safety, Advance User Interfaces): High temp, safety monitoring feature, more RAM for flash , low consumption.

Industrial devices Motor control, Advance control(Air conditioning, E-bikes, Industrial Equipment): High temp, CANFD support, SPI,USART,I2C,Advance timers, RTC with backup register, AES and upgrade security

STM32G4: Having Se-curable memory area with configurable size, can be secured once exiting(no more access nor debug possible), Good fit to store critical data (critical routines, keys)

4. Ultra low power MCUs(STM32L0,STM32L1,STM32L5,STM32L4,STM32L4+):

STM32L0 (Cost Smart ULP champion):8/16 bit application,wide range of pin counts, 3 Product lines, Cost-effective, small packages, USB, LCD,Analog 8 to 192 kbytes of Flash, upto 20 kbytes of SRAM .

STM32L1(Broad Range Foundation): wide choice of memory sizes, 3 product lines, USB, LCD, AES rich analog EEPROM , Dual bank flash memory , 32-512 kbytes of flash up to 60 kbytes of SRAM.

STM32L4(ULP with performance) : High performance advance analog circuit, 5 product lines, 5 MSPS ADC, compare,DAC, Op-Amp,USB, OTG,LCD, AES, 64 kbytes to 1 mbyte up to 320 kbytes of SRAM.STM32L4+(ULP with More performance): Wide choice of memory size,3 product lines, 5 MSPS ADC, compare, DAC, Op-Amp,USB, OTG,LCD, AES, 1 to 2 mbyte of flash upto 640 kbytes of SRAM.

STM32L5(Advance Security): Wide choice of memory size,1 product lines, 5 MSPS ADC, compare, DAC, Op-Amp,USB type C, AES, 256 to 512 kbyte of flash upto 2560 kbytes of SRAM.

Type of Security:

Logical attack:

-malicious code injection

-Malware replacing the genuine program

-Man-in-the-middle attack

Board level attack:

-Cloning attack

-Fault injection

-Side channel attack

For such type of attack STM32L5 provided Hardware isolation, Secure key storage, Encryption, Authentication, IP protection, read out protection, active tempering, certified crypto library.

Application:

Smart peripherals ( fitnes tracker-wristband): ADC, OPAmp, DAC, SAI, SPI/UART, I2C, Display.

Smart peripherals (industrial sensors): High temp, SPI,UART, SPI/UART, I2C, TRNG and AES, FSMC, I/Os, CAN, Motor control, Display.

5. Wireless MCUs(STM32WL,STM32WB):

-Fully certified Bluetooth 5.0 radio

-2x faster speed with 2 mbps capable mode

-Extend network coverage with BLE mesh

-open Thread, zigbee 3.0

STM32WB:

Provides open 2.4 Ghz radio multi protocol, Dual core/ full cobtrol ultra power , IoT protection ready, Massive integration, cost saving, Advance RF tool, Energy control with C code generation.

Flash/RAM memory: 1 M/128 k

Application(LPWAN technology selection): Agriculture, Low value object tracking, lighting smart meter, utility maintenance, smart parking, smart building, smart grid, smart watch, High value object tracking, Connected Cars

STM32GO Architecture:

Why STM32G0 ?

1)Thinner technology,more integration & enhanced technologies.
2)Bigger flash in small packages.
3)1% internal clock.
4)1 power supply: Less external capacitors.
5)IO Maximization: smallest package eligible.

STM32G0 Subsystems::

Following are the features of STM32G0 :

1)Maximum speed upto 64Mbps
2)Flash memory interface of 1kb
3)32 timers each of 16 bit.
4)USB Power delivery.
5)Error code correction for 8 bits long for a 64-bit word.
6)12 bit ADC.
7)2 KBYTE of page granularity
8)Pre-fetch & instruction cache.(To improve performance)

Boot Pin configuration::

Boot configuration is selected as per areas given below:
1)Main flash memory
2)System memory
3)Embedded SRAM
4)Main Flash memory
5)System memory
6)Embedded SRAM.
7)Main Flash memory forced.

Note:It is possible to force booting from flash memory.

Reset Sources:

No external components are needed due to internal filter and power monitoring.System Reset sources can reset external components.

System Reset:

Resets all registers except certain RCC Registers and the RTC domain.
The reset Source flag is in the RCC_CSR register.

DMA Configuration :

1)DMA support for timers, ADC, and communication peripherals.
2)Offloads CPU from data transfer management.
3)Simple Integration.

ADC Overview :

1)12 bit ADC with 19 input channels.
2)Over-sampler.
3)2.5 Msample/sec max (12 bit resolution)
4)Interrupt generation.

Application benefits:
1)Ultra-low power consumption: 118uA @ 1 Msample/s.
2)Flexible trigger,data management to offload CPU.

System Clock :

1)Selected between HSI16,HSE,PLL,LSI and LSE.
2)System clock AHB nad APB maximum frequency:64 MHZ

RNG(Random Number Generator) overview:
1)Used when producing an unpredictable result is desirable.
2)32-bit Random number generator based on a noise source.

Application benefits:
1)Increase the randomness of numbers.
2)Strongly decrease the possibility of guessing values.

Application examples are :
Cryptography and games.

AES overview:

Transforms original text called plaintext to unreadable text called ciphertext using a secure encryption key.Supports many standard operation modes and two key sizes(128 or 256 bits).

Application benefits:
1)Protects confidentiality and /or authenticity of data.
2)Reduces cpu processing time.

Securable memory area:
The main purpose of securable memory area is to protect some part of the flash memory against undesired access.

USART

Can be configured as:
i)UART
ii)SPI master/slave
iii) Smartcard
iv)IrDA SIR
v)LIN
vi)Modbus

Application benefits:
1)Multipurpose communication peripheral.
2)Simple hardware,Only a few pins needed.
3)Wakes from low power mode.
4)Transmit and Receive FIFOs, with capability to transmit and receive in stop modes.

LPUART
Low Power Universal Asynchronous Receiver/Transmitter.Full UART communication at 9600 baud with wake up from stop modes capability when using the low speed 32.768kHz external oscillator. Higher baud rates are available with other clock sources.

Application benefits:
Inexpensive communication link between devices.
Simple hardware,only a few pins needed.
Wakes from low power STOP modes.
Transmit and receive FIFO’s ,with capability to transmit and receive in stop modes.

ART Accelerator:

Pefetch queue and branch cache principle:
Stores the first instruction and constant of branches and interrupts events.
Push them in the prefetch queue in the next time those events occur,with no execution penalty.

Chrome ART:

Provides hardware acceleration for graphical operations.

Application benefits:
Offloads CPU for graphical operations.
One pixel per cycle calculation.
Integrated pixel format converter and blender
Simple integration through graphical stack.

Batch Acquisition mode:
Only the needed communication peripheral + 1DMA +1 SRAM are configured with clock enables in sleep mode.
Flash memory is put in power down mode and flash clock is gated off during sleep mode.
Enter either sleep or Low-power sleep mode.

STM32 Cube IDE:

(Integrated Development Platform for STM32 Embedded Solutions)

STMicroelectronics is a semiconductor provider

• STM32 is μC & μP general purpose brand

• Arm© 32b CPU(s) based

• Part of worldwide top 3 μC vendors

• More than x32 μC unit sold per second

• STM32 devices are augmenting our daily life

• Kitchen appliances, power plugs, audio headsets,white appliances, car facilities, energy smart grid, E-city facilities, E-toys, E-cigarettes, E-bicycles, E-watches, …

Elevator

An elevator is a platform that is used for lifting people up and down in the buildings. Elevators are part of almost all commercial and residential buildings.It is a vertical transport vehicle that efficiently moves people or goods between floor of a building. Elevators are generally power by electric motors that drive traction cables and counter weight with the help of motors.The overall control is done by control system.
Key parts of elevator are:
.One or more cars(metal boxes) that raise up and down.
.Counter weight that balance the car.
.An electric motor that hoist the car up and down,including a braking system.
.A system of strong metal cable and pulley running between the car and the motor.
.various softer system to protect the passengers if cable breaks.
In large building an electronic control system that direct the car to the correct floor using a “elevator algorithm” to ensure large number of people are moved up and down in the quickest, most efficient way. Intelligent system are programmed to carry many more people to the required floor.

Types of Elevator:There are variety of different hoist mechanism are used to lift up an lower elevator cabs. The most familiar type of elevators are discussed below

  • Hydraulics Elevator : It is typically used in low-rise application and its components are fluid tank, buffer and piston.
  • Traction Elevator: It uses rope that pass over a wheel attached to a motor that sets above the elevator shaft. This elevators are used for mid to high rise application due to their increased speed and maximum traveling heights.
  • Passenger Elevator : Passenger elevators is meant to carry people to their desired floor. They are by for the most prominent types of elevator and are electric elevators mainly based of electric motors and control systems.

Parts of Elevator and its functions : Elevator is made by assembling various parts some are visible to the user and some are working in background. Lets take a close look at parts of elevator and its functions.

  • Car : cabin is the main part of elevator which is designed for the shipment of people, goods and services. It contain user interface system that is display board and the switches through which user interact with the system.
  • Speed Governors : The speed regulating system of elevator is known as speed governor. If the elevator runs more than the speed limit ,the speed governor control the speed .It is usually attached to the bottom of the car and is also known as governor rope.
  • Electric motor : It is main element of which the movement of the car is managed, in case elevator faces and serious condition then electric motor help in preventing it and provide smooth functioning of lift.
  • Elevator rail : Sliding up and down in the elevator is possible with the proper functioning of the rail.
  • Elevator shaft : Car cabin moves in this space depending upon the type of elevator ,the location of the shaft can be varied.
  • Doors : Elevator door are meant for entry and exit , it might be manually operated door or automatic operated door.
  • Drive Unit : Everything that works under electricity must have a motor attached for the functioning , it contain a motor that drive a lift.
  • Display : Electronic display are inside of the car as well as on the outside of the car. It display the current status of the car , switches are implemented on the board to provide instruction to the elevator and to interact with the control system of the elevator.
  • Safety Devices : Mechanical devices are attached to the elevator for safety reasons. In case elevator travel downward with a max speed limit, safety device can maintain a safety and secure traveling.

Working Principle : Elevator work on law of conservation of energy. The elevator gives you potential energy when we are going up and it takes energy from us when we are coming down.

The user call the elevator on the required floor by just pressing the switch then elevator receives request and start moving on the requested floor. Appropriate floor control system gets sensor information and control system signals elevator to stop. Elevator stops control system and signals door to open as soon as door opens the people enter in the car .control system signals the door to close and elevator car door closes , user provide input to the control system on which floor they want to go control system receives the request and motor of the elevator start turning and elevator start moving. As soon as the request floor is reached control system gets sensor information and control system signals elevator to stop and control system signals the door to open and the process repeat continue. If there is no request form the user then then the car will be in the idel state and wait for the call from the user.

Power Supply: Power supply of elevator is s complex process and that is regulated by several laws and it must be provided energy from two independent power source. Break the power is permitted only its time of auto recovery, urgent task is to ensure the possibility of lifting equipment work after the termination of main power supply. As soon as the main power supply is lost then UPS (uninterrupted power supply) will provide the immediate and uninterrupted power supply until inverter or generator provides power supply. This will provide the continuous functioning of elevator without any interruption with the help of power backup.


Control System of Elevator: Group control is the brain of elevator control system which decides were the car should go and stop. There can be several group controller in an elevator. One of the group control is the master that deliver the hall calls to the elevator, and other group control are backup. Other functions inside the car e.g. register and canceling of car call , door control and measurement of car loads are handled by the elevator control .

Intelligent elevator components communicate with each other through serial transmission using controller area network (CAN). Typical control software for an elevator include an operating system , task scheduling programs , input ,output and communication program and program for controlling and optimizing the function of the components.

Standby Mode of Elevator: Standby solution power down the elevator equipment when it is not in use, providing substantial energy saving, especially in buildings with period of lower elevator usage. I-cab sensors and software automatically switch to a “sleep mode’ turning of lights, fans, music and display when the car is not in use. The 25% to 80% of the overall energy consumption of the elevator can be saved depending on multiple variable including the employed control system, lightning type, floor display and operating console in each floor and inside the elevator cabin. As soon as the call button is pressed by the user the elevator will wake up from the sleep mode and again start functioning as earlier and if it is again not used for some time then again it will in standby mode.
Elevator can be made energy efficient by using LED cab lights within an elevator car and their adjustment to movement detector are one of the main contributor toward efficient power consumption in a building. LED also emit less heat, resulting less energy needed to maintain the temperature in cab. LED lightning is currently utilized in many new elevators.

Regenerative Drives of Elevator: When brakes are applied the energy is released from the electric motors in the form of heat. regenerative drives has the ability to recycle energy rather than wasting it as heat. They work by capturing and converting the energy from braking to maintain the elevator speed. Traction elevator uses a counterweight to balance the weight of elevator car and passenger. If counter weight is to heavy or to light it then the elevator will overwork the motor and the braking system. When the elevator is traveling up the car are light or traveling down car are heavy. The elevator applies the brake to maintain their rated speed. Braking is provided by allowing the AC motor to operates as generator , converting mechanical energy to electrical energy which is dispatched as heat by special heat resistor . The regenerative drive captures the energy and channel it back to the building or the city power grid.