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Build electronic scale with Smart LCD Module

Build electronic scale with Smart LCD Module
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Build electronic scale with Smart LCD Module - 1

Application Note Title: Incorporating HMT050ATA-2C as a Digital Scale Display 1. Background The system we are going to build includes a data acquisition circuit with a host MCU and a HMT050ATA-2C smart LCD module as scale's display. HMT050ATA-2C is a smart LCD module with following specifications: ⚫ ⚫ ⚫ ⚫ ⚫ ⚫ 5 inch TFT Color LCD with 800 (RGB) x 480 pixels with 16 bits color per pixel and LED backlight High-resolution resistive touch panel for user inputs and interactions 32 bits ARM Micro-Controller with a Smart LCD Engine to process graphics, commands from host A large flash memory to hold graphical data and configuration information locally A RS232 or a Logic-Level Serial Interface, connect the module to any host MCU or any other device supporting serial communication A USB interface to configure the module The HMT050ATA-2C provides a very easy and fast way to create high-end embedded applications for Industrial Controls, Instruments, and Medical devices. The TFT LCD module shows user interface, which can be created with Topway's UI development tool. A host MCU may connect to the module, control it and receive input events. Information showed is for guidance only; never use as a reference design. TOPWAY will not responsible for any damage or loss on using the provided information. Please evaluate before using.

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Build electronic scale with Smart LCD Module - 2

Application Note 2. Content 2.1 System Overview A Digital scale is a very good example explaining the functionality and the way of developing applications with HMT050ATA-2C. The proposed Digital Scale shall include: • Two Load Cells • ADC Board (e.g. based on AD7190) with SPI • Host MCU Board (e.g. based on a small ARM Cortex M0, PIC or AVR) with SPI and UART • Smart LCD Module HMT050ATA-2C with UART • Power Supply The ADC Board is providing following functionality: • Converting the bridge voltages of two load cell channels • A ratio-metric measurement circuit is recommended The Host MCU is...

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Build electronic scale with Smart LCD Module - 3

Application Note SHENZHEN T Of WAY TECHNOLOGY CO.. LTD.| | 2.2 The HMT050ATA-2C Smart LCD Module Smart LCD module has the following parts and functions: • Contents and functionalities are organized in one (or more) page(s) • Page is a visual display on screen, contains: o Images o Icons o Variables (VP) o Animations o Time and Date using internal Real Time Clock • Page can hold multiple touch sensitive areas, which may trigger events like: o Transition to another page o Showing specific icons o Setting variable value or performing calculation o Sending touch event via serial interface o...

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Build electronic scale with Smart LCD Module - 4

Application Note 2.3 The Types of Operation and Functions of a Digital Scale The Host Microcontroller (MCU) is the heart of proposed system. This document does not go into detail on how to implement operational types inside the Host MCU. However, it shall give an overview about all necessary operational types to implement a Digital Scale and how the Host Controller and HMT050ATA-2C may communicate. Depends on the operational Type, the HMT050ATA-2C displays different contents and Touch Events may trigger certain processing or change in Type. Types of Operation and Functions are: Off Type...

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Build electronic scale with Smart LCD Module - 5

Application Note 2.4 A design proposal of a SPI Data Acquisition Board The Data Acquisition Board may be based on any suitable ADC with SPI or any other suitable interface. Ratio-metric measurement is preferred. Following is a proposed circuit for reference. The circuit is based on the two-channel precision ADC AD7190. It can be connected to via SPI. 2.5 Recommendation on Host MCU Between the ADC and HMT050ATA-2C is a host MCU. This MCU can be any 4, 8-bit or even 32-bit ARM based. It should provide hardware SPI and UART or software emulated SPI and UART. It does not require lots of...

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Build electronic scale with Smart LCD Module - 6

SHENZHEN TO#»WAY TECHNOLOGY CO.. LTD. 2.6 Step by step description for creating a Digital Scale’s Graphical User Interface with Topway’s UI Editor and how to upload design project to the HMT050ATA-2C As mentioned earlier, the HMT050ATA-2C will present the Types of Operation with pages. We need to design these pages. Topway’s RG Tools is the tool we use. A page on Smart LCD Module is a collection of graphical and touch related elements such as: • Background Images • Icons • Text and Numerical Outputs • Animations • Graphs • Touch Areas A page usually represents an operation screen. Besides...

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Build electronic scale with Smart LCD Module - 7

SHENZHEN TO#»WAY TECHNOLOGY CO.. LTD. In this project we will use following items: • Pages • Background Images • Icons • String Variables • 32-bit signed integer Editor’s top icon bar contains varieties of objects. For this project, we will use following features: F TOPWAY RGTools - [PGOOOO] Select an Object Insert Touch Area Insert VP String Area Insert numerical VP Area Compile & Download to Module After the creation of the project we will define which images and icons we want to use, also we will need to define the variables we need. [-: |8S| Background Images E3 DP0000-bkg4 0 Icons...

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Build electronic scale with Smart LCD Module - 8

SHENZHEN TO#»WAY TECHNOLOGY CO.. LTD. 2.) Next step is importing of icons. We will import just one icon. This icon (keys2.jpg) holds three keys we will need to operate our Digital Scale. The keys are Mode, On/Off and Tare ani Our new icon becomes listed under Icons + ISJ Pages syyj Animations Gp- @ Variables(VP) i EO USB Access Lock 3.) Several different variables (VP) are needed. We create following variables: • String Variable Unit_String • 32-bit Number Variable Channel1 • 32-bit Number Variable Event Flags • 32-bit Number Variable Unit • 32-bit Number Variable Page_ID anl |§H Pages |S|1...

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Build electronic scale with Smart LCD Module - 9

SHENZHEN TO#»WAY TECHNOLOGY CO.. LTD. After creating and renaming all variables we should be able to see the following list of variables: The variables have following usage: • Unit_String: Contains a string of weight unit shown on LCD, which may be "g” or "oz” • Channel1: Includes the Weight of Channel 1 (in 0.1g or 0.1 oz steps) shown on the left side of the LCD • Channel2: Includes the Weight of Channel 2 (in 0.1g or 0.1 oz steps) shown on the left side of the LCD • Event Flags: Includes Flags representing which Button was pressed. Bit0 = 1 => Tare was pressed, Bit1 = 1 => Mode was...

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