Fujitsu Microelectronics (Shanghai) Co., Ltd. Application Note

MCU-AN- 500063-E-10

F²MC-8FX FAMILY 8-BIT MICROCONTROLLER

MB95310/370 SERIES

LCD Hardware Design API

APPLICATION NOTE

LCD Hardware Design API V1.0 Revision History

MCU-AN- 500063-E-10 – Page 2

Revision History

Date Author Change of Records

2009-11-10 Jane Li V1.0, First draft

This manual contains 14 pages.

© 2009 Fujitsu Microelectronics (Shanghai) Co., Ltd

1. The products described in this manual and the specifications thereof may be changed without prior notice. To obtain up-to-date information and/or specifications, contact your Fujitsu sales representative or Fujitsu authorized dealer.

2. Fujitsu will not be liable for infringement of copyright, industrial property right, or other rights of a third party caused by the use of information or drawings described in this manual.

3. The contents of this manual may not be transferred or copied without the express permission of Fujitsu.

4. The products contained in this manual are not intended for use with equipments which require extremely high reliability such as aerospace equipments, undersea repeaters, nuclear control systems or medical equipments for life support.

5. Some of the products described in this manual may be strategic materials (or special technology) as defined by the Foreign Exchange and Foreign Trade Control Law. In such cases, the products or portions thereof must not be exported without permission as defined under the law.

LCD Hardware Design API V1.0 Contents

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Contents

REVISION HISTORY............................................................................................................ 2

CONTENTS .......................................................................................................................... 3

1 INTRODUCTION.............................................................................................................. 4

2 BACKGROUND ............................................................................................................... 5

3 DESCRIPTION OF LCD PROTOCOL.............................................................................. 6

3.1 LED On condition .................................................................................................... 7

3.2 LED Off condition .................................................................................................... 7

3.3 LCD Code ............................................................................................................... 8

3.4 LCD RAM................................................................................................................ 9

4 LCD HARDWARE DESIGN ........................................................................................... 10

4.1 Hardware Design................................................................................................... 10

5 USAGE DEMO............................................................................................................... 12

6 ADDITIONAL INFORMATION ....................................................................................... 13

7 APPENDIX..................................................................................................................... 14

7.1 Figures .................................................................................................................. 14

LCD Hardware Design API V1.0 Chapter 1 Introduction

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1 Introduction

This document introduces API for LCD hardware design.

MCU LCD module drives LCD panel by connect SEG and COM to LCD panel. In following chapters we will describe the LCD module hardware design and protocol.

LCD Hardware Design API V1.0 Chapter 2 Background

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2 Background

This chapter introduces background of LCD.

Liquid Crystal Display (LCD) is drove by COM and SEG, and be lighted on by voltage bias between COM and SEG.

There are two LCD driving voltage split resistor. They are internal split resistor and external split resistor. And bias can be selected between 1/2 bias and 1/3 bias.

How many COM used will decide the duty number. When 4 COM used the duty is 1/4.

LCD used normally with internal LED cell, figure 2 – 1 describes the LED define and LCD work theory.

Figure 2 - 1 LCD work theory

LCD Hardware Design API V1.0 Chapter 3 Description of LCD Protocol

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3 Description of LCD Protocol

This chapter describes protocol of LCD module.

Those liquid crystal elements are turned "ON" for display which has the maximum potential difference between the common and segment outputs. Figure 3 – 1 simply describes LCD drive protocol.

Figure 3 - 1 1/4 Duty 1/3 Bias Output Waveform Example

LCD Hardware Design API V1.0 Chapter 3 Description of LCD Protocol

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3.1 LED On condition

When the VCOM is V3(highest voltage) and the VSEG is V0(lowest voltage), the potential is the highest voltage V3. So the LED will be lighted on.

Figure 3 - 2 LED On Wave

3.2 LED Off condition

When the VCOM is V3(highest voltage) and the VSEG is V1(lower voltage), the potential is the lower voltage V2. So the LED will be lighted off.

Figure 3 - 3 LED Off Wave

LCD Hardware Design API V1.0 Chapter 3 Description of LCD Protocol

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3.3 LCD Code

Writing data to LCD RAM will set potential to COM and SEG. When the potential is highest the correlative LED will lighted on, or the correlative LED will off.

Figure 3 – 2 describes the potential between COM and SEG.

Figure 3 - 4 LCD Code

LCD Hardware Design API V1.0 Chapter 3 Description of LCD Protocol

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3.4 LCD RAM

LCD RAM is used to save data write to COM and SEG. If user wants to display different number it only writes different data to LCD RAM. Following figure describes how to define LCD RAM.

Figure 3 – 5 describes the LCD RAM data when in 8-seg LED

Figure 3 - 5 LCD RAM 8_seg Hex

Figure 3 – 6 describes the LCD RAM data when in 16-seg LED

Figure 3 - 6 LCD RAM 16_seg Hex

LCD Hardware Design API V1.0 Chapter 4 LCD Hardware Design

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4 LCD Hardware Design

This chapter describes hardware design of LCD module.

4.1 Hardware Design

For LCD hardware design, user only needs to connect MCU COM to LCD panel COM and connect MCU SEG to LCD panel SEG. If user want to use external voltage user must supply V0~V3 voltage outside the MCU.

Figure 4 - 1 is a sample hardware design for COM and SEG.

Figure 4 - 1 LCD Hardware Design

LCD Hardware Design API V1.0 Chapter 4 LCD Hardware Design

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Figure 4 – 2 is a sample hardware design for V0~V3.

Figure 4 - 2 LCD Drive Power

LCD Hardware Design API V1.0 Chapter 5 Usage Demo

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5 Usage Demo

This chapter describes how to debug the sample code on EV-Board and what will happen when the code is running.

There is a simple project LCD.prj to debug. This project is based on our EV-Board MB2146-450-E and the target MCU is MB95F310.

Figure 5 – 1 is debugging example

Figure 5 - 1 Debugging Example

LCD Hardware Design API V1.0 Chapter 6 Additional Information

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6 Additional Information

For more information about how to use MB95310 EV-board, BGM Adaptor and SOFTUNE, please refer to EV-Board MB2146-450-E User Manual, or visit

Web: http://www.fujitsu.com/cn/fmc/services/mcu/

LCD Hardware Design API V1.0 Chapter 7 Appendix

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7 Appendix

7.1 Figures

Figure 3 - 1 1/4 Duty 1/3 Bias Output Waveform Example ..................................................... 6

Figure 3 - 2 LED On Wave..................................................................................................... 7

Figure 3 - 3 LED Off Wave..................................................................................................... 7

Figure 3 - 4 LCD Code........................................................................................................... 8

Figure 3 - 5 LCD RAM 8_seg Hex......................................................................................... 9

Figure 3 - 6 LCD RAM 16_seg Hex........................................................................................ 9

Figure 4 - 1 LCD Hardware Design ...................................................................................... 10

Figure 4 - 2 LCD Drive Power .............................................................................................. 11

Figure 5 - 1 Debugging Example.......................................................................................... 12