SLAA654A November   2014  – July 2015 CC430F6147 , MSP430F412 , MSP430F413 , MSP430F4132 , MSP430F415 , MSP430F4152 , MSP430F417 , MSP430F423A , MSP430F4250 , MSP430F425A , MSP430F4260 , MSP430F4270 , MSP430F427A , MSP430F435 , MSP430F4351 , MSP430F436 , MSP430F4361 , MSP430F437 , MSP430F4371 , MSP430F438 , MSP430F439 , MSP430F447 , MSP430F448 , MSP430F4481 , MSP430F449 , MSP430F4491 , MSP430F4616 , MSP430F46161 , MSP430F4617 , MSP430F46171 , MSP430F4618 , MSP430F46181 , MSP430F4619 , MSP430F46191 , MSP430F47126 , MSP430F47127 , MSP430F47163 , MSP430F47166 , MSP430F47167 , MSP430F47173 , MSP430F47176 , MSP430F47177 , MSP430F47183 , MSP430F47186 , MSP430F47187 , MSP430F47193 , MSP430F47196 , MSP430F47197 , MSP430F477 , MSP430F478 , MSP430F4783 , MSP430F4784 , MSP430F479 , MSP430F4793 , MSP430F4794 , MSP430F6433 , MSP430F6435 , MSP430F6436 , MSP430F6438 , MSP430F6458 , MSP430F6459 , MSP430F6630 , MSP430F6631 , MSP430F6632 , MSP430F6633 , MSP430F6634 , MSP430F6635 , MSP430F6636 , MSP430F6637 , MSP430F6638 , MSP430F6658 , MSP430F6659 , MSP430F6720 , MSP430F6720A , MSP430F6721 , MSP430F6721A , MSP430F6723 , MSP430F6723A , MSP430F6724 , MSP430F6724A , MSP430F6725 , MSP430F6725A , MSP430F6726 , MSP430F6726A , MSP430F6730 , MSP430F6730A , MSP430F6731 , MSP430F6731A , MSP430F6733 , MSP430F6733A , MSP430F6734 , MSP430F6734A , MSP430F6735 , MSP430F6735A , MSP430F6736 , MSP430F6736A , MSP430F6745 , MSP430F67451 , MSP430F67451A , MSP430F6745A , MSP430F6746 , MSP430F67461 , MSP430F67461A , MSP430F6746A , MSP430F6747 , MSP430F67471 , MSP430F67471A , MSP430F6747A , MSP430F6748 , MSP430F67481 , MSP430F67481A , MSP430F6748A , MSP430F6749 , MSP430F67491 , MSP430F67491A , MSP430F6749A , MSP430F67621 , MSP430F67621A , MSP430F67641 , MSP430F67641A , MSP430F6765 , MSP430F67651 , MSP430F67651A , MSP430F6765A , MSP430F6766 , MSP430F67661 , MSP430F67661A , MSP430F6766A , MSP430F6767 , MSP430F67671 , MSP430F67671A , MSP430F6767A , MSP430F6768 , MSP430F67681 , MSP430F67681A , MSP430F6768A , MSP430F6769 , MSP430F67691 , MSP430F67691A , MSP430F6769A , MSP430F6775 , MSP430F67751 , MSP430F67751A , MSP430F6775A , MSP430F6776 , MSP430F67761 , MSP430F67761A , MSP430F6776A , MSP430F6777 , MSP430F67771 , MSP430F67771A , MSP430F6777A , MSP430F6778 , MSP430F67781 , MSP430F67781A , MSP430F6778A , MSP430F6779 , MSP430F67791 , MSP430F67791A , MSP430F6779A , MSP430FE423 , MSP430FE4232 , MSP430FE423A , MSP430FE4242 , MSP430FE425 , MSP430FE4252 , MSP430FE425A , MSP430FE427 , MSP430FE4272 , MSP430FE427A , MSP430FG4250 , MSP430FG4260 , MSP430FG4270 , MSP430FG437 , MSP430FG438 , MSP430FG439 , MSP430FG4616 , MSP430FG4617 , MSP430FG4618 , MSP430FG4619 , MSP430FG477 , MSP430FG478 , MSP430FG479 , MSP430FG6425 , MSP430FG6426 , MSP430FG6625 , MSP430FG6626 , MSP430FR4131 , MSP430FR4132 , MSP430FR4133 , MSP430FR5870 , MSP430FR5872 , MSP430FR58721 , MSP430FR5922 , MSP430FR59221 , MSP430FR5970 , MSP430FR5972 , MSP430FR59721 , MSP430FR6820 , MSP430FR6822 , MSP430FR68221 , MSP430FR6870 , MSP430FR6872 , MSP430FR68721 , MSP430FR6877 , MSP430FR6879 , MSP430FR68791 , MSP430FR6887 , MSP430FR6888 , MSP430FR6889 , MSP430FR68891 , MSP430FR6920 , MSP430FR6922 , MSP430FR69221 , MSP430FR6927 , MSP430FR69271 , MSP430FR6928 , MSP430FR6970 , MSP430FR6972 , MSP430FR69721 , MSP430FR6977 , MSP430FR6979 , MSP430FR69791 , MSP430FR6987 , MSP430FR6988 , MSP430FR6989 , MSP430FR69891 , MSP430FW423 , MSP430FW425 , MSP430FW427 , MSP430FW428 , MSP430FW429

 

  1.   Designing With MSP430™ MCUs and Segment LCDs
    1.     Trademarks
    2. 1 Introduction: MSP430 + LCD End Applications
    3. 2 MSP430 LCD Portfolio
    4. 3 Segmented LCD Operation
      1. 3.1 LCD Structure (Simplified)
      2. 3.2 LCD Drive Basics
    5. 4 MSP430 LCD Features
      1. 4.1  Muxing
        1. 4.1.1 Muxing Example
      2. 4.2  Charge Pump
      3. 4.3  Biasing
      4. 4.4  Contrast Control
      5. 4.5  Timing
      6. 4.6  Memory Map
      7. 4.7  Blinking
      8. 4.8  LCD Output Pins
      9. 4.9  Ultra-Low-Power Features
      10. 4.10 Driving Large LCDs
    6. 5 LCD Layout and Software Considerations
      1. 5.1 LCD Layout Tips
        1. 5.1.1 Hardware-Driven Layout
        2. 5.1.2 Software-Driven Layout
        3. 5.1.3 General Layout Rules
      2. 5.2 LCD Software Tips
        1. 5.2.1 Create a Lookup Table
        2. 5.2.2 Use of #defines
        3. 5.2.3 Efficient Clearing of the LCD Memory
        4. 5.2.4 Double-Buffering of the Display Buffer Using Dual Display Memory
        5. 5.2.5 Efficient Binary-to-BCD Conversion
    7. 6 Devices Without LCD Module
      1. 6.1 Bit-Banged LCD
        1. 6.1.1 Bit-Banged LCD Tradeoffs
      2. 6.2 Displays With Built-in Drivers and Serial Interface
    8. 7 Additional Resources
  2.   Revision History

5.1 LCD Layout Tips

Depending on the muxing used, it may take multiple Sx pins to display an entire digit or character on the screen. Which display areas are muxed together depends on the particular LCD glass used and how it has mapped these segments to drive pins. Choosing the right LCD display can make software easier. For example, if a display has the Sx pins mapped to segments that allow it to display any numerical digit using only one or two Sx pins, that can make the code easier to write. The mapping of pins to LCD segments is found in the LCD data sheet.

Figure 13 shows some information from the data sheet for the LCD glass on the MSP-EXP430FR4133 Launchpad Development Kit, which has a 4-mux display. This display allows for showing alphanumeric characters in addition to simple digits. Looking at the pin mapping found in the display data sheet, you can see that the segments required to display any digit 0-9 take only two Sx pins – pin 1 and 2 of the LCD. To display any alphabet character, 4 segment pins are used.

fig13_4mux_display_example.gifFigure 13. 4-Mux Display Data Sheet Example

In addition to the mapping of the LCD glass itself, careful selection of which Sx segment pins on the MSP430 to connect to which LCD segment pins on the LCD glass can also have a big impact on both layout and software.