Difference between revisions of "STM32 I²C LCD"

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[[Category:C]][[Category:STM32 Development]][[Category:STM32 HAL]][[Category:STM32CubeMX]][[Category:STM32CubeIde]][[Category:Embedded]][[Category:STM32]][[Category:I²C]][[Category:Work in progress]]{{metadesc|Using I2C GPIO expander to drive 16x2 or 20x4 LCD displays}}
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[[Category:C]][[Category:STM32 Development]][[Category:STM32 HAL]][[Category:STM32CubeMX]][[Category:STM32CubeIde]][[Category:Embedded]][[Category:STM32]][[Category:I²C]][[Category:Work in progress]]{{metadesc|Using I²C GPIO expander to drive 16x2 or 20x4 LCD displays}}
 
[[File:16x2-LCD-Module.jpg|400px|thumb|16x2 LCD Module]]
 
[[File:16x2-LCD-Module.jpg|400px|thumb|16x2 LCD Module]]
 
LCD Display modules are readily available and they are dirt cheap (< $2 typically).  They come in different "resolutions" typically expressed as number of characters and number of lines.  Common ones are 1602 (16 characters in 2 lines) and 2004 (20 characters in 4 lines).
 
LCD Display modules are readily available and they are dirt cheap (< $2 typically).  They come in different "resolutions" typically expressed as number of characters and number of lines.  Common ones are 1602 (16 characters in 2 lines) and 2004 (20 characters in 4 lines).
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These can of course be "driven" by an STM32 by interfacing these pins directly, but at a minimum that would tie up 8 [[GPIO]] pins for one display.
 
These can of course be "driven" by an STM32 by interfacing these pins directly, but at a minimum that would tie up 8 [[GPIO]] pins for one display.
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To cut down on the number of pins needed a [[GPIO]] extender can be used and because this approach is quite a lot easier a lot of the LCD modules come with an [[I²C]] [[GPIO]] extender already attached.
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[[File:I2C extender on LCD display.webp|400px]]
  
 
== Miscellaneous Links ==
 
== Miscellaneous Links ==

Revision as of 04:54, 2 June 2022

16x2 LCD Module

LCD Display modules are readily available and they are dirt cheap (< $2 typically). They come in different "resolutions" typically expressed as number of characters and number of lines. Common ones are 1602 (16 characters in 2 lines) and 2004 (20 characters in 4 lines).

The modules are interfaces by an 8 bit parallel data bus (can be operated in 4 bit mode) and some control signals:

116X2-LCD-Pinouts.png

These can of course be "driven" by an STM32 by interfacing these pins directly, but at a minimum that would tie up 8 GPIO pins for one display.

To cut down on the number of pins needed a GPIO extender can be used and because this approach is quite a lot easier a lot of the LCD modules come with an I²C GPIO extender already attached.

I2C extender on LCD display.webp

Miscellaneous Links