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Rasp-Hack-Afficheur-LCD-Breadboard (voir la source)
Version du 21 janvier 2017 à 11:30
, 21 janvier 2017 à 11:30→MCP23017 IO Expander + LCD
= MCP23017 IO Expander + LCD =
= MCP23017 IO Expander + LCD =
{{traduction}}
== A propos du MCP23017 ==
== A propos du MCP23017 ==
One problem with using a character LCD is that you give up a lot of GPIO pins to talk to the LCD. Four pins are used to send data, two pins are used for write and clock signals, and another pin or three are used for the backlight for a total of ~6-9 total pins! On a platform like the Raspberry Pi model A/B with only a dozen or so GPIO pins you can quickly run out of pins for other parts of your project. However with chips like the MCP23008 or {{pl|218|MCP23017}} you can easily add extra GPIO pins to your development board through an I2C interface!
One problem with using a character LCD is that you give up a lot of GPIO pins to talk to the LCD. Four pins are used to send data, two pins are used for write and clock signals, and another pin or three are used for the backlight for a total of ~6-9 total pins! On a platform like the Raspberry Pi model A/B with only a dozen or so GPIO pins you can quickly run out of pins for other parts of your project. However with chips like the MCP23008 or {{pl|218|MCP23017}} you can easily add extra GPIO pins to your development board through an I2C interface!