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CHANGELOG.md

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+# Change Log
+All notable changes to this project will be documented in this file.
+
+The format is based on [Keep a Changelog](http://keepachangelog.com/)
+and this project adheres to [Semantic Versioning](http://semver.org/).
+
+## [Unreleased]
+### Fixed
+* Fix build error of "cannot find -lmy_pico_stdio_usb_headers"
+* Delete obsolete CENTER button completely not to disturb other button actions when pullup is not attached. [issue](https://github.com/elehobica/RPi_Pico_WAV_Player/issues/4)
+
+### Changed
+* Support pico-sdk 1.5.1 (previously 1.4.0)
+* Update FatFs R0.15 (previously R0.14b)
+* Changed to use submodules for pico_fatfs and pico_st7735_80x160 libraries
+* Remove external pullup resistors for PLUS, MINUS buttons
+* Remove external pullup resistors for MISO, MOSI of microsd SPI
+* Clean up libraries. pico_fatfs and pico_st7735_80x160 are switched to submodules.
+* Change I2C DMA scheme from single buffer to double buffers
+
+
+## [v0.9.2] - 2023-11-25
+### Fixed
+* Small fix for fatfs CS handling
+
+
+## [v0.9.1] - 2021-09-21
+### Added
+* Add gpio_disable_pulls() to SD-Card SPI pins
+
+### Changed
+* Adjust ADC conversion coefficient for static battery check
+
+
+## [v0.9.0] - 2021-06-20
+### Added
+* Support ChargeMode which allows to remove USB charge selection switch
+
+### Changed
+* No hardware modification needed in Raspberry Pi Pico board
+- External circuit around battery charger revised to be compliant to pico-datasheet.pdf
+- Use built-in battery voltage check circuit (static battery check) as default
+* Increase display charactor length of title, artist and album. add measure to prevent buffer overflow
+* Remove GPIO center button and integrated into GP26 ADC level detection to detect wake up trigger
+
+
+## [v0.8.1] - 2021-06-03
+* Initial release