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Correct ARM STM32 I2C frequency. (#7080) 

It was beleaved that this setting result in a 400Khz I2C bus.

This was incorrect, actual frequency measure with a logic analyzer was around 150Khz.

This is derived from the excel sheet linked in the .h file.
Also confirmed with the ST IDE.
daktil_manuform
yiancar 2019-10-31 16:19:57 +00:00 committed by Yan-Fa Li
parent 2ce6adff2b
commit 1acafc94f4
1 changed files with 5 additions and 5 deletions
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10
drivers/arm/i2c_master.h
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@ -73,19 +73,19 @@
// The default timing values below configures the I2C clock to 400khz assuming a 72Mhz clock
// For more info : https://www.st.com/en/embedded-software/stsw-stm32126.html
# ifndef I2C1_TIMINGR_PRESC
# define I2C1_TIMINGR_PRESC 15U
# define I2C1_TIMINGR_PRESC 0U
# endif
# ifndef I2C1_TIMINGR_SCLDEL
# define I2C1_TIMINGR_SCLDEL 4U
# define I2C1_TIMINGR_SCLDEL 7U
# endif
# ifndef I2C1_TIMINGR_SDADEL
# define I2C1_TIMINGR_SDADEL 2U
# define I2C1_TIMINGR_SDADEL 0U
# endif
# ifndef I2C1_TIMINGR_SCLH
# define I2C1_TIMINGR_SCLH 15U
# define I2C1_TIMINGR_SCLH 38U
# endif
# ifndef I2C1_TIMINGR_SCLL
# define I2C1_TIMINGR_SCLL 21U
# define I2C1_TIMINGR_SCLL 129U
# endif
#endif