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SPI1 and I2C1

Posted: Fri Apr 24, 2020 11:05 am
by cptcredible
Why are there two MOSI1 pins, two MISO1 pins, two SDA1 pins and two SCL1 pins ? how do these interact ? can you choose witch one to use ?

Re: SPI1 and I2C1

Posted: Fri Apr 24, 2020 12:24 pm
by fpiSTM
Well I guess you talk about the BluePill and the STM32F103C8.
The MCU contains several type of integrated peripherals (SPI, I2C, Timers, ...).
All those peripherals can be "mapped" on different pins.
For example the I2C1 SDA signal can be mapped to PB7 or PB9. This simply allows you to have some option for you wiring depending of your needs.

See Slode 6 of this presentation:
https://www.stmicroelectronics.com.cn/c ... e-GPIO.pdf

Re: SPI1 and I2C1

Posted: Sat Apr 25, 2020 11:42 am
by cptcredible
Thanks!