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Zephyr project on STM32

   Zephyr Workbench, a VSCode extension to manage Zephyr on STM32.
It enables users to easily create, develop, and debug Zephyr applications.
Main features:
  • Install host dependencies.
  • Import toolchain and SDK.
  • Create, configure, build and manage apps.
  • Debug STM32.
You can directly download it from the VSCode marketplace
For more details, visit the Zephyr Workbench

System Workbench for STM32

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Why is the pointer only 1 byte while the Size is 2 bytes? Sense?

Posted by BenoitHanridge on 2016-03-18 23:06

Hi Everyone,

This is about a HAL_SPI_Transmit().

When looking in ST’s help file STM32F103xG HAL User Manual.chm HAL_SPI_Transmit(), *pData is uint8_t of type while Size is of uint16_t type. That doesn’t make sense. How can a pointer only reach 255 while the size can go up to 65535. I don’t see any practical purpose in this. It’s funny. Isn’t a 1MB memory address a lot wider than 1 byte? Sure it is, not? So what exactly is pData then?

Greets,
Ben

ps: The ST help screenshot for HAL_SPI_Transmit() is attached.

HAL_SPI_Transmit_for_my_stm32f1xx.png (273.82 Kb)
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Posted by Reynard on 2016-03-19 11:23

pData is a pointer pointing to an array of 8 bit bytes or similar object.

The pointer itself is probably 32 bits.

Cheers

Reynard

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