版本 39a03a2d244855ae0d049a76a6b88fef4f993a77
Changes from 39a03a2d244855ae0d049a76a6b88fef4f993a77 to 111213d58d512d897ba85724202b0d09c0e66022
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title: SPI
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關聯在哪?舉例。
圖例
SPI 為資料傳輸協定,有著以下幾點特色:
- 同步式
- 全雙工
- 可以半雙工或單工
- 主從式
- 多個 master
- dynamic change of master/ slave
- 多個 master
- 8 master baud rate prescalers
- slave mode frequency
- SPI TI / motorola mode
- MSB-first or LSB-first
- Hardware CRC
- DMA capability
.. BIDI mode / RXONLY (p. 801)
..
SPI 匯流排是由Motorla所命名的匯流排名稱。它是一個可同步序列資料連結的標準也可以
在全雙功的模式下運作。在資料傳輸的過程當中是以Master/Slave的角色來傳遞資料,必
須要由Master來主動提取資料,而Slave只能被動地接收命令或傳送資料。而傳送資料的同
時,Master也可以傳送命令給Slave無須等對方完全收到資料才進行下一步。
..
I2S feature
Device overview
====
|STM32F40x block diagram|
.. |STM32F40x block diagram| image:: /embedded/SPI/STM32F40x block diagram.png
SPI functional description
====
|SPI block diagram|
.. |SPI block diagram| image:: /SPI block diagram.png
MISO: Master In / Slave Out data
MISO: Master Out / Slave In data
SCK: Serial Clock ( Master -> Slave )
NSS: *optional* select slave, low-driven
.. image:: /SPI_single_slave.svg
Interface
=========
SPI 匯流排有規範4個腳位
SCLK: serial clock (output from master);
MOSI: master output, slave input (output from master);
MISO: master input, slave output (output from slave);
SS: slave select (active low, output from master).
|SPI block diagram|
.. |SPI block diagram| image:: /SPI block diagram.png
STM32F4XX
=========
It has up to 3 SPIs (37.5 Mbits/s), 2 with muxed full-duplex I2S to achieve audio class
accuracy via internal audio PLL or external clock
SPI1 can communicate at up to 37.5 Mbits/s, SPI2 and SPI3 can communicate at up to 21 Mbit/s.
Operation
=========
Data transmission
-----------------
Clock polarity and phase
~~~~~~~~~~~~~~~~~~~~~~~~
Mode numbers
~~~~~~~~~~~~~
..
may know used structure
guess: interrupt
Independent slave SPI configuration
-----------------------------------
Daisy chain SPI configuration
------------------------------
Valid SPI communication
-----------------------
interrupts
----------
Example of bit-banging the SPI master protocol
===============================================
Reference
=========
- `Serial Peripheral Interface Bus - Wikipedia, the free encyclopedia <http://en.wikipedia.org/wiki/Serial_Peripheral_Interface_Bus>`_
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