I SPI

The Serial Peripheral Interface (SPI) bus was put together by Motorola (Freescale/NXP/Qualcomm) in the 1980s for communicating between a processor and one or more external peripherals. SPI is intended for short distance communication, typically between chips on the same board.

SPI is similar to the I2C bus and it has advantages, drawbacks, and similarities:

SPI Advantages:

  • Higher speed
  • No addresses
  • No pullup resistors
  • Transmit and receive simultaneously

SPI Drawbacks:

  • More pins necessary
  • There are at least 4 ways to set them up

Similarities between SPI and I2C:

  • Need to send out dummy data to retrieve results
  • Reduced pin count and smaller packages compared to parallel buses
  • Might require an oscilloscope to check the signal timing

The topology of the SPI circuit is a bus consisting of a master and one or more slaves. The signals on the bus are called Master Out Slave In (MOSI), Master In Slave Out (MISO), Clock, and Select.

In the following figures I show two typical implementations of SPI with one and three slave peripherals. (A uP is a microprocessor.)

稿源:Embedded.fm Blog (源链) | 关于 | 阅读提示

本站遵循[CC BY-NC-SA 4.0]。如您有版权、意见投诉等问题,请通过eMail联系我们处理。
酷辣虫 » 综合编程 » I SPI

喜欢 (0)or分享给?

专业 x 专注 x 聚合 x 分享 CC BY-NC-SA 4.0

使用声明 | 英豪名录