nfr51822 SPI multi_slave conrtol

[ShiuChinWang]

hi First,I apology for my poor English...

I want to make a project to connect 2 device.

With a sensor from TI , which comes out the sensed signal . Transfer the data to the nrf51822 chip via SPI (So does the TI sensor ,it signal output to the SPI bus)

And then , after the signal processing from nrf51822 cpu . The nrf chip outputs the processed signal to the SPI bus . The SPI bus will deliver the data to the OLED display (The OLED is used SPI chip ssd1306)

I have no idea about what should I do.

Should I use all three module ? [spi Master] [spi Slave] [spi master with spi slave]

Sensor & OLED will be the SPI SLAVE (so I can focus them on the slave example code) nrf51822 will be the SPI MASTER

Is it right?

another question Does the it can be real-time transferring or close to real-time?

[awneil]

SPI is a bus - that is, a communication channel specifically intended to be shared by multiple devices.

It is very well-established and widely used - there are plenty of sites that explain how it works; eg,

en.wikipedia.org/.../Serial_Peripheral_Interface_Bus

The datasheets for your sensor & display will give specific details of their particular usage of the SPI.

Yes, your nRF51822 will be the Master in this case; that is, it generates the clocks & chip-selects (aka slave-selects).

I would strongly recommend that you don't try to tackle both sensor and display at the same time: start with one; then, when that's working, add the other.

[awneil]

infocenter.nordicsemi.com/.../hardware_driver_spi_master.html

In particular, note: "The SPI master driver can automatically control the Slave Select signal (see nrf_drv_spi_config_t::ss_pin). This feature can only be used if there is exactly one slave. If there are multiple slaves, the Slave Select signal must be controlled externally"