nRF52832: 3 x SPI Master instances

RE: nRF52832: 3 x SPI Master instances

jinvers — Thu, 20 Jun 2024 20:57:38 GMT

Thank you Kenneth.

Regards,

Joel

RE: nRF52832: 3 x SPI Master instances

Kenneth — Thu, 20 Jun 2024 15:41:12 GMT

Just quickly looking at https://infocenter.nordicsemi.com/topic/sdk_nrf5_v17.1.0/spi_master_example.html

In main() I would have changed to:
spi_config.ss_pin = NRF_DRV_SPI_PIN_NOT_USED;

Then each time you want to write to a spi slave device you simply do something like:

// spi device #1

csn_pin1 = 0;
nrf_drv_spi_transfer(&spi, m_tx_buf, m_length, m_rx_buf, m_length))
csn_pin1 = 1;

// spi device #2

csn_pin2 = 0;
nrf_drv_spi_transfer(&spi, m_tx_buf, m_length, m_rx_buf, m_length))
csn_pin2 = 1;

and so on.

Kenneth

RE: nRF52832: 3 x SPI Master instances

jinvers — Thu, 20 Jun 2024 14:28:52 GMT

Hello Kenneth,

Thank you for your reply.

Do you have any example code? In my case I would use the SDK 17.1.0 and the Segger IDE.

Regards,

Joel

RE: nRF52832: 3 x SPI Master instances

Kenneth — Thu, 20 Jun 2024 13:02:35 GMT

Hello,

The nRF52832 have up to 3 SPIM instances:
https://docs.nordicsemi.com/bundle/ps_nrf52832/page/peripheral_interface.html#d932e91

Note however that these instances overlap with other types of peripherals (e.g. twi, uart), so that is something you may need to consider if you are using any those already.

It's possible to share CLK, MISO and MOSI signales between several slaves, as long as only one of the slaves is selected by the Chip Select (CS) pin at any time. In such case the most common is to use only one SPIM instance, and then only change the CS# pin between transfer.

Kenenth