Chip Select pin in SDK 11.0

RE: Chip Select pin in SDK 11.0

tesc — Tue, 12 Jul 2016 12:06:51 GMT

Hi,

The SPI master example (examples\peripheral\spi) uses the SPI master driver. Slave select is handled by the driver, i.e. SPI_CS_PIN is set low right before the transfer starts and set back high when transfer is done.

Regards, Terje

RE: Chip Select pin in SDK 11.0

Pradeep Chl — Tue, 12 Jul 2016 04:50:50 GMT

CS pin is not set high in spi_event_handler(), It is a small function that is called after data is transferred from m_tx_buf. Please correct me.

At line no: 540 in nrf_drv_spi.c, the function nrf_gpio_pin_clear(p_cb->ss_pin) clears the CS pin.

Without EasyDMA: At line no: 415 in nrf_drv_spi.c, the function nrf_gpio_pin_set(p_cb->ss_pin) sets the CS pin.

With EasyDMA: At line no: 502 in nrf_drv_spi.c, the function nrf_gpio_pin_set(p_cb->ss_pin) sets the CS pin.

Clearing CS and Setting CS pin happens in the same function nrf_drv_spi_transfer() ?

Thanks,

RE: Chip Select pin in SDK 11.0

James Yu — Mon, 11 Jul 2016 17:30:11 GMT

The CS pin is pulled low on nrf_drv_spi_transfer() and set high on spi_event_handler().