How many SPI Interfaces does the BL65x support

The BL654 Data sheet lists four SPI Interfaces (up to 8 Mbps) are supported. The data sheet is provided as a hardware guide and refers to the hardware itself. The Nordic nRF52840 MCU supports up to 4 SPI instances. However, the actual number of SPI interfaces depends on what SW is used for application development. If using smartBASIC for development there is one SPI instance that can be configured as SPI master.

The SPI port is opened via smartBASIC function SPIOPEN(). This function includes parameters that allow configuration of SPI Mode, SPI Clock Rate and SPI Flags. SPI pins cannot be configured and use the pins that are specified in the BL65x Data Sheet. Refer to smartBASIC Core Functionality Specification. SPI_CS is not controlled in smartBASIC firmware and must be controlled by the application through use of SIO pins.

For applications developed using Nordic SDK or Nordic Zephyr SDK the nRF528xx MCU supports up to 4 SPI Instances. There can be up to 4 SPI Master interfaces (SPIM Master) and up to 3 SPI Slave interfaces (SPIS) but not all at once. There are four total SPI interfaces and master/slave combinations are shared across those four instances. The nRF528xx also contains two I2C Instances which are shared with the two lower SPI instances via TWI. Refer to the latest nRF52xx data sheet for details.