Wireless MCU to control slave device through SPI

RE: Wireless MCU to control slave device through SPI

nothingmuchyou — Mon, 25 Jan 2021 15:54:24 GMT

bjorn-spockeli It would be nice if this spec was in the product specification for the nrf52 series itself, but thank you for pointing me to this page!

RE: Wireless MCU to control slave device through SPI

bjorn-spockeli — Fri, 22 Jan 2021 08:25:25 GMT

nothingmuchyou: Please see the Performance section under the Migrating from the nRF51 Series to the nRF52 Series section. The Advanced High-performance Bus(AHB) runs at 64MHz, but the Advanced Peripheral Bus(APB) runs at 16MHz.

RE: Wireless MCU to control slave device through SPI

nothingmuchyou — Wed, 20 Jan 2021 20:28:45 GMT

Can you point to the section in the product specification that specifies this

[quote userid="7571" url="~/f/nordic-q-a/17178/wireless-mcu-to-control-slave-device-through-spi/65986#65986"]It is correct that the nRF52's M4 core runs at 64 MHz, but the peripheral bus runs at 16MHz.[/quote]

RE: Wireless MCU to control slave device through SPI

bjorn-spockeli — Thu, 20 Oct 2016 13:55:16 GMT

No, all the peripherals on the nRF52 runs at 16MHz, thus the absolute most you could ever hope to achieve would be one toggle of the output value every clock cycle.

RE: Wireless MCU to control slave device through SPI

varkong — Thu, 20 Oct 2016 13:41:29 GMT

Thanks for the reply. Is it not possible to use the system clock (64 MHz) to program a GPIO, and rapidly switching it on and off essentially creating a pseudo CS or SCLK line?

RE: Wireless MCU to control slave device through SPI

bjorn-spockeli — Thu, 20 Oct 2016 09:18:00 GMT

It is correct that the nRF52's M4 core runs at 64 MHz, but the peripheral bus runs at 16MHz.

No, the maximum speed of the SPI Master on the nRF52 is 8Mbps, i.e. at 8 MHz.
Not possible, see 1.
We do not currently have any ICs that have a SPI peripheral able to run at the speed that you require.
Yes, the nRF52 can be debugged. The nRF52 supports OTA DFU ( Over-the-Air Device Firmware Update), but this requires the device to be programmed initially through a wired connection.

Best regards

Bjørn