while spi slave mode, no problem with ss pin connecting to ground

[mdever]

I'm going to configure nRF51822 chip as a spi slave.

And there are no more pins for the connector. So I am trying to connect SS pin to the ground pin, instead to connect to SS pin of SPI master chip.

I will try with my EVB but I want to receive the comment from the chip maker, Nordic.

[Einar Thorsrud]

The SPI peripheral requires the HFCLK, and requests it when SS (CSN) is asserted. Thus you would see a significant power consumption if SS is tied to ground. Also, many designs use the chip select pin as a wake-up source.

You could probably find a work around, depending on your requirements. Moreover, if you do not care about power consumption I do not see a big problem (though I have not tested it).