CP2400/2 SPI NSS Pin Connection

by <a href="http://community.silabs.com/t5/Welcome-and-Announcements/Community-Ranking-System-and-Recognition-Program/m-p/140490#U140490"><font color="#000000"><font size="2">Hero Employee</font></font> </a> Jiehui on ‎06-13-2017 09:28 PM

Question

Can the NSS pin of CP240x be connected to GND?

Answer

No. CP2400/2 devices have a 4-wire Serial Peripheral Interface (SPI) which provides access to the internal registers and memory. The active-low slave-select (NSS) signal allows support for multiple slave devices on a single bus. It is also used to detect the start and end of a SPI transfer for CP2400/2, and should be connected to the SPI master instead of connection to a static low level signal, e.g. GND. The SPI transaction ends when NSS is de-asserted.