Editing Serial Peripheral Interface (section)

=== QPI/SQI ===
Further extending quad SPI, some devices support a "quad everything" mode where ''all'' communication takes place over 4 data lines, including commands.<ref>{{cite web |url=https://community.nxp.com/thread/336422 |title=QuadSPI flash: Quad SPI mode vs. QPI mode |date=December 2014 |website=NXP community forums |access-date=2016-02-10}}</ref>   This is variously called "QPI"{{r|D25LQ64}} (not to be confused with [[Intel QuickPath Interconnect]]) or "serial quad I/O" (SQI)<ref name="SST26VF032B">{{cite web |title=SST26VF032B / SST26VF032BA 2.5V/3.0V 32 Mbit Serial Quad I/O (SQI) Flash Memory |type=Data sheet |publisher=[[Microchip, Inc.]] |date=2017 |version=version E |url=http://ww1.microchip.com/downloads/en/DeviceDoc/20005218E.pdf |access-date=2017-02-10}}</ref>

This requires programming a configuration bit in the device and requires care after reset to establish communication.