https://community.nxp.com/t5/i-MX-Processors/Input-timing-in-DDR-mode-with-loopback-DQS-sampling/m-p/1228447#M169192 <P>Hello,</P><P>&nbsp;</P><P>I have two questions about QuadSPI's Input timing in DDR mode with loopback DQS sampling.<BR />No1<BR />Is it a mode that can be used with serial flash without DQS?<BR />No2<BR />Can the QSPI_A_DQS (EPDC1_DATA04) pin be open when used in this mode?<BR />Or does the QSPI_A_DQS (EPDC1_DATA04) pin connect to any pin?</P><P>&nbsp;</P><P><SPAN>Regards,</SPAN></P><P>Goto</P> Tue, 09 Feb 2021 03:52:21 GMT goto11 2021-02-09T03:52:21Z https://community.nxp.com/t5/i-MX-Processors/Input-timing-in-DDR-mode-with-loopback-DQS-sampling/m-p/1228447#M169192 <P>Hello,</P><P>&nbsp;</P><P>I have two questions about QuadSPI's Input timing in DDR mode with loopback DQS sampling.<BR />No1<BR />Is it a mode that can be used with serial flash without DQS?<BR />No2<BR />Can the QSPI_A_DQS (EPDC1_DATA04) pin be open when used in this mode?<BR />Or does the QSPI_A_DQS (EPDC1_DATA04) pin connect to any pin?</P><P>&nbsp;</P><P><SPAN>Regards,</SPAN></P><P>Goto</P> Tue, 09 Feb 2021 03:52:21 GMT https://community.nxp.com/t5/i-MX-Processors/Input-timing-in-DDR-mode-with-loopback-DQS-sampling/m-p/1228447#M169192 goto11 2021-02-09T03:52:21Z https://community.nxp.com/t5/i-MX-Processors/Input-timing-in-DDR-mode-with-loopback-DQS-sampling/m-p/1228493#M169200 <P><a href="https://community.nxp.com/t5/user/viewprofilepage/user-id/172587">@goto11</a>&nbsp;<BR />Hello,<BR /><BR /></P> <P>&nbsp;&nbsp; It is possible to use DDR QSPI flash without DQS, assuming <BR />the loopback. Add 18pf on the DQS pin.</P> <P>Regards,<BR />Yuri.</P> Tue, 09 Feb 2021 04:27:04 GMT https://community.nxp.com/t5/i-MX-Processors/Input-timing-in-DDR-mode-with-loopback-DQS-sampling/m-p/1228493#M169200 Yuri 2021-02-09T04:27:04Z