topic Re: LPC1778 - INPUT INVERSION ON SSP0_SSEL P1[21] in LPC Microcontrollers https://community.nxp.com/t5/LPC-Microcontrollers/LPC1778-INPUT-INVERSION-ON-SSP0-SSEL-P1-21/m-p/522611#M5247 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by MikeSimmonds on Fri Sep 18 09:07:38 MST 2015</STRONG><BR /><SPAN>Why not leave the not gate footprint on the PCB and just bridge input to output with a link wire just in case?</SPAN><BR /></BODY></HTML> Wed, 15 Jun 2016 17:57:08 GMT lpcware 2016-06-15T17:57:08Z LPC1778 - INPUT INVERSION ON SSP0_SSEL P1[21] https://community.nxp.com/t5/LPC-Microcontrollers/LPC1778-INPUT-INVERSION-ON-SSP0-SSEL-P1-21/m-p/522608#M5244 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by wwwenrico on Thu Sep 17 03:58:20 MST 2015</STRONG><BR /><SPAN>Hi,</SPAN><BR /><BR /><SPAN>I'm designing a board based on the LPC1778 microcontroller.</SPAN><BR /><BR /><SPAN>I have to interface the LPC1778 to an external module that acts as an SSP master.</SPAN><BR /><BR /><SPAN>I'll configure the SSP0 interface as a slave.</SPAN><BR /><BR /><BR /><SPAN>The SSEL signal of the master is inverted with respect to the standard.</SPAN><BR /><SPAN>In fact, the idle state is 0 Volt and not 3.3 Volt.</SPAN><BR /><BR /><BR /><SPAN>QUESTION:</SPAN><BR /><SPAN>Can I use the IOCON_P1_21 register to invert the input signal and have the SSEL inverted?</SPAN><BR /><BR /><BR /><SPAN>Best Regards,</SPAN><BR /><SPAN>Enrico Migliore</SPAN></BODY></HTML> Wed, 15 Jun 2016 17:57:06 GMT https://community.nxp.com/t5/LPC-Microcontrollers/LPC1778-INPUT-INVERSION-ON-SSP0-SSEL-P1-21/m-p/522608#M5244 lpcware 2016-06-15T17:57:06Z Re: LPC1778 - INPUT INVERSION ON SSP0_SSEL P1[21] https://community.nxp.com/t5/LPC-Microcontrollers/LPC1778-INPUT-INVERSION-ON-SSP0-SSEL-P1-21/m-p/522609#M5245 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by DF9DQ on Thu Sep 17 12:04:04 MST 2015</STRONG><BR /><SPAN>This will work. The inverter option in the IOCON registers also works on the special functions like SSEL.</SPAN></BODY></HTML> Wed, 15 Jun 2016 17:57:07 GMT https://community.nxp.com/t5/LPC-Microcontrollers/LPC1778-INPUT-INVERSION-ON-SSP0-SSEL-P1-21/m-p/522609#M5245 lpcware 2016-06-15T17:57:07Z Re: LPC1778 - INPUT INVERSION ON SSP0_SSEL P1[21] https://community.nxp.com/t5/LPC-Microcontrollers/LPC1778-INPUT-INVERSION-ON-SSP0-SSEL-P1-21/m-p/522610#M5246 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by wwwenrico on Thu Sep 17 20:10:43 MST 2015</STRONG><BR /><SPAN>Hi DF9DW,</SPAN><BR /><BR /><SPAN>thank you for your answer.</SPAN><BR /><BR /><SPAN>Are you 100% sure about that?</SPAN><BR /><BR /><SPAN>I'm removing the NOT gate from the schematics and I would like to be completely sure that I won't have to redesign the PCB.</SPAN><BR /><BR /><SPAN>Best Regards,</SPAN><BR /><SPAN>Enrico Migliore</SPAN></BODY></HTML> Wed, 15 Jun 2016 17:57:07 GMT https://community.nxp.com/t5/LPC-Microcontrollers/LPC1778-INPUT-INVERSION-ON-SSP0-SSEL-P1-21/m-p/522610#M5246 lpcware 2016-06-15T17:57:07Z Re: LPC1778 - INPUT INVERSION ON SSP0_SSEL P1[21] https://community.nxp.com/t5/LPC-Microcontrollers/LPC1778-INPUT-INVERSION-ON-SSP0-SSEL-P1-21/m-p/522611#M5247 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by MikeSimmonds on Fri Sep 18 09:07:38 MST 2015</STRONG><BR /><SPAN>Why not leave the not gate footprint on the PCB and just bridge input to output with a link wire just in case?</SPAN><BR /></BODY></HTML> Wed, 15 Jun 2016 17:57:08 GMT https://community.nxp.com/t5/LPC-Microcontrollers/LPC1778-INPUT-INVERSION-ON-SSP0-SSEL-P1-21/m-p/522611#M5247 lpcware 2016-06-15T17:57:08Z Re: LPC1778 - INPUT INVERSION ON SSP0_SSEL P1[21] https://community.nxp.com/t5/LPC-Microcontrollers/LPC1778-INPUT-INVERSION-ON-SSP0-SSEL-P1-21/m-p/522612#M5248 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by wwwenrico on Mon Sep 21 07:11:27 MST 2015</STRONG><BR /><SPAN>Hi,</SPAN><BR /><BR /><SPAN>yes, I'll do that.</SPAN><BR /><BR /><SPAN>Best Regards,</SPAN><BR /><SPAN>Enrico Migliore</SPAN></BODY></HTML> Wed, 15 Jun 2016 17:57:08 GMT https://community.nxp.com/t5/LPC-Microcontrollers/LPC1778-INPUT-INVERSION-ON-SSP0-SSEL-P1-21/m-p/522612#M5248 lpcware 2016-06-15T17:57:08Z Re: LPC1778 - INPUT INVERSION ON SSP0_SSEL P1[21] https://community.nxp.com/t5/LPC-Microcontrollers/LPC1778-INPUT-INVERSION-ON-SSP0-SSEL-P1-21/m-p/522613#M5249 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by wwwenrico on Thu Sep 24 07:03:44 MST 2015</STRONG><BR /><SPAN>Hi,</SPAN><BR /><BR /><SPAN>I might also use 2 pins of the microcontroller and build a software inverter interrupt driven.</SPAN><BR /><BR /><BR /><SPAN>Best Regards,</SPAN><BR /><SPAN>Enrico Migliore</SPAN><BR /><BR /></BODY></HTML> Wed, 15 Jun 2016 17:57:09 GMT https://community.nxp.com/t5/LPC-Microcontrollers/LPC1778-INPUT-INVERSION-ON-SSP0-SSEL-P1-21/m-p/522613#M5249 lpcware 2016-06-15T17:57:09Z Re: LPC1778 - INPUT INVERSION ON SSP0_SSEL P1[21] https://community.nxp.com/t5/LPC-Microcontrollers/LPC1778-INPUT-INVERSION-ON-SSP0-SSEL-P1-21/m-p/522614#M5250 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by starblue on Sat Sep 26 07:35:17 MST 2015</STRONG><BR /><SPAN>That sounds a bit contorted.</SPAN><BR /><SPAN>Why don't you drive the chip select from software anyway?</SPAN></BODY></HTML> Wed, 15 Jun 2016 17:57:10 GMT https://community.nxp.com/t5/LPC-Microcontrollers/LPC1778-INPUT-INVERSION-ON-SSP0-SSEL-P1-21/m-p/522614#M5250 lpcware 2016-06-15T17:57:10Z