topic USB ISP mode without external crystal? in LPC Microcontrollers https://community.nxp.com/t5/LPC-Microcontrollers/USB-ISP-mode-without-external-crystal/m-p/514323#M633 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by Dmaroto on Thu Aug 13 04:28:03 MST 2015</STRONG><BR /><SPAN>I am trying to use the USB ISP mode to program an application for the first time and the micro (LPC1547) does not seem to enter into USB ISP mode.</SPAN><BR /><BR /><SPAN>I have checked the voltages and states of ISP_0 and ISP_1 during power up and all seems to be as it should.</SPAN><BR /><BR /><SPAN>I did see this note in section 5.4 of the user manual: </SPAN><BR /><BR /><STRONG>Remark:</STRONG><SPAN> In USB ISP mode, an external 12 MHz crystal is required&nbsp; to communicate with the external storage device. (I did not consider the chip Flash as "external" when designing the circuit).</SPAN><BR /><BR /><SPAN>Can the LPC1547 actually start in USB ISP mode without an external clock?</SPAN><BR /><BR /><SPAN>Thank you for your help.</SPAN></BODY></HTML> Wed, 15 Jun 2016 17:12:01 GMT lpcware 2016-06-15T17:12:01Z USB ISP mode without external crystal? https://community.nxp.com/t5/LPC-Microcontrollers/USB-ISP-mode-without-external-crystal/m-p/514323#M633 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by Dmaroto on Thu Aug 13 04:28:03 MST 2015</STRONG><BR /><SPAN>I am trying to use the USB ISP mode to program an application for the first time and the micro (LPC1547) does not seem to enter into USB ISP mode.</SPAN><BR /><BR /><SPAN>I have checked the voltages and states of ISP_0 and ISP_1 during power up and all seems to be as it should.</SPAN><BR /><BR /><SPAN>I did see this note in section 5.4 of the user manual: </SPAN><BR /><BR /><STRONG>Remark:</STRONG><SPAN> In USB ISP mode, an external 12 MHz crystal is required&nbsp; to communicate with the external storage device. (I did not consider the chip Flash as "external" when designing the circuit).</SPAN><BR /><BR /><SPAN>Can the LPC1547 actually start in USB ISP mode without an external clock?</SPAN><BR /><BR /><SPAN>Thank you for your help.</SPAN></BODY></HTML> Wed, 15 Jun 2016 17:12:01 GMT https://community.nxp.com/t5/LPC-Microcontrollers/USB-ISP-mode-without-external-crystal/m-p/514323#M633 lpcware 2016-06-15T17:12:01Z Re: USB ISP mode without external crystal? https://community.nxp.com/t5/LPC-Microcontrollers/USB-ISP-mode-without-external-crystal/m-p/514324#M634 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by R2D2 on Thu Aug 13 05:13:01 MST 2015</STRONG><BR /><HR /><SPAN style="color: #0000ff;"><STRONG>Quote: Dmaroto</STRONG><BR />Can the LPC1547 actually start in USB ISP mode without an external clock?<BR /></SPAN><HR /><BR /><BR /><SPAN>No&nbsp; :(( </SPAN><BR /></BODY></HTML> Wed, 15 Jun 2016 17:12:02 GMT https://community.nxp.com/t5/LPC-Microcontrollers/USB-ISP-mode-without-external-crystal/m-p/514324#M634 lpcware 2016-06-15T17:12:02Z