LPC Microcontrollers中的主题 SPI boot clock frequency https://community.nxp.com/t5/LPC-Microcontrollers/SPI-boot-clock-frequency/m-p/545457#M13068 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by jond on Wed Aug 19 01:50:31 MST 2015</STRONG><BR /><SPAN>Hello,</SPAN><BR /><BR /><SPAN>We're considering a switch from NAND boot to SPI EEPROM boot.</SPAN><BR /><BR /><SPAN>In the LPC32x0 user manual (UM10326), figure 131 (SPI boot procedure), fsck is defined as fosc/2.</SPAN><BR /><BR /><SPAN>As 'fosc' isn't referenced anywhere else in the document, we would like to confirm what it is before we select an EEPROM part and modify the board layout.</SPAN><BR /><BR /><SPAN>Is fosc just the external crystal oscillator frequency? For example if we use a 13MHz crystal for SYSX then will the boot SPI clock be 6.5MHz?</SPAN><BR /><BR /><SPAN>Many thanks,</SPAN><BR /><BR /><SPAN>Jon.</SPAN></BODY></HTML> Wed, 15 Jun 2016 18:28:33 GMT lpcware 2016-06-15T18:28:33Z SPI boot clock frequency https://community.nxp.com/t5/LPC-Microcontrollers/SPI-boot-clock-frequency/m-p/545457#M13068 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by jond on Wed Aug 19 01:50:31 MST 2015</STRONG><BR /><SPAN>Hello,</SPAN><BR /><BR /><SPAN>We're considering a switch from NAND boot to SPI EEPROM boot.</SPAN><BR /><BR /><SPAN>In the LPC32x0 user manual (UM10326), figure 131 (SPI boot procedure), fsck is defined as fosc/2.</SPAN><BR /><BR /><SPAN>As 'fosc' isn't referenced anywhere else in the document, we would like to confirm what it is before we select an EEPROM part and modify the board layout.</SPAN><BR /><BR /><SPAN>Is fosc just the external crystal oscillator frequency? For example if we use a 13MHz crystal for SYSX then will the boot SPI clock be 6.5MHz?</SPAN><BR /><BR /><SPAN>Many thanks,</SPAN><BR /><BR /><SPAN>Jon.</SPAN></BODY></HTML> Wed, 15 Jun 2016 18:28:33 GMT https://community.nxp.com/t5/LPC-Microcontrollers/SPI-boot-clock-frequency/m-p/545457#M13068 lpcware 2016-06-15T18:28:33Z