LPC MicrocontrollersのトピックFatFs performance issue https://community.nxp.com/t5/LPC-Microcontrollers/FatFs-performance-issue/m-p/519419#M3150 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by jonas2 on Wed Jul 02 04:13:17 MST 2014</STRONG><BR /><SPAN>Hi,</SPAN><BR /><BR /><SPAN>I use FatFs R0.09 on a Cortex M3 microcontroller (LPC1778) in a multitask environment</SPAN><BR /><SPAN>(Crossworks tasking library).</SPAN><BR /><SPAN>I've noticed that some FatFs functions take a lot of time executing, e.g.</SPAN><BR /><BR /><SPAN>f_open:&nbsp;&nbsp;&nbsp;&nbsp; 40 ms</SPAN><BR /><SPAN>f_close&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 7 ms</SPAN><BR /><BR /><SPAN>Is this what I should expect or can I somehow decrease the processing time these functions "consume". The clock is running @120MHz so there is a lot of instructions needed for these functions.</SPAN><BR /><SPAN>One solution would be to open all files at startup and never close them so I only need to use f_write and f_read but I'm not sure if that is a correct way to use FatFs. Have anyone used FatFs like that?</SPAN><BR /><BR /><SPAN>Otherwise FatFs works perfectly.</SPAN><BR /><BR /><SPAN>Thanks!</SPAN><BR /><BR /><SPAN>Jonas</SPAN></BODY></HTML> Wed, 15 Jun 2016 17:38:12 GMT lpcware 2016-06-15T17:38:12Z FatFs performance issue https://community.nxp.com/t5/LPC-Microcontrollers/FatFs-performance-issue/m-p/519419#M3150 <HTML><HEAD></HEAD><BODY><STRONG>Content originally posted in LPCWare by jonas2 on Wed Jul 02 04:13:17 MST 2014</STRONG><BR /><SPAN>Hi,</SPAN><BR /><BR /><SPAN>I use FatFs R0.09 on a Cortex M3 microcontroller (LPC1778) in a multitask environment</SPAN><BR /><SPAN>(Crossworks tasking library).</SPAN><BR /><SPAN>I've noticed that some FatFs functions take a lot of time executing, e.g.</SPAN><BR /><BR /><SPAN>f_open:&nbsp;&nbsp;&nbsp;&nbsp; 40 ms</SPAN><BR /><SPAN>f_close&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; 7 ms</SPAN><BR /><BR /><SPAN>Is this what I should expect or can I somehow decrease the processing time these functions "consume". The clock is running @120MHz so there is a lot of instructions needed for these functions.</SPAN><BR /><SPAN>One solution would be to open all files at startup and never close them so I only need to use f_write and f_read but I'm not sure if that is a correct way to use FatFs. Have anyone used FatFs like that?</SPAN><BR /><BR /><SPAN>Otherwise FatFs works perfectly.</SPAN><BR /><BR /><SPAN>Thanks!</SPAN><BR /><BR /><SPAN>Jonas</SPAN></BODY></HTML> Wed, 15 Jun 2016 17:38:12 GMT https://community.nxp.com/t5/LPC-Microcontrollers/FatFs-performance-issue/m-p/519419#M3150 lpcware 2016-06-15T17:38:12Z