On 7 March 2012 08:07, salvador <salva...@telecable.es> wrote: > > Hello, > > after reading and looking at the examples in this data sheet: PIC32MX > Section 3. Memory Organization > > http://ww1.microchip.com/downloads/en/DeviceDoc/61115F.pdf > > i think the settings in pic32mx.cfg are wrong, but ... > > Suppose we have 16K of RAM. ( _WORKAREASIZE 0x4000). > > set _PIC32MX_DATASIZE > 0x800 > 2K > set _PIC32MX_PROGSIZE [expr ($_WORKAREASIZE - > $_PIC32MX_DATASIZE)] 14K > > > # BMXDKPBA: 2k kernel data @ 0xa0000800 > mww 0xbf882010 $_PIC32MX_DATASIZE > > OK: 2k kernel data from 0xa0000000 to 0xa0000800 > > > # BMXDUDBA: 16k kernel program @ 0xa0000800 > mww 0xbf882020 $_PIC32MX_PROGSIZE > Why not 16K (_WORKAREASIZE)? >
because we cannot use the first 2k (by design). BMXDKPBA<10:0> are read only and always read as zero. > Now we have kernel program memory from 2k to 14k and from 14k to 16k in > user space 2k. > Kernel program memory starts at 0xa0000800. Size 12k. > > # BMXDUPBA: 0k user program > mww 0xbf882030 $_PIC32MX_PROGSIZE > Why not 16K (_WORKAREASIZE)? > > Now we have 2k user program memory, and 0k user data memory. > user program memory size is defined as BMXDUPBA - BMXDUDBA > > $_TARGETNAME configure -work-area-phys 0xa0000800 -work-area-size > $_PIC32MX_PROGSIZE -work-area-backup 0 > > We set -work-area-size to 14K but we have only 12k. > > > At first glance, with actual driver code, this is not a problem if we have > 16k RAM or more memory. But with 8k or 4k probably it will not work. > For example with 4K RAM we end up setting -work-area-size to 2K but there is > no kernel program memory at all. > > I am wrong? > > Thanks, Salvador. > It has been a while, however looking at the cfg again the only issue i see are typo's. 1. kernel data is 2k but should start @ 0xa0000000 not 0xa0000800. 2. kernel data should say 14k not 16k I will commit a patch for the above. Cheers Spen ------------------------------------------------------------------------------ Virtualization & Cloud Management Using Capacity Planning Cloud computing makes use of virtualization - but cloud computing also focuses on allowing computing to be delivered as a service. http://www.accelacomm.com/jaw/sfnl/114/51521223/ _______________________________________________ OpenOCD-devel mailing list OpenOCD-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openocd-devel
