What is the memory zone not affected by the tools on XU216 processor ?
Based on dfu.xc file I suppose that the range is 0x7FFC8 to 0x7FFFF. After receiving a XMOS_DFU_RESETINTODFU command I write specific pattern in this area, but after CPU reset this area is most of the time reset to 0.
How to explain that this supposed area is reset after a CPU reset writing in PLL register ?
I try to write directly in this area just before reboot and the result is the same
#define FLAG_ADDRESS 0x7FFCC
unsigned x =0x11042011;
asm volatile("stw %0, %1" :: "r"(x), "r"(FLAG_ADDRESS));
I also test removing the pattern writing in DFU handler, but the area is always reset to 0 after reboot
Any ideas how to explain this problem ?