Ivor HewittAug 17, 2025

Grr. ok with openocd I can probe the NAND over jtag, and see the info....

> nand probe 0
NAND flash device 'NAND 256MiB 3.3V 8-bit (Hynix)' found

> nand info 0 0 1
#0: NAND 256MiB 3.3V 8-bit (Hynix) pagesize: 2048, buswidth: 8, erasesize: 131072
#0: 0x00000000 (128kB) erase state unknown (block condition unknown)
#1: 0x00020000 (128kB) erase state unknown (block condition unknown)

but I can't read/dump. ☹️
> nand dump 0 test.dump 0x20000 0x800
reading NAND flash page failed

Not sure what could be wrong/need changing. 😡 This is driving me mad, although I'm not an openocd expert to know why the info would work but read not.

#openocd #debugging #hacking #jtag

Show threadIvor HewittAug 19, 2025
huzzah! I now can read the NAND flash on the capsure #rm200!
still not quite perfect (some comments about 'error detected') so I'm not confident enough to try a flash write just yet.
That wasn't *too* excruciating to work through. 😬
Must be time for another blog update, didn't write one last week since I was still so frustrated with getting this working.
Show threadIvor HewittAug 20, 2025
Haha!!! Oh boy, right blog #2 underway....
@azzeloof The cheap capsure can indeed be booted as a QC model after a bit of flash magic. 🤣
This was a *lot* of fun. and frustration. Only bricked it four times.
Now - I know the bootloader has flash writing code in it, I wonder, can I get this working without the open heart surgery? 🤔
Show threadIvor HewittAug 25, 2025
damnit missed that originally.... there's *another* flash memory chip on the board that's used to hold the bootloader.
Show threadIvor Hewitt
(yes I've broken my bootloader) 🤦
Aug 25, 2025 at 8:19amWeb