Clearing flash protection on STR710

Development Boards MicroMod
1

I have an older STR710 board that I can’t seem to write to the internal flash on. Here’s what OpenOCD 0.1.0 says:

> reset halt
JTAG tap: str710.cpu tap/device found: 0x3f0f0f0f (Manufacturer: 0x787, Part: 0xf0f0, Version: 0x3)
JTAG Tap/device matched
srst pulls trst - can not reset into halted mode. Issuing halt after reset.
target state: halted
target halted in ARM state due to debug-request, current mode: Supervisor
cpsr: 0x500000d3 pc: 0x00070dbc

> flash info 0 
#0: str7x at 0x40000000, size 0x00040000, buswidth 0, chipwidth 0
	#  0: 0x00000000 (0x2000 8kB) protected
	#  1: 0x00002000 (0x2000 8kB) protected
	#  2: 0x00004000 (0x2000 8kB) protected
	#  3: 0x00006000 (0x2000 8kB) protected
	#  4: 0x00008000 (0x8000 32kB) protected
	#  5: 0x00010000 (0x10000 64kB) protected
	#  6: 0x00020000 (0x10000 64kB) protected
	#  7: 0x00030000 (0x10000 64kB) protected
str7x flash driver info

> flash protect 0 0 7 off
cleared protection for sectors 0 through 7 on flash bank 0

> flash info 0           
#0: str7x at 0x40000000, size 0x00040000, buswidth 0, chipwidth 0
	#  0: 0x00000000 (0x2000 8kB) protected
	#  1: 0x00002000 (0x2000 8kB) protected
	#  2: 0x00004000 (0x2000 8kB) protected
	#  3: 0x00006000 (0x2000 8kB) protected
	#  4: 0x00008000 (0x8000 32kB) protected
	#  5: 0x00010000 (0x10000 64kB) protected
	#  6: 0x00020000 (0x10000 64kB) protected
	#  7: 0x00030000 (0x10000 64kB) protected
str7x flash driver info

> flash write_image erase image 0 elf
auto erase enabled
Could not probe bank
auto_probe failed -900

Could not probe bank
auto_probe failed -900

wrote 0 byte from file image in 0.136092s (0.000000 kb/s)

>

I also can’t write the external flash, an SST 16VF160, which seems to be CFI 1Mx16 according to some info I found online. Here’s the flash bank config I use. Any thoughts?

flash bank str7x 0x40000000 0x00040000 0 0 0 STR71x
flash bank str7x 0x400C0000 0x00004000 0 0 0 STR71x

flash bank cfi 0x60000000 0x200000 2 2 0

It doesn’t even recognize the external flash (flash probe/info just says it’s not there).

2

I got the internal flash to work by manually clearing the permanent debug protect. I wrote 0xfffffffe into flash address 0x4010dfbc (NVPROT), by manually twiddling the FCR/FAR/FDR regs to write to that flash address. I then reset, disabled the CFI flash bank config and wrote my image to 0x40000000. ‘flash info’ still says it’s protected though, but maybe this is just temporary protection.

3

you will need to call flash protect_check 0 before the str7 protection info is valid.

eg.

flash protect_check 0
flash info 0

The str7 does not support autoprobe - so would guess the cfi flash is failing.

Also to program using a elf just use:

flash write_image erase image

If you still have problems attach a full debug log.

Cheers

Spen