USB JTAG  

Go Back   USB JTAG > USBJTAG (NT) > Product Support.

Reply
 
Thread Tools Display Modes
  #1  
Old 09-23-2017, 03:39 PM
Teddy Boom Teddy Boom is offline
Junior Member
 
Join Date: Jun 2012
Posts: 14
Default Write protection on SPI flash?

Working on some VDSL modems. Whenever I write the full dump from one particular model to an SPI flash, the chip can no longer be erased/written. I am holding both HOLD# and WP# high.

Doesn't matter if the chip is in system or loose on my desk. Tested with the stock flash from the device, of course. I've also written the dump to an MX25L128, but once written, that chip can't be written to again either.
(technically, written, soldered into PCB and run once, then desoldered--that might matter I guess )

I did a tiny bit of reading about the status register on SPI flash, but I'm not seeing the key bit of info..

Am I doing something wrong? Maybe I can edit the hex file to remove this apparent write protection?
Reply With Quote
  #2  
Old 09-23-2017, 06:13 PM
usbbdm usbbdm is offline
Administrator
 
Join Date: Jul 2005
Posts: 8,879
Default

Quote:
Originally Posted by Teddy Boom View Post
Working on some VDSL modems. Whenever I write the full dump from one particular model to an SPI flash, the chip can no longer be erased/written. I am holding both HOLD# and WP# high.

Doesn't matter if the chip is in system or loose on my desk. Tested with the stock flash from the device, of course. I've also written the dump to an MX25L128, but once written, that chip can't be written to again either.
(technically, written, soldered into PCB and run once, then desoldered--that might matter I guess )

I did a tiny bit of reading about the status register on SPI flash, but I'm not seeing the key bit of info..

Am I doing something wrong? Maybe I can edit the hex file to remove this apparent write protection?
I am not aware of a lock feature. If the flash can be read, then it should be able to write with proper setup. Unless for special chip, unlock command is available and needs to be used.
Reply With Quote
  #3  
Old 09-24-2017, 03:57 PM
Teddy Boom Teddy Boom is offline
Junior Member
 
Join Date: Jun 2012
Posts: 14
Default

Quote:
Originally Posted by usbbdm View Post
I am not aware of a lock feature. If the flash can be read, then it should be able to write with proper setup. Unless for special chip, unlock command is available and needs to be used.
Thanks, I'll give it another try.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump


All times are GMT -7. The time now is 12:40 AM.


Powered by vBulletin® Version 3.7.3
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.