Additional secuirity bits can not be cleared

[frankzyb]

Hi Andy,
     I tested the writing and reading"Additional secuirity bits"on an LPC935 device by MCB900,which configed with an ICP kit(work with FLASHMAGIS).I find the CWP bit can be set to 1,but can not be clear to 0!Why can do this?
     Thanks!

[Andy Ayre]

To clear the CWP bit:

Go to ISP -> Device Configuration
Click on "Clear Config Protection"

This will only work if you have NOT set the DCCP bit. If you have set the DCCP bit then to clear the CWP bit:

Connect to the device using IAP or a parallel programmer
Send the clear configuration protection IAP command (not sure if this is supported by the ISP to ICP bridge)

See the LPC935 user manual for details.

[frankzyb]

Hi Andy,
    Thanks for your response.Using your solution
Go to ISP -> Device Configuration Click on "Clear Config Protection",I can clear all of the Additional secuirity bits--AWP,CWP and DCCP successfully.
    Thanks!