Hi,
After adding an OTP AES boot to my project (that is based mostly on XR-USB-AUDIO-2.0-MC) I discovered that USB DFU works no longer. Debugging revealed that value of variable that holds DFU mode flag (DFU_reset_override) does not survive during reset.
USB DFU worked fine without OTP AES boot. Apparently OTP AES clears RAM before passing control to firmware in flash.
Has anyone came across such an issue? Is there any idea where else (besides RAM) one could squirrel away a flag indicating DFU mode?
Armands
XS1-L + OTP AES boot + USB DFU
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armands117
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lilltroll
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There is instructions to write/read to the registers in the switch, but I do not know if that solves your problem. There is som registers only used for debugging, so they will not be set by other processes during DFU i guess.
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armands117
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Thanks, good idea! Values in registers of switch should survive restart of individual core. I will try that.lilltroll wrote:There is instructions to write/read to the registers in the switch, but I do not know if that solves your problem. There is som registers only used for debugging, so they will not be set by other processes during DFU i guess.
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armands117
- Member
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- Joined: Fri Dec 28, 2012 1:39 am
Unfortunately experiments revealed that PSwitch registers are wiped during restart so this is not an option.armands117 wrote:Thanks, good idea! Values in registers of switch should survive restart of individual core. I will try that.lilltroll wrote:There is instructions to write/read to the registers in the switch, but I do not know if that solves your problem. There is som registers only used for debugging, so they will not be set by other processes during DFU i guess.