Reading the Factory Information Resistors when device is in hard fault

RE: Reading the Factory Information Resistors when device is in hard fault

MartinBL — Mon, 22 Jan 2018 14:45:51 GMT

Let us continue in the other thread.

RE: Reading the Factory Information Resistors when device is in hard fault

soumil — Sat, 20 Jan 2018 04:34:55 GMT

Thanks RK for your answer. As I mentioned in the other question as well, I am just toggling a GPIO pin and even that is giving a hard fault. Would the approach you mentioned still work in this case?

RE: Reading the Factory Information Resistors when device is in hard fault

Matt — Sat, 20 Jan 2018 01:59:21 GMT

There's one thing you cannot do during the hardfault: to discover the soft truth :)

RE: Reading the Factory Information Resistors when device is in hard fault

RK — Fri, 19 Jan 2018 23:56:24 GMT

You can read anything you like in hardfault. In fact you can execute any code you want totally as long as it doesn't require an interrupt or move to an execution level outside hardfault. You could mine bitcoin from hardfault if you wanted.

So yes you can read the FICR and the UICR and memory and peripherals and any other thing you want.

Your suggestion however that you have a hardfault because of corruption in memory and that even if you did you could debug it by reading the FICR is just fanciful and 99.999999% entirely wrong. If you have a hardfault, use the registers, find the stack, find out where you were executing code and work backwards. There are numerous tutorials for actually debugging hardfaults in ARM processors on the web, it takes work, but it's better than just making unlikely guesses.

RE: Reading the Factory Information Resistors when device is in hard fault

Matt — Fri, 19 Jan 2018 21:25:32 GMT

You meant registers right? Should be do-a-ble, like reading the user/factory info config registers.