So I was doing some tinkering this weekend with my Panda and thought it would be fun to load FEZopen onto my board.
I read I would need to get the erase firmware file from GHI to get this going but I thought I was smart and had a simple work around to erase the firmware and unlock the chip.
Here is what I did:
The reason the ISP and JTAG are locked is due to the CRP register being set to CRP3 mode. So I firgured this is easy, all I do is use IAP to erase all the flash sectors save for sector 0 which is dubbed the boot sector and is locked from writing using IAP commands.
So I went ahead and prepped sectors 1 - 27 for writing and then erased, and low and behold nothing. The chip is dead. It wasn’t until after I realized my mistake. The CRP register is located at address 0x1FC which is still in sector 0 (The sector you can’t erase using IAP!). So now my secondary bootloader has been blown away (which was my intention), but unfortunately CRP is still enable disallowing me access through ISP or JTAG access.
As far as I understand I have put this chip in an unrecoverable state now, can anyone else comment as to the validity of my assertion? Anyone have an idea of how to get out of this state?
I’m assuming anyone that can help, will know what I am talking about, all the terminology I am using is available in the user manual for the LPC23XX series.