CPU frequency error

Question

Hi, 
 
 There was power fluctuation when we were flashing the production board which has RH850 controller. 
 We tried flashing the board again and from then on, we are getting the following error. 
 
 Is there a way to recover from this error? Can you please helo? 
 Thanks and regards, 
 Subasree Venkatesan

Thorsten Kreye (Renesas) · Answer

Dear Subasree Venkatesan, 
 the screen shot show that you are using a RH850/P1x-C. It seems that a "Chip erase" was executed which erases also the default Option Byte settings.(A block erase over all block would NOT erase the Option Bytes.). After such a "Chip erase, it is necessary to set the Option Bytes immediately to valid values. If there is a power fluctuation or any other reset during this flow, the Option Bytes may enter an invalid setting. 
 This is a disadvntage of RH850/P1x.C serie: Invalid Option Bytes (all 0xffffffff) are a setting, which set the internal clock to a configuration, which is invalid and fail. So, the device try to start with an invalid clock setting and fail. This is not recoverable. The device should be de-soldered and replaced by a new one with valid Option Byte settings (e.g. default values). 
 Even Renesas has no chance to recover these Option Bytes by usual tools like Programmer or Debugger, as the device is now incapable to start with a valid clock setting. 
 Best regards