I have a system with an R8C1B up and running except for the Data FLASH.  I have attempted to implement code similar to the app note R01AN0109EJ0100 "R8C/2D Group - Rewriting the Data Flash Using the Suspend Function in EW1 Mode", to no avail.  I had hoped that this was similar enough to the 1B, but, the code seems to be lacking.  I can erase and get a successful status back from the status check, and I get a successful status on a write when I write 0xA5.  However, when I read, I still get 0xFF in stead of 0xA5.  I do not see any means or mention of enabling the Data FLASH, but, it seems that I am missing something.  I have used Data FLASH in the R8CM12, but, that is not similar to the 1B.  

Can anyone offer any advice?  The older links, that might have been useful, in the FAQs section are inactive.


Thank you,


  • Data flash in R8C/1B and R8C/2D look the same. So a code working with 2D should also work with 1B.
  • Hi Lane,

    Have you found a solution ti your issue about this?

    RenesasRulz Forum Moderator

  • In reply to FrankL:

    I am still unable to utilize the data FLASH on my R8C1B. The 2D code is useful, up to a point, but since the 1B does not have an RA timer, it is not a direct code transfer. The documentation, as well as the 2D example code, for the use of the data FLASH in EW1 mode is a bit nebulous in the description of "an interrupt" in the Conditions for transition to erase-suspend/program-suspend. I have a timer "tick" running in my 1B, if any interrupt will do, and I have attempted the commands with suspend enabled and disabled. I have downloaded the 2D code example and it has not shed any light on the issue. The full_sts_chk() always returns a NORMAL operation, but the only value that I have ever read is 0xFF, no matter what I write. Has anyone successfully erased/written/read to the 1D? I would expect so, but have not seen a single example, working or otherwise. Any help would be greatly appreciated.