D12320VF25V Datasheet, PDF (771/1146 Pages) Renesas Technology Corp – Old Company Name in Catalogs and Other Documents

Section 17 ROM
The difference between the erasing procedures in user program mode and user boot mode depends
on whether the MAT is switched or not as shown in figure 17.74.
MAT switching is enabled by writing a specific value to FMATS. However note that while the
MATs are being switched, the LSI is in an unstable state, e.g. access to a MAT is not allowed until
MAT switching is completed finished, and if an interrupt occurs, from which MAT the interrupt
vector is read from is undetermined. Perform MAT switching in accordance with the description
in section 17.27, Switching between User MAT and User Boot MAT.
Except for MAT switching, the erasing procedure is the same as that in user program mode.
The area that can be executed in the steps of the user procedure program (on-chip RAM, user
MAT, and external space) is shown in section 17.29.3, Procedure Program and Storable Area for
Programming Data.
Rev.7.00 Feb. 14, 2007 page 737 of 1108
REJ09B0089-0700