H8S2112R Datasheet, PDF (785/984 Pages) Renesas Technology Corp – 16-Bit Single-Chip Microcomputer H8S Family / H8S/2100 Series

Section 24 Flash Memory
(3) User MAT Erasing in User Boot Mode
For erasing the user MAT in user boot mode, additional processing made by setting FMATS are
required: However, switching back from user-MAT selection state to user-boot-MAT selection
state after programming completes is impossible.
Figure 24.15 shows the procedure for erasing the user MAT in user boot mode.
Start erasing
procedure program
Select on-chip program
to be downloaded and
specify download
destination by FTDAR
Set FKEY to H'A5
Set SCO to 1 and
execute download
Clear FKEY to 0
DPFR = 0?
No
Yes _{Download error processing}
Set the FPEFEQ
parameter
Initialization
JSR FTDAR setting + 32
FPFR = 0?
No
Yes _{Initialization error processing}
1
Set FMATS to value other
MAT
than H'AA to select user MAT _switchover
Set FKEY to H'5A
Set FEBS parameter
Programming
JSR FTDAR setting + 16
FPFR = 0?
No
Yes Clear FKEY and erasing
error processing
No
Required
block erasing is
completed?
Yes
Clear FKEY to 0
Disable interrupts
and bus master operation
other than CPU
End erasing
procedure program
1
Figure 24.15 Procedure for Erasing User MAT in User Boot Mode
Rev. 1.00 May 09, 2008 Page 759 of 954
REJ09B0462-0100