Functions To Prevent Flash Memory From Rewriting - Renesas M16C Series Hardware Manual

R8C/11 Group

17.3 Functions To Prevent Flash Memory from Rewriting

To prevent the flash memory from being read or rewritten easily, standard serial I/O mode has an ID code
check function.
17.3.1 ID Code Check Function
Use this function in standard serial I/O mode. Unless the flash memory is blank, the ID codes sent
from the programmer and the ID codes written in the flash memory are compared to see if they match.
If the ID codes do not match, the commands sent from the programmer are not accepted. The ID code
consists of 8-bit data, the areas of which, beginning with the first byte, are 00FFDF
00FFEB , 00FFEF
16
codes are preset at these addresses and write it in the flash memory.
Figure 17.2 Address for ID Code Stored
Rev.1.20 Jan 27, 2006
REJ09B0062-0120
, 00FFF3 , 00FFF7
16 16
Address
0 0 F F D F t o 0 0 F F D C
1 6 1 6
0 0 F F E 3 t o 0 0 F F E 0
1 6 1 6
00FFE7 to 00FFE4
16 16
0 0 F F E B t o 0 0 F F E 8
1 6 1 6
00FFEF to 00FFEC
16 16
0 0 F F F 3 t o 0 0 F F F 0
1 6 1 6
0 0 F F F 7 t o 0 0 F F F 4
1 6 1 6
00FFFB to 00FFF8
16 16
0 0 F F F F t o 0 0 F F F C
1 6 1 6
N O T E S :
1 . W h e n w r i t e t o a d d r e s s 0 0 F F F F
page 166 of 204
17.3 Functions To Prevent Flash Memory from Rewriting 17.3 Functions To Prevent Flash Memory from Rewriting
, and 00FFFB . Prepare a program in which the ID
16 16
Undefined instruction vector
ID1
ID2 Overflow vector
BRK instruction vector
ID3 Address match vector
ID4 Single step vector
Oscillation stop detection/Watchdog
ID5
timer vector/ voltage detection
ID6 (Reserved)
( R e s e r v e d )
ID7
Reset vector
(Note 1)
4 bytes
, w r i t e " F F
1 6 1 6
, 00FFE3
16
" .
,
16