3858 Group
MEMORY
ROM Code Protect Address (address FFDB16)
Address FFDB16, which is the reserved ROM area of QzROM, is
the ROM code protect address. "0016" is written into this address
when selecting the protect bit write by using a serial programmer
or selecting protect enabled for writing shipment by Renesas
Technology corp.. When "0016" is set to the ROM code protect ad-
dress, the protect function is enabled, so that reading or writing
from/to QzROM is disabled by a serial programmer.
Special Function Register (SFR) Area
The Special Function Register area in the zero page contains
control registers such as I/O ports and timers.
RAM
RAM is used for data storage and for stack area of subroutine
calls and interrupts.
As for the QzROM product in blank, the ROM code is protected by
selecting the protect bit write at ROM writing with a serial pro-
grammer.
ROM
The first 128 bytes and the last 2 bytes of ROM are reserved for
device testing and the rest is user area for storing programs.
As for the QzROM product shipped after writing, "0016" (protect
enabled) or "FF16" (protect disabled) is written into the ROM code
protect address when Renesas Technology corp. performs writing.
The writing of “0016” or “FF16” can be selected as ROM option
setup (“MASK option” written in the mask file converter) when or-
dering.
Interrupt Vector Area
The interrupt vector area contains reset and interrupt vectors.
Zero Page
Access to this area with only 2 bytes is possible in the zero page
addressing mode.
■ Notes
Special Page
Because the contents of RAM are indefinite at reset, set initial val-
Access to this area with only 2 bytes is possible in the special
ues before using.
page addressing mode.
RAM area
Address
XXXX16
RAM size
(bytes)
000016
SFR area
192
256
384
512
640
768
896
1024
1536
2048
00FF16
013F16
01BF16
023F16
02BF16
033F16
03BF16
043F16
063F16
083F16
Zero page
004016
010016
RAM
XXXX16
Not used
YYYY16
ROM area
Reserved ROM area
(128 bytes)
Address
YYYY16
Address
ZZZZ16
ROM size
(bytes)
ZZZZ16
FF0016
4096
8192
F00016
E00016
D00016
C00016
B00016
A00016
900016
800016
700016
600016
500016
400016
300016
200016
100016
F08016
E08016
D08016
C08016
B08016
A08016
908016
808016
708016
608016
508016
408016
308016
208016
108016
12288
16384
20480
24576
28672
32768
36864
40960
45056
49152
53248
57344
61440
ROM
FFDB16
Reserved ROM area
(ROM code protect address)
Special page
FFDC16
Interrupt vector area
FFFE16
Reserved ROM area
FFFF16
Fig. 8 Memory map diagram
Rev.1.10 Apr 3, 2006 page 10 of 75
REJ03B0139-0110
RENESAS [ RENESAS TECHNOLOGY CORP ]
