m37905 Renesas Electronics Corporation., m37905 Datasheet - Page 408

• Manufacturer Part Number: m37905
• Description: Mitsubishi 16-bit Single-chip Microcomputer 7700 Family / 7900 Series
• Manufacturer: Renesas Electronics Corporation.

Fig. 19.1.2 Memory assignment of internal flash memory
In addition to the internal flash memory area (in other words, user ROM area) shown in Figure 19.1.1, the
flash memory version has the boot ROM area of 8 Kbytes.
Figure 19.1.2 shows the memory assignment of the internal flash memory.
The user ROM area is divided into several blocks. The user ROM area is reprogrammed in the flash
memory CPU reprogramming mode, serial I/O mode, and parallel I/O mode.
The boot ROM area is assigned at addresses, overlapping with the user ROM area, however, the boot
ROM area exists in the defferent memory; the boot ROM area can be reprogrammed only in the flash
memory parallel I/O mode. (Refer to section “19.4 Flash memory parallel I/O mode.”). When being reset
with pin MD1 tied to Vcc level and pin MD0 to Vss level, the software in the boot ROM area is executed
after reset. (Refer to section “19.1.3 Boot mode.”) When pin MD1 = Vss level, however, the contents of
the boot ROM area cannot be read out.
DFFF
BFFF
FFFF
7FFF
C000
E000
1000
8000
16
16
16
16
16
16
16
16
Note: Addresses FF90
User ROM area
M37905F8
28 Kbytes
16 Kbytes
8 Kbytes
8 Kbytes
Be sure not to use this area.
(Note)
16
to FF9F
7905 Group User’s Manual Rev.1.0
16
are reserved for serial and parallel programmers.
(In boot mode)
FFFF
E000
FLASH MEMORY VERSION
16
16
Boot ROM area
8 Kbytes
(In flash memory parallel I/O mode)
1FFF
0
16
16
19.1 Overview
19-5