RX610 Group
3. Operating Modes
R01UH0032EJ0120 Rev.1.20
Page 88 of 1006
Feb 20, 2013
3.
Operating Modes
3.1
Operating Mode Types and Selection
Operating modes are specified by the MD1 and MD0 pins and the ROME and EXBE bits in the system control register 0
(SYSCR0).
The endian can be selected in each operating mode. Endian is specified by the MDE pin. For details on the endian, see
section 11, Buses.
Note:Do not change the state of pins MDE, MD1, and MD0 while the LSI is working. Do not select any combination
other than those specified in table 3.1.
Table 3.1 Selection of Operating Modes by the Mode Pins
Mode Pin
SYSCR0 Initial State
Operating Mode
On-Chip ROM
*
External Bus
MD1
MD0
ROME
EXBE
0
1
1
0
Boot mode
Enabled
Disabled
1
0
1
0
User boot mode
Enabled
Disabled
1
1
1
0
Single-chip mode
Enabled
Disabled
Note:
*
The on-chip ROM is classified into two flash memories: ROM and data flash. For details, see section 26, ROM
(Flash Memory for Code Storage), and section 27, Data Flash (Flash Memory for Data Storage).
Table 3.2 Selection of Operating Modes by Register Setting
SYSCR0
Operating Mode
On-Chip ROM
*
External Bus
ROME
EXBE
0
0
Single-chip mode, user boot mode
Disabled
Disabled
1
0
Enabled
Disabled
0
1
On-chip ROM disabled extended mode
Disabled
Enabled
1
1
On-chip ROM enabled extended mode
Enabled
Enabled
Note:
*
The on-chip ROM is classified into two flash memories: ROM and data flash. For details, see section 26, ROM
(Flash Memory for Code Storage), and section 27, Data Flash (Flash Memory for Data Storage).
Table 3.3 Selection of Endian
Mode Pin
Endian
MDE
0
Little endian
1
Big endian