SH7059 Datasheet, PDF (735/1042 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer

24. ROM (SH7058S)
24.2.2 Operating Mode
When each mode pin and the FWE pin are set in the reset state and the reset signal is released, the microcomputer enters
each operating mode as shown in figure 24.2. For the setting of each mode pin and the FWE pin, see table 24.1.
• Flash memory cannot be read, programmed, or erased in ROM invalid mode. The programming/erasing interface
registers cannot be written to. When these registers are read, H'00 is always read.
• Flash memory can be read in user mode, but cannot be programmed or erased.
• Flash memory can be read, programmed, or erased on the board only in user program mode, user boot mode, and boot
mode.
• Flash memory can be read, programmed, or erased by means of the PROM programmer in programmer mode.
ROM invalid
mode
RES=0
ROM invalid
mode setting
Reset state
RES=0
Programmer
mode setting
PROM mode
R_U^E_s^S_er⁼_m⁰_ode setting
Boot
RES₌₀
mode _setting
User mode
FWE=0
User program
FWE=1
mode
RAM emulation is enabled
User boot
mode
On-board programming mode
Boot mode
Figure 24.2 Mode Transition of Flash Memory
Table 24.1 Relationship between FWE and MD Pins and Operating Modes
Mode
ROM Invalid ROM Valid User
User Boot
Reset State Mode
Mode
Program
Mode
Boot Mode
Pin
Mode
RES
0
1
1
1
1
1
FWE
0/1
MD0
0/1
0
0/1*¹
0
0/1*²
1
0/1*²
1
0/1*²
1
0/1*²
MD1
0/1
0
1
1
0
0
MD2
0/1
1
1
1
0
1
Notes: 1. MD0 = 0: 8-bit external bus, MD0 = 1: 16-bit external bus
2. MD0 = 0: External bus can be used, MD0 = 1: Single-chip mode (external bus cannot be used)
Program-
mer Mode
1
0/1
1
1
0
Rev.3.00 Mar. 12, 2008 Page 645 of 948
REJ09B0177-0300