Datasheet

Section 17 Flash Memory (F-ZTAT Version)
Rev.7.00 Dec. 24, 2008 Page 555 of 698
REJ09B0074-0700
17.2 Mode Transitions
When the mode pins and the FWE pin are set in the reset state and a reset-start is executed, this
LSI enters an operating mode as shown in figure 17.2. In user mode, flash memory can be read but
not programmed or erased. The boot and user program modes are provided as modes to write and
erase the flash memory.
The differences between boot mode and user program mode are shown in table 17.1. Boot mode
and user program mode operations are shown in figures 17.3 and 17.4, respectively.
SCI, USB
boot mode
On-board programming mode
User
program mode
User mode
(on-chip ROM
enabled)
Reset state
Programmer
mode
RES = 0
FWE = 1 FWE = 0
*
1
*
1
*
2
Notes: Only make a transition between user mode and user program mode when the CPU is
not accessing the flash memory.
1. RAM emulation possible
2. MD2 to MD0 = 000, PF3, PF0, P16, P14 = 1100
RES = 0
MD2 to 0 = 01x,
FWE = 1
RES = 0
RES = 0
MD2 to 0 = 11x,
FWE = 0
MD2 to 0 = 11x,
FWE = 1
Figure 17.2 Flash Memory State Transitions
Table 17.1 Differences between Boot Mode and User Program Mode
SCI, USB Boot Mode User Program Mode User Mode
Total erase Yes Yes No
Block erase No Yes No
Programming control
program*
Program/program-verify Erase/erase-verify
Program/program-verify
Emulation
—
Note: * To be provided by the user, in accordance with the recommended algorithm.