519
CHAPTER 27
µ
PD78F4225 AND
µ
PD78F4225Y PROGRAMMING
User’s Manual U12697EJ3V0UM
27.3.1 Selecting communication mode
Flashpro III writes to flash memory by serial communication. The communication mode is selected from Table
27-3 then writing is performed. The selection of the communication mode has the format shown in Figure 27-2. Each
communication mode is selected by the number of V
PP
pulses shown in Table 27-3.
Table 27-3. Communication Modes
Communication Mode
No. of Channels
Pins Used
Note 1
No. of V
PP
Pulses
3-wire serial I/O
3
SCK0/P27/SCL0
Note 2
0
SO0/P26
SI0/P25/SDA0
Note 2
SCK1/ASCK1/P22
1
SO1/TxD1/P21
SI1/RxD1/P20
SCK2/ASCK2/P72
2
SO2/TxD2/P71
SI2/RxD2/P70
3-wire serial I/O
1
SCK0/P27/SCL0
Note 2
3
(handshake
Note 3
)
SO0/P26
SI0/P25/SDA0
Note 2
P24/BUZ
UART
2
TxD1/SO1/P21
8
RxD1/SI1/P20
TxD2/SO2/P71
9
RxD2/SI2/P70
Notes 1.
Shifting to the flash memory programming mode sets all pins not used for flash memory
programming to the same state as immediately after reset. Therefore, if the external
devices do not acknowledge the port state immediately after reset, handling such as
connecting to V
DD
via a resistor or connecting to V
SS
via a resistor is required.
2.
µ
PD78F4225Y only
3.
Other than I, K standards
Caution Select the communication mode by using the number of V
PP
pulses given in Table
27-3.