
CHAPTER 18
PD78F9418A
User’s Manual U13952EJ3V1UD
263
<RESET pin>
When the reset signal of the dedicated flash programmer is connected to the RESET pin connected to the reset
signal generator on the board, a signal conflict occurs. To prevent this signal conflict, isolate the connection with
the reset signal generator.
If a reset signal is input from the user system in the flash memory programming mode, a normal programming
operation will not be performed. Do not input signals other than reset signals from the dedicated flash programmer
during this period.
Figure 18-7. Signal Conflict (RESET Pin)
RESET
PD78F9418A
Signal conflict
Output pin
Reset signal generator
In the flash memory programming mode, the signal output
by the reset signal generator and the signal output by the
dedicated flash programmer conflict, therefore, isolate the
signal on the reset signal generator side.
Connection pin of dedicated
flash programmer
<Port pins>
Shifting to the flash memory programming mode sets all the pins except those used for flash memory
programming communication to the status immediately after reset.
Therefore, if the external device does not acknowledge an initial status such as the output high impedance
status, connect the external device to VDD0, VDD1, VSS0, or VSS1 via a resistor.
<Oscillation pins>
When using an on-board clock, connection of X1, X2, XT1, and XT2 must conform to the methods in the normal
operation mode.
When using the clock output of the flash programmer, directly connect it to the X1 pin with the on-board main
oscillator disconnected, and leave the X2 pin open. For the subclock, connection conforms to that in the normal
operation mode.
<Power supply>
To use the power output of the flash programmer, connect the VDD0 and VDD1 pins to VDD of the flash
programmer, and the VSS0 and VSS1 pins to GND of the flash programmer.
To use the on-board power supply, connection must conform to that in the normal operation mode. However,
because the voltage is monitored by the flash programmer, therefore, VDD of the flash programmer must be
connected.
For the other power supply pins (AVDD, AVREF, AVSS), supply the same power supply as in the normal operation
mode.
<Other pins>
Handle the other pins (S0 to S15, COM0 to COM3, VLC0 to VLC2, BIAS) in the same way as in the normal
operation mode.