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<RESET pin>
If the reset signal of the dedicated flash programmer is connected to the RESET pin connected to the reset signal
generator on-board, a signal conflict occurs. To prevent this, isolate the connection with the reset signal
generator.
If the reset signal is input from the user system in the flash memory programming mode, a normal programming
operation cannot be performed. Therefore, do not input reset signals from other than the dedicated flash
programmer.
µ
PD78F9801
RESET
<Port pins>
When the µ PD78F9801 enters the flash memory programming mode, all the pins other than those that
communicate with flash programmer are in the same status as immediately after reset.
If the external device does not recognize initial statuses such as the output high impedance status, therefore,
connect the external device to V
<Resonator>
When using the on-board clock, connect X1 and X2 as required in the normal operation mode.
When using the clock output of the flash programmer, connect it directly to X1, disconnecting the main resonator
on-board, and leave the X2 pin open.
<Power supply>
To use the power output from the flash programmer, connect the V
programmer, and the V
and V
SS0
To use the on-board power supply, make connections in accordance with the normal operation mode. However,
because the voltage is monitored by the flash programmer, be sure to connect VDD of the flash programmer.
<Other pins>
Process the other pins (USBDP, USBDM, REGC) in the same manner as in the normal operation mode.
CHAPTER 14
Figure 14-7. Signal Conflict (RESET Pin)
Signal conflict
Reset signal generator
The signal output by the reset signal generator and the signal output from
the dedicated flash programmer conflict in the flash memory programming
mode, so isolate the signal of the reset signal generator.
, V
, V
, or V
via a resistor.
DD0
DD1
SS0
SS1
pins to GND of the flash programmer.
SS1
User's Manual U12978EJ3V0UD
µ µ µ µ PD78F9801
Connection pin of
dedicated flash
programmer
Output pin
and V
DD0
DD1
pins to VDD of the flash
197
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