NEC mPD78F0730 Preliminary User's Manual page 459

(1) Signal collision
If the dedicated flash memory programmer (output) is connected to a pin (input) of a serial interface connected to
another device (output), signal collision takes place. To avoid this collision, either isolate the connection with the
other device, or make the other device go into an output high-impedance state.
(2) Malfunction of other device
If the dedicated flash memory programmer (output or input) is connected to a pin (input or output) of a serial
interface connected to another device (input), a signal may be output to the other device, causing the device to
malfunction. To avoid this malfunction, isolate the connection with the other device.
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CHAPTER 19 FLASH MEMORY
Figure 19-9. Signal Collision (Input Pin of Serial Interface)
µ
PD78F0730
Signal collision
Input pin
In the flash memory programming mode, the signal output by the device
collides with the signal sent from the dedicated flash programmer.
Therefore, isolate the signal of the other device.
Figure 19-10. Malfunction of Other Device
µ
PD78F0730
Pin
If the signal output by the PD78F0730 in the flash memory programming
mode affects the other device, isolate the signal of the other device.
µ
PD78F0730
Pin
If the signal output by the dedicated flash programmer in the flash memory
programming mode affects the other device, isolate the signal of the other
device.
Preliminary User's Manual U19014EJ1V0UD
Dedicated flash programmer
connection pin
Other device
Output pin
Dedicated flash programmer
connection pin
Other device
Input pin
µ
Dedicated flash programmer
connection pin
Other device
Input pin
459