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CHAPTER 25 FLASH MEMORY
User’s Manual U19780EJ2V0UD
595
25.5.2 Serial interface pins
The pins used by each serial interface are listed below.
Table 25-3. Pins Used by Each Serial Interface
Serial Interface
Pins Used
CSI10
SO10, SI10, SCK10
UART6 TxD6,
RxD6
Caution: Only the P60/SCLA0/SCK10 and P61/SDAA0/SI10 pins (when used as the CSI10 pins SCK10 and
SI10) can be used for communicating with the dedicated flash memory programmer. The
P31/INTP5/OCD1A(/SCK10) and P32/INTP4/OCD1B(/SI10) pins cannot be used for communicating
with the dedicated flash memory programmer.
To connect the dedicated flash memory programmer to the pins of a serial interface that is connected to another
device on the board, care must be exercised so that signals do not collide or that the other device does not
malfunction.
(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.
Figure 25-6. Signal Collision (Input Pin of Serial Interface)
Input pin
Signal collision
Dedicated flash
memory
programmer connection pin
Other device
Output 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.
microcontrollers
(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.