CHAPTER 4 HOW TO USE MINICUBE2 WITH 78K0 MICROCONTROLLER
User’s Manual U18371EJ1V0UM
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4.1.4 Cautions on target system design
Note the following cautions when designing the target system.
• Do not place X1/OCD1A and X2/OCD1B next to each other on the target system. If the layout requires this,
they should be made as short as possible.
• Make the distance between the target connector and the target device as short as possible.
• Since the X1/OCD1A and X2/OCD1B lines are used for clock supply, be sure to shield them, such as with a
GND pattern.
• Before shipping the product, use jumpers or other means to physically separate the X1/OCD1A and X2/OCD1B
pins from the target connector in order to ensure normal clock oscillation.
• When debugging, remove capacitors, feedback resistors, and other elements for the resonator in order to
prevent signal degradation due to the load placed on the X1/OCD1A and X2/OCD1B pins.
Figure 4-19. Reference Diagram of Target System
GND pattern
Target device
X1
X2
Make the pattern where X1 and X2 are
next to each other as short as possible, or
make the space wider
Connect to the connector by using
tin plating when debugging
Shield both sides of the line to
reduce noise
To debug
connector
GND pattern
Target device
X1
X2
Make the pattern where X1 and X2 are
next to each other as short as possible, or
make the space wider
Connect to the connector by using
tin plating when debugging
Shield both sides of the line to
reduce noise
To debug
connector
