Renesas M32R/ECU Series User Manual page 833

Appendix 4
(2) Avoiding effects of rapidly level-changing signal lines
Locate signal lines whose levels change rapidly as far away from the oscillator as possible. Also, make sure
the rapidly level-changing signal lines will not intersect the clock-related signal lines and other noise-sensi-
tive signal lines.
<Reasons>
Rapidly level-changing signal lines tend to affect other signal lines as their voltage level frequently rises and
falls. Especially if these signal lines intersect the clock-related signal lines, they will cause the clock waveform
to become distorted, which may result in the microcomputer operating erratically or getting out of control.
Locate the signal line away from the clock-related and other signal lines
Figure 4.13.8 Example Wiring of a Rapidly Level-Changing Signal Line
Signal line intersecting the clock-related and other signal lines
Appendix 4-28
SUMMARY OF PRECAUTIONS
Appendix 4.13 Precautions about Noise
High-speed serial I/O
High-speed timer input/output, etc.
XIN
XOUT
VCNT
High-speed serial I/O
High-speed timer input/output, etc.
XIN
XOUT
VCNT
32180 Group User's Manual (Rev. 1.0)