Fujitsu F2MC-8FX Hardware Manual page 563

CHAPTER 29 EXAMPLE OF SERIAL PROGRAMMING CONNECTION
Note:
The pull-up and pull-down resistances in the above example connection are examples only and may
be adjusted to suit your system. If variation in the input level to the MOD pin is possible due to noise
or other factors, it is also recommended that you use a capacitor or other method to minimize noise.
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