In SX Microcontrollers, SX/B Compiler and SX-Key Tool, g_daubach wrote:

Some words about the resistor connecting /MCLR to Vdd:

For regular operation, the /MCLR pin must "see" high level, i.e. Vdd. Under normal condition, it would not do any harm to an SX when you tie the /MCLR pin directly to Vdd potential.

The SX inputs are protected against ESD to a certain extend by internal clamping diodes which start conducting when the voltage between a pin and Vss exceeds about 7 Volts. A resistor in series with an input limits the current through the diode, and thus protects the diode. The value of this resistor is not critical. As the inputs have high impedance, they almost sink any current under normal conditions, so the voltage drop across the resistor can be ignored. 10kOhm, or even higher is a good value. Values below 4.7 kOhm my not offer enough protection for the diodes.

In your case, it is absolutely not necessary to use "distributed" pull-up resistors. One resistor attached to all /MCLR pins on one end is just fine.

BTW: With a reset button, as shown in your schematic, the resistor not only functions as current limiter for the diodes but it also limits the current through the reset contact when it is closed.

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