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Chapter 5 Port Functions
5

Fig. 5-32 Connection of Pull-Up Resistors (Port 5)

5.6.5 Driving LEDs Directly

For port 5, the low level side of the output buffer has an enhanced driving capacity so that it can drive an LED directly

on an active-low signal. Fig. 5-33 is an example of such an output buffer.

Fig. 5-33 Example of Driving an LED Directly

PD78214
µ
VDD
P5n
(n = 0 to 7)
Internal bus
VDD
P50
P51
P52
P56
P57
Input buffer
PUO5
(PUO)
•••
•••
•••
•••
Port 5 mode
register (PM5)