NEC PD78P214 Manuale Utente

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