MG84FL54BD Datasheet, PDF (28/113 Pages) Megawin Technology Co., Ltd – Four and half configurable I/O ports

Fig 10-1 Quasi-Bidirectional I/O
2 clocks
delay
Port latch data
VDD
VDD
VDD
Strong
Very weak
Weak
Port pin
Input data
10.1.2. Open-Drain Output
The open-drain output configuration turns off all pull-ups and only drives the pull-down transistor of the port pin
when the port register contains a logic “0”. To use this configuration in application, a port pin must have an
external pull-up, typically a resistor tied to VDD. The pull-down for this mode is the same as for the quasi-
bidirectional mode. In addition, the input path of the port pin in this configuration is also the same as quasi-
bidirectional mode.
Fig 10-2 Open-Drain Output
Port latch data
Port pin
Input data
10.1.3. Input-Only (Hi-Z)
The input-only configuration is a Schmitt-triggered input without any pull-up resistors on the pin.
Fig 10-3 Input-Only
Input data
Port pin
10.1.4. Push-Pull Output
The push-pull output configuration has the same pull-down structure as both the open-drain and the quasi-
bidirectional output modes, but provides a continuous strong pull-up when the port register contains a logic “1”.
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MG84FL54B Data Sheet
MEGAWIN