Windicator
Two TTL ICs and a handful of other components are all that is needed for a circuit that will indicate which of four buttons was pressed first, as well as lock out all other entries. A logic 0 at one of the Q outputs lights the appropriate LED and locks out other entries by taking the clock input low.
The described circuit utilizes two TTL (Transistor-Transistor Logic) integrated circuits (ICs) along with a minimal selection of passive components to create a button press detection system. This system is designed to identify which of four buttons is pressed first and subsequently disable further button presses until the current state is reset.
The primary components involved in this circuit include two 74HC74 dual D flip-flops, which serve to latch the state of the button presses. The four buttons are connected to the data inputs of the flip-flops. When a button is pressed, it generates a logic high signal that is captured by the flip-flops. The first button pressed will set one of the flip-flops to a logic 0 at its Q output, indicating the active button.
To provide visual feedback, each Q output is connected to a corresponding LED. When a button is pressed, the associated LED lights up, providing immediate indication of which button was activated first. The circuit is designed to lock out further button presses by pulling the clock input of the flip-flops low, effectively preventing any additional state changes until the circuit is reset.
Additional components, such as resistors and capacitors, may be used for debouncing the button inputs and ensuring stable operation. A reset mechanism, possibly involving a manual switch or an automatic reset after a certain time, can be incorporated to clear the state of the flip-flops and allow new button presses to be registered.
This circuit exemplifies a simple yet effective use of TTL logic to manage multiple inputs and provide clear output indications while ensuring that only the first input is acknowledged, thus preventing erroneous multiple entries.Two TTL ICs and a handful of other components are all that is needed for a circuit that will indicate which of four buttons was pressed first, as well as lock out all other entries A logic 0 at one of the Q outputs, lights the appropriate LED and locks out other entries by taking the clock input low.
The described circuit utilizes two TTL (Transistor-Transistor Logic) integrated circuits (ICs) along with a minimal selection of passive components to create a button press detection system. This system is designed to identify which of four buttons is pressed first and subsequently disable further button presses until the current state is reset.
The primary components involved in this circuit include two 74HC74 dual D flip-flops, which serve to latch the state of the button presses. The four buttons are connected to the data inputs of the flip-flops. When a button is pressed, it generates a logic high signal that is captured by the flip-flops. The first button pressed will set one of the flip-flops to a logic 0 at its Q output, indicating the active button.
To provide visual feedback, each Q output is connected to a corresponding LED. When a button is pressed, the associated LED lights up, providing immediate indication of which button was activated first. The circuit is designed to lock out further button presses by pulling the clock input of the flip-flops low, effectively preventing any additional state changes until the circuit is reset.
Additional components, such as resistors and capacitors, may be used for debouncing the button inputs and ensuring stable operation. A reset mechanism, possibly involving a manual switch or an automatic reset after a certain time, can be incorporated to clear the state of the flip-flops and allow new button presses to be registered.
This circuit exemplifies a simple yet effective use of TTL logic to manage multiple inputs and provide clear output indications while ensuring that only the first input is acknowledged, thus preventing erroneous multiple entries.Two TTL ICs and a handful of other components are all that is needed for a circuit that will indicate which of four buttons was pressed first, as well as lock out all other entries A logic 0 at one of the Q outputs, lights the appropriate LED and locks out other entries by taking the clock input low.