A straightforward six-step process begins with Step 1, where the system is in a rest state, awaiting user input. To advance from Step 1 to Step 2, the user must press the correct button. If an incorrect button is pressed, the system returns to Step 1. This pattern continues for Steps 2 through 6. Upon successful completion of Step 6 by the operator, the output will be activated.
The transition from Step 1 to Step 2 is successfully initiated by pressing the correct button. Dear Steve, could you please provide me with a diagram illustrating this step? Thank you!
I'm not able to complete your homework for you. However, I have provided you with a structured outline to help guide you in tackling the assignment. It’s your turn to take the initiative from here.
Haha, don't worry about doing any homework, dear Steve! I'm just starting out in programming. Will I need to use a counter, timer, or an array for this project?
How to Create a State Machine for a 5-Digit Code
Are you looking to draw a state machine for a specific 5-digit code? Let’s explore how many states you can encounter during this process, ranging from 0 correct digits to 5 correct digits. In each of these states, it’s crucial to identify which input combinations will enable you to either progress to the next state or revert back to the initial state.
Once your state transitions are defined, you'll need to determine how to implement a flag that indicates your current state. A recommended approach is to assign a constant value to a Data Integer (DINT) variable named `CurrentState`. Furthermore, it’s essential to establish clear criteria for when this flag should be updated.
By following these steps, you will effectively create a functional state machine for managing your 5-digit code!
Greetings and welcome to the forum! I'm excited to share my journey with you. Although I don't have formal training or an academic background in PLC programming, I've dedicated countless hours to mastering Allen-Bradley (A-B) systems through self-study and practical experience. My goal has always been to create efficient and professional logic solutions that are easy for customers to understand, as highlighted in various discussions here.
I want to emphasize that I won’t be completing your homework for you. Learning from your own experience is essential. However, I can provide some hints to help you with your project involving the button sequence (1-5-3-4-2). Here are some clues to guide your thinking:
1. I built the logic without using arrays, timers, or counters—relying solely on XIC (Examine If Closed), XIO (Examine If Open), and OTE (Output Energize) instructions.
2. The entire sequence was accomplished in just six rungs.
3. I have a PLC and a rack set up in my office, and I’ve tested this logic successfully.
Additionally, remember the concepts of latching or holding circuits that you learned in school; this will be crucial for solving the problem. Stay persistent! The seasoned professionals in this forum are eager to assist you, but it’s important that you make the initial effort. Even incorrect logic can teach you valuable lessons about what to avoid. Welcome once again to the forum, and I look forward to your contributions!
Will your solution function properly with the input sequence 1-1-3-1-1?
The sequence is flexible and can accommodate any requested pattern, such as 1-2-2-3-4.
You can implement a step sequence without the need for timers or counters. Utilize conditions to ensure that the set point activates only when the "1" button is pressed. Next, incorporate a second condition within that step program and continue to build on it. While repeating a number might pose a challenge, counters can assist you in managing that issue effectively. Focus on this approach, noting that each program corresponds to a specific code; if you wish to change the code, you'll need to revise the entire program. There are more efficient solutions available, but I recommend trying this method first for optimal results.
- 30-03-2025
- SagittarianPLC
I struggled to manage the incorrect sequence, while programming the correct sequence was straightforward.
Explore the program outlined in the link I shared earlier, which showcases how to create, input, and compare correct and incorrect sequences effectively. You can find detailed information here: http://accautomation.ca/building-a-plc-program-that-you-can-be-proud-of-part-5/. Additionally, check out this video demonstrating the program's functionalities: https://www.youtube.com/watch?v=QrfnDHCeJjk.
Best regards,