Firstly, my apologies for using incorrect language etc. I am very new to all this and am trying to learn extremely quickly. I am extremely appreciative of any help that can be offered and thank you for reading on. I have been trying to create a sketch to control a T-Gauge 1/450 scale model railway turntable with simple clockwise and anti clockwise buttons to control direction. I then desire motor travel to the next pre-stored location/step count in said direction. I have been going around and around in circles for a week or more (pun intended) that im getting dizzy. Can i please reach out for some guidance/advice, especially as to whether this project is feasible or not. I have read so many online pages, watched tutorials, followed youtube videos, etc. I have even attempted to use Chat GPT as one video recommended it. All to no success. I then spent time building and wiring a tester board with sensors, switches, buttons, pots, LEDS etc all built in so as to simplify wiring and ensure it was not the wiring at fault. I am satisfied following extensive testing that these are all now wired correctly. I have tried learning about .cpp and .h files to try and break the code down but I think im getting more and more confused. I even attempted to follow some tutorials to enable me to create these but im starting to believe my entire approach is wrong. Please help. I am trying to create the program/sketch to meet my brief as below: i need it to control a stepper motor 28byj- 48 using an uln2003 driver board to be used as a model rail turntable. - I do not require anything too substantial due to the size if the model. i need to be able to store 12 saved locations. 6 locations and then the same 6 plus a half turn so the train can be turned around to face the opposite way. I also require one additional ‘home’ location set at 150 steps clockwise from zero. This should remain locked. This ensures there will always be one saved location from zero. i require the last known position to be stored to the EEPROM for next power up. if power is lost before saving the current location then upon power up the zero routine should be automatically initiated. Upon power up, and if the last position is known, the motor should turn a quarter turn clockwise, followed by a quarter turn counter clockwise, to show the user that the system is ready and calibrated. If the last position is unknown the find Zero Routine will activate automatically. the zero routine should also be able to be activated manually by holding both directional buttons down for 5 seconds. The Zero Routine should allow for the LM393 IR Optocoupler to determine the zero when the beam is broken. - i can use an alternative, a micro switch, a KY-024 hall effect sensor, etc., as per advice and guidance but i am very limited on space due to the size of model. When active this motor should turn counter clockwise until the beam is broken. This beam break is zero location. Whilst this zero routine is active all 4 leds should be lit constantly. Once zero is located the motor should turn clockwise to home and then flash all 4 leds twice to show the user the system is calibrated and ready. The system will then revert back to normal operating mode and await a user input. Normal operating mode should act as follows. i would like to be able to control direction of travel with a push button for clockwise and a different push button for counter clockwise travel. when a button is pressed the motor will move to the next saved position in the desired direction of travel. whilst travelling the corresponding directional led will light to show which direction the motor is in motion to the user. if the directional button is held pressed for 3 or more seconds the motor will complete a half turn in the desired direction. the corresponding directional led will flash until the desired location is met. Whilst a travel order is being carried out a button press in the same direction of travel will be ignored until the destination is reached. If the direction button for the opposite direction is pressed then this will pause all movement. The motor will then await a directional input, and then move to the next saved location in that direction. i need to be able to activate a ‘customise saved location mode’. In this mode the zero and home locations will be ignored for the user and only zero will be used to determine the steps required to store the desired locations. i need to be able to access this ‘customise saved location mode’ by using a rocker switch. Whilst this switch is on the mode is active. When first turned on the motor will immediately find zero in a clockwise direction and then hold position, awaiting user input. At this point the set position led should light and remain lit whilst in this mode. By turning the switch off the mode is exited and anything unsaved is lost. The motor will then return to home. During this mode if a directional button is pressed, then the motor will turn to the next saved location in that direction, if it exists. This will assist with big steps. If no saved position exists then the motor will remain stationary. In this mode the ky-040 rotary encoder will be used to control precision steps manually to allow for fine tuning. The KY-040 button will then be pressed for 5 seconds to save the current position. This will also save a position exactly a half turn from the set position. To confirm a successfully set saved location both directional leds will light and the set position led will flash 5 times. During this time, the motor will move clockwise 100 steps, then 100 steps counter clockwise. i need to be able to activate a ‘delete saved location mode’. In this mode the zero and home locations will be ignored for the user and only zero will be used to determine the steps required to the desired locations. i need to be able to access this ‘delete saved location mode’ by using a rocker switch. Whilst this switch is on the mode is active. When first turned on the motor will immediately find zero counter clockwise and then hold position, awaiting user input. At this point the delete led should light and remain lit whilst in this mode. By turning the switch off the mode is exited and anything unsaved is lost. The motor will then return to home. During this mode if a directional button is pressed, then the motor will turn to the next saved location in that direction, if it exists. This will assist with big steps. If no saved position exists then the motor will remain stationary. In this mode the KY-040 button will then be pressed for 5 seconds to delete the current position. The rotary dial will remain inactive throughout this mode. This will also delete the position exactly a half turn from the selected position. To confirm a successfully deleted saved location both directional leds will light and the delete led will flash 5 times. Whilst in this mode the user needs to hold the rotary encoder button and the reset button together for 10 seconds to complete a ‘full reset’, thereby deleting all user defined saved locations. To confirm the full reset all leds will flash 10 times and the system will then exit the mode and begin the find zero routine. i require an led to show that power is going to the system and that the motor is awaiting its next input. This led should blink when an action is being received, but otherwise should remain in a solid state. To date i have been using the following pin definitions, however, if need be these can be changed if the Arduino Uno R3 is better allocated another way. // Pin definitions #define IN1 2 #define IN2 3 #define IN3 4 #define IN4 5 #define SENSOR_DO_PIN 6 #define POWER_LED 7 #define DIR_0_LED 8 #define DIR_1_LED 9 #define DIR_0_BUTTON 10 #define DIR_1_BUTTON 11 #define CUSTOMISE_SAVED_LOCATION_MODE_SWITCH 12 #define DELETE_SAVED_LOCATION_SWITCH 13 #define ENC_SW A0 #define ENC_DT A1 #define ENC_CLK A2 #define DELETE_LED A3 #define SET_POS_LED A4 Thank you for reading. Am i asking too much of the Arduino Uno? would a different version work? can anyone recommend where i could locate the code/libraries etc that would work for me? Many thanks. Notridge13

[image] Okay, we will let you mark your own paper :slight_smile: In the image below, if no switches are closed, what colour loop runs ? When no switches are pressed, the #2 Blue loop runs over and over . . . . How many times a second does it loop ? We loop every 5ms, therefore 1 / .005 = 200 times per second, not too bad. If we close SetPosSw then close EncoderSw what colour loop starts to run ? When these switches close, we change from the #2 Blue loop to the #3 Red loop. If the switches are held for 5 seconds, what colour loop runs ? At 5 seconds we change from the #3 Red loop to the #4 Pink loop. If the switches were held for only 3 seconds, what colour loop starts to run ? When we let go of a switch at 3 seconds, we change from the #3 Red loop to the #2 Blue loop. When we let go of the of the switches at 7 seconds what colour loop runs ? When we let go at 7 seconds, we change from the #4 Pink loop to, one time only #5 Green loop. When does the black loop run ? The #1 Black loop runs once at power up and then once again every time we get into the #5 Green loop.

[image] notridge13: Can we change this to ensure either the delete or save switches are also pressed. Im concerned my son may inadvertently delete any saved locations by mistake. By having to also or alt. hold one of the other buttons - which i intend to hide the buttons in the layout - this mistake cannot occur. That's a good question for you. Where in the code would you make these changes ? What switch combination do you want before we proceed with going to the default positions ? :thinking:

[image] notridge13: How would the user know what position they are at and which buttons to press etc. if they dint know which end is which. [TurnTable] :thinking: If the table has the red and blue marks as seen in this image: How about when the red end of the table is touching the track you push CW_Sw (maybe put a Red boot on the switch) to go CW 180 degrees, When the the blue mark touches the track, you push CCW_Sw (maybe put a Blue boot on the switch) to go CCW 180 degrees ? [IMG_2920] Or use coloured heat shrink. [SwitchesOne]

[image] notridge13: An alternative could be a third push to make switch called U-Turn if that would assist here? This is very good and you have one GPIO pin available too, A5. :ok_hand: Do you want to add a 180° turnaround switch ?

Laminate this and put it on your wall. Before you start writing code or wiring components for your project. You must follow the plan below. Make a list of all LEDs, switches, sensors, displays, input and output modules, etc. that will be used in your project; don’t forget the kind of Arduino you will use. Gather all datasheets for these components. For each input, describe exactly how that input will affect the code; write this down. For each output, describe exactly how the code will affect the outputs; write this down. Make a proposed schematic showing how you envision things will be connected. Include power supply connections. Never proceed with wiring connections (or asking for help) without this schematic. Make a program flow diagram (a rudimentary flow chart) of all the software modules you envision is needed in the sketch. In this diagram, briefly identify what each module should accomplish. Write out in words, exactly what the modules in #5 are supposed to do; use point form. Update diagrams, schematics, and documentation as your project advances. When you are finished, make sure your code is fully commented. Comments should describe what the line of code is doing; include why we are doing this. Do not just repeat what the code does. - if( currentLocation == destinationLocation ) //is variable currentLocation equal variable destinationLocation. This is a bad comment. :-1: - if( currentLocation == destinationLocation ) //have we moved the stepping motor to the next track ? This is a good comment. :+1: Keep your code neat. For readability, use white space. Place a unique character header just above all important sections, example ===^===. Us the search tool to find this header, this allows quick stepping through the sketch to find these headers. Example: [2024-06-06_20-46-01] [2024-06-06_20-54-16] When you are finished, make sure your schematic is fully up to date.

To make the final control box pretty, look at these links for the bezel. [H] [image] Share tips you have come across General Electronics Making a Reasonable looking Test Jig The following images show how to build a test jig. [A] Design your front panel layout. Print a 1:1 paper copy and add double stick tape. Laminate. [B] [C] [D] [E] [F] [G] Enlarge the holes for your LEDs switches etc. [H] [I] [J] [K] See this post for soldering the proto board components: [A] [image] Share tips you have come across General Electronics Adding a Clear Acrylic Bezel to a Project Box The following images discuss the process for adding a display bezel to a project box/enclosure. The discussion assumes you have access to some tools. We are adding a SSD1306 OLED display to the cover of a Project Box. We use double stick tape to affix a laminated label to the surface of the box cover. There is a cutout in this label for viewing the display. This cutout is smaller than the bezel we are discussing. [A] [B] [C] [D] [E] […

[image] LarryD: What switch combination do you want before we proceed with going to the default positions ? I think the delete switch as we are deleting the user set locations. Do you agree?

[image] LarryD: How about when the red end of the table is touching the track you push CW_Sw (maybe put a Red boot on the switch) to go CW 180 degrees, When the the blue mark touches the track, you push CCW_Sw (maybe put a Blue boot on the switch) to go CCW 180 degrees ? I may not have explained what my thoughts were appropriately. In theory what you say makes perfect sense. However, in real world usage the blue and red wouldn’t be painted on the turntable. And some models don’t have a differentiating item to the user to know which end is which. Some are purely a piece of track, whilst yes, larger ones usually have an area with controls/staff to stand your idea would work great. But for the only track/smaller options the user won’t know which way around the track is to begin with. Another problem that can easily occur is that the user may not even be able to see the turntable - but that really complicates things and I don’t think we needs to go that far as it means building in a form of communication to the users controller where it is situated. So ideally the user would be able to press cw to cw and ccw to go ccw - 180s if held etc. but at present only the main address’s go Cw and the auto address’s only go ccw. Obviously id prefer the user could hold either button and the table simply did a u turn in that direction. But if we can’t go beyond the step count/359 degrees etc then that’s not possible. In the event that this cannot be achieved it could be easier for the end user to push a single button and the turntable auto u turns in the direction it is allowed to move. Like you say, especially as we have a spare place for a switch. What do you think?

Hopefully these pics show what I mean. So on this one the user could know what way around the table is based on the staff control area on the model. [IMG_3098] On this one though the user wouldn’t know which end of the table was which. Once it had been spun a few times etc, whilst also running a layout, it’s unlikely the user would know which end was which. [IMG_3099]

The other point I was trying to make was that if we don’t allow the steps to reset at 360degrees/4096 steps, then the user would have to go the long way around. From say 4048 steps back to 400. I’ve used your picture/diagram to show what I meant. [IMG_3100] If the turntable rotates at a prototypical speed, this could be very slow and to take the yellow route would be a significantly longer time of travel than going the green route, and a lot more user inputs would be required. can we therefore please look at amending the code to allow this to occur? Would doing so then allow both cw and ccw switches to be held for a u turn in either direction no matter where we are situated? This would negate the need for the extra switch. And I think it would be more user friendly in the long run. But I am all ears for your thoughts - at the end of the day I am totally following your lead in what can/cannot be done. Hopefully that all explains what I meant a bit better.

Model Railway Turntable - in a spin so much Im dizzy

Projects General Guidance

LarryD June 7, 2024, 1:33am 465

To make the final control box pretty, look at these links for the bezel.

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Model Railway Turntable - in a spin so much Im dizzy

To make the final control box pretty, look at these links for the bezel.

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