turntable

I am working on a project to have a random word guessing game. So far most of the code is working but I am trying to implement some rules on the length of words displayed to the user as a measure of game difficulty (shorter words = easier, etc). I am using a drop-down menu to get the user's setting selection, and then have rules in the JS tags that are supposed to be handling this.

After toying around with this for several days, I was hoping that a fresh pair of eyes might have a suggestion about where I am going wrong to be able to enforce the rules I am trying to enforce?

The specific functions that should be handling this are setDifficulty(), getSelection(), and randomWord()

I need to write a program to control a stepper motor using an atmega328P and an A4988 chip. I've been looking for suitable libaries but so far I haven't been to find a suitable one.

I need a turntable to turn to pre-taught in absolute positions. I thought that the motor in question had 20000 steps per revolution with 1/16th microstepping. When the position counter reaches 20000 it must be set back to 0 and vice versa. So traveling from 19999 to 1 can be done in both directions.

I would like the stepper motor to accelerate and decelerate linear. This is the one thing I do not exactly know how to do this.

I want to use the micros() timer function of the arduino IDE to time the pulses on the step pin.

I can calculate how much pulses I have to travel, and I can increment/decrement speed with a fixed interval but I am having difficulties with calculating when to start decelerating.

If I adjust the speed, after every time I take a step, the acceleration is not linear. I tried to calculate the braking distance with: pulses = VV / 2. Which I derived from basic movement and travel formula. S(t) = S0 + V0 * t - 0.5A*t^2. I take 1 for A and 1 for T. Every time I inc/dec the speed with 1. So I get S(1) = V^2 - 0.5 * V^2 = 0. * V^2 or V^2 / 2.

Incrementing speed is not synchronized with the pulses and I am not sure how to fix this.

I could use some pointers.

Background: The stepper will be controlling a model railway turntable. The turntable will be correctly connected to the axle of the motor. The controller will have 4 buttons.

• manual/automatic button.
• CW
• CCW
• store position

In automatic mode the motor can shift from one taught in position to another position by pressing CW and CCW. It must also be possible to accept a new position when the turntable is still turning.

In manual mode I can use the same CW and CCW buttons to cruise the turntable manually. When I hold a button the motor needs to accelerate to pre-set maximum speed, when I release the button the motor need to decelerator to 0.

With the store button I can save the current position in one of the 20 reserved slots.

The first time that the controller is powered up, it will take the motor's current physical position as a virtual zero point. Every time when the turntable stops, it's current position will be stored in EEPROM. May it be obvious that the turntable won't be move from external force when the controller is turned off.

Edit for the comment + answer

I have already made a simple state machine.

I am not using any library to control the stepper, I currently use the micros() timer to set steps.

All the code between the macros REPEAT_MS and END_REPEAT runs with the given interval in us

I have multiple containers. When pressing 'Play' I want to target the parent audio container to play instead of all the other containers.

Each time I press the play button, all the audio containers fire and start playing. What I want is to target the parent container of the pressed button and only play that container.

I understand that I can use parentNode for this but whenever I implement it, I get an error, whether I use it for the IF argument or the add/removeClass syntax.

I have been researching this over the last week - 2 weeks and I have been unable to find a solution. I am loading a 3D Model from an STL file and attempting to rotate the 3D model automatically around 1 axis. The idea would be something like a slow-moving animation that displays a 360-degree view around the Y-axis of the model.

XAML: