Hi guys, I am wanting to build a 2 number display for my Grandad's choir so they can see what song to turn to in the book, here is what I have so far:

2 x 7-segment L.E.D display (possibly made from led strips)
Arduino Uno
Infared Remote

The idea is that you can input the song number using some sort of tv remote and then it will appear on the display made from leds.

A few questions:
is an arduino suitable for this?
Will I need any extra components? (possibly infa-red reciever or something)

I am studying mechanical engineering but am still a novice when it comes to programming so any tips will be great. I also preferably want to do this as cheaply as possible.

Thanks in Advance!

 

Why not just text it to their cell phones?

 

Good idea but I don't think it will work for this crowd as they are aged 75+

 

The Arduino is an excellent platform for this.

You can add an IR receiver to the Arduino. It comes with a library of functions to read a remote control. A TV remote is perfect.

Using the IR Receiver libraries, you can read the 2 or 3 digits (representing the hymn) entered on hbd remote.

Then, it’s not too difficult to display those numbers on 7-segment digits. Two digits are pretty easy; 3 digits are more complex or may require an Ardunio Mega.

I’m replying just to answer your question. If you like my idea, I can provide MUCH more information.

 

If you want to use an IR remote, a receiver will be needed.
Addressable WS2812B LED strips can make it easier to drive, so they may be worth a look.

 

Well, since I am 75+, I probably don't have any ideas worthwhile. But, yes, an Arduino can do that, but so can a lot of other devices. RF may be a better choice than IR.

1) How big is the choir? How wide are they placed?
2) What is the setting? At the Mormon tabernacle in SLC?
3) Is there an area that is visible to the choir but not the audience?
4) Do they rehearse a set for each service?
5) How does a philharmonic orchestra know what tunes to play?
6) Will hand or voice signals work?
7) Sounds like a gold shovel without a handle.

 

have a look here
https://learn.adafruit.com/ninja-timer-giant-7-segment-display/overview

 

Ok, if it’s the Mormon Tabernacle Choir...

But most church choirs I’m aware of are within range of a TV remote.

We tend to overthink our answers to a TS. In many cases, the straightforward answer is all we need.

In this case, I envision a choir director within 100 feet of a display, upon which he needs to communicate and display two digits. That’s 5o feet and 2 digits. Nothing requiring a theoretical physics degree.

 

Two 7-segment digits require 14 output pins before it gets complicated. 8 pins with external circuitry. I’ve built giant (18”) 7-segment digits. With logic level MOSFETs driven by a BCD to 7-segment decoder it’s fairly simple, as each digit only needs 4 pins to output.

 

The choir is about 20 people and the idea is that my Grandad will punch in the numbers just before each song starts. Nothing on a large scale, maybe 20 feet away max. The numbers are meant for the audience so they can join in if they wish.

Will I be able to use the output pins on the Arduino directly to the l.e.d.s? or will I need some sort of breakout board? (apologies if the terminology is wrong).

(Thanks Dendad for the link!)

 

Ok, if it’s the Mormon Tabernacle Choir...

But most church choirs I’m aware of are within range of a TV remote.

Most choirs rehearse a small set before service. Hand signals should be sufficient if a number is skipped and the choir is paying attention.

We tend to overthink our answers to a TS. In many cases, the straightforward answer is all we need.

A 75+ individual can't overthink anything -- at least that seems to be the TS's position,

In this case, I envision a choir director within 100 feet of a display, upon which he needs to communicate and display two digits. That’s 5o feet and 2 digits. Nothing requiring a theoretical physics degree.

100 feet? The last time I was in a place of worship with the choir behind the preacher/rabbi, the distance was much smaller than that. When the choir is on a balcony behind and above the parishioners, they are not generally visible and hand signals should work.

I am not saying it can't be done. It can be done easily. But does the grandfather (and choir) want that? #1 rule: find out what the "customer" wants.

 

If you want to drive more than a couple of LEDs per pin, you will need to use a FET or transistor as the Arduino pins can only supply limited current.
Another option in stead of the addressable LEDs would be to drive an MCP23017 16 port bus expander with each port pin driving a FET. Then you can have up to 16 LED strips. That will give up to 199 as a number.

This may have some info. I've not looked into the article in datail...
https://www.instructables.com/id/I2C-Controlled-7-Segment-LED-Display/

 

I would go the WS2812B way. One output to drive both digits, no multiplexing required, simple code, make the digits as big as you want.

Bob

 

The choir is about 20 people and the idea is that my Grandad will punch in the numbers just before each song starts. Nothing on a large scale, maybe 20 feet away max. The numbers are meant for the audience so they can join in if they wish.

Will I be able to use the output pins on the Arduino directly to the l.e.d.s? or will I need some sort of breakout board? (apologies if the terminology is wrong).

(Thanks Dendad for the link!)

I picked 100 feet as a reasonable distance for IR transmission from the conductor to the Arduino. Anything less is gravy. 20 feet is nothing.

Whether you drive the segments directly from the Arduino or a BCD to 7-segment driver, you’ll need drivers. Depending on what you mean by “breakout board”, it’s likely that something will be needed. I used a mosfet per segment, with a pull-down resistor. Nothing complicated.

One IC is the BCD to 7-segment decider driver. A 7447 or 4511 chip does the job. Then the Arduino outputs with four pins each, the BCD value of the digit. This way, you need 8 pins.

If you were to multiplex 2 digits, you’d need 7 pins for the segments plus 1 pin to multiplex two digits. Eight pins. Same as outputting BCD directly.

Not multiplexing is easier and you can not multiplex with the same number of pins. So directly drive each digit with a BCD to 7-segment decoder/driver chip.

 

I think you meant 7447, not 4774.

 

I think you meant 7447, not 4774.

Yes, I did! Original post edited

Dyslexia is a horrible burden.

 

Most hymn books I have seen go past 100 songs. You will need three digits.

I would go with a TV remote IR controller.
The receiver is simple to build using any MCU if you know how to program one.
If you don't we can show you how to do that.