"Reading" the Serial 7-Segment Display?

Hi there!

I was wondering if it was possible to read the values from the Serial 7-Segment Display (Using the Serial 7-Segment Display - learn.sparkfun.com).

For instance, if the string "12:34" is displayed, can I "get" that string in the program and set it to a variable?

Thanks!

With a lot of work and many wires, it is possible.
What do you have, and what do you want to achieve ? Perhaps all the work is not necessary.

Peter_n:
With a lot of work and many wires, it is possible.
What do you have, and what do you want to achieve ? Perhaps all the work is not necessary.

I'm using the Serial 7-Segment Display (SparkFun 7-Segment Serial Display - Red - COM-11441 - SparkFun Electronics) and I want to be able to set what's displayed to a variable. (Look at my example in my original post)

What is supposed to have made the "12:34" in the first place?

GoForSmoke:
What is supposed to have made the "12:34" in the first place?

A user entering it in using a 12 digit keypad.

What original post ?
Which device is writing to the Sparkfun display ?
Please give us the minimal information to answer your question.

You (or better saying your Arduino) will send that value to the display, so, you can save that value a know at every time what is it. Don't?

Peter_n:
What original post ?
Which device is writing to the Sparkfun display ?
Please give us the minimal information to answer your question.

I'm using a 12 digit keypad to enter in the numbers. I want to have the PROGRAM read the display and set it to a variable. For example, if the display reads "1234", I want a variable "var" to be set to "1234".

luisilva:
You (or better saying your Arduino) will send that value to the display, so, you can save that value a know at every time what is it. Don't?

Yes, I could, and I might just do that, but I wanted to see if it was possible (and easier) to actually READ the display itself.

It seem to me that what you want is not possible. Check the commands that it can handle:
https://learn.sparkfun.com/tutorials/using-the-serial-7-segment-display/firmware-overview

there’s not a command to "read".

I have a combined display and keypad with 328 board between the two that gives me an idea of what you have.

You possibly could read the states of the LCD pins.

It would be smarter to reprogram the onboard 328 that is already connected and driving the LCD to pass your Arduino the data on command or simply echoed as entered. Just copy the sketch it has first.

The Serial 7-Segment Display can be controlled in one of three ways: Serial TTL communication, SPI serial communication or I2C serial. You can even program it for stand-alone operation since the ATMega328 comes pre-loaded with the Arduino bootloader! There is also an FTDI header on board and we’ve provided a hardware profile for the Arduino IDE to make it even easier to program.

luisilva: but you can make a read command!

If you can and there's enough open pins for your project then why not move your project onto the display 328?

GoForSmoke:
I have a combined display and keypad with 328 board between the two that gives me an idea of what you have.

You possibly could read the states of the LCD pins.

It would be smarter to reprogram the onboard 328 that is already connected and driving the LCD to pass your Arduino the data on command or simply echoed as entered. Just copy the sketch it has first.

The Serial 7-Segment Display can be controlled in one of three ways: Serial TTL communication, SPI serial communication or I2C serial. You can even program it for stand-alone operation since the ATMega328 comes pre-loaded with the Arduino bootloader! There is also an FTDI header on board and we’ve provided a hardware profile for the Arduino IDE to make it even easier to program.

luisilva: but you can make a read command!

If you can and there's enough open pins for your project then why not move your project onto the display 328?

Thanks for the reply, but I think I'm going to go with just saving each value in an array.

Thanks again!

I think I'm going to go with just saving each value in an array.

Huh? What does that have to do with reading the value in the first place?

I get the feeling that you did not understand what I posted at all.

I don't understand either. But now that I reread I think is a good idea. You don't need to read it because you are "inside it".

luisilva:
I don't understand either. But now that I reread I think is a good idea. You don't need to read it because you are "inside it".

On the Sparkfun page are the pictures of the display. On the back is a surface mount 328, what UNO uses but small.
The program on that can be changed, but note there are very few pins available.

I have a different display, an LCD with backpack and keypad from Dr. Liu. Different but also with 328 controller.
On mine, the keypad plugs into the display unit. The user can program the display directly with the keypad.

I look at the Sparkfun 7-segment and wonder how his keypad is connected?

GoForSmoke:

luisilva:
I don't understand either. But now that I reread I think is a good idea. You don't need to read it because you are "inside it".

I look at the Sparkfun 7-segment and wonder how his keypad is connected?

The keypad isn't connected to the 7-Segment. The 7-Segment and the keypad are both connected to DIO ports on an Arduino Mega.

Anyway, this thread is obviously going nowhere. Whether that's my fault of not explaining it clearly (which I feel like I have), I found a way around this.

Thanks for the replies everyone!

jojoguy10:

GoForSmoke:

luisilva:
I don’t understand either. But now that I reread I think is a good idea. You don’t need to read it because you are “inside it”.

I look at the Sparkfun 7-segment and wonder how his keypad is connected?

The keypad isn’t connected to the 7-Segment. The 7-Segment and the keypad are both connected to DIO ports on an Arduino Mega.

Anyway, this thread is obviously going nowhere. Whether that’s my fault of not explaining it clearly (which I feel like I have), I found a way around this.

Thanks for the replies everyone!

Then the keypad is read by the Mega and the Mega is what writes to the display.
Your sketch HAS at some time the information you desire whether you understand that or not.
Save a copy!

It seems that you don't read very well the posts.
What GoForSmoke said is that if you want that functionality you can add it. Why? Because that display is a Arduino UNO with a display attached. And you can do even more! If the display have enough free pins you can do all the application using only the display. (because it's a UNO with an display attached).

But fewer pin connections than an UNO. Enough for TTL RX/TX serial, I2C and SPI.

My Liudr display backpack has 16 pins. The keypad uses 8.
Liudr is a member here but I haven't seen him much lately.

The Sparkfun 7-segment is smaller, flatter and much more compact but I think has fewer free pins.

I have a VS1000 audio module that is also an MCU but not AVR.
A lot of small devices can do more than the design default, by design!

I think that the OP has two language gaps in this thread. One is English, the other is Arduino.
I hope that the OP can hold on until things are more clear for everyone.
What the OP wants to do >>> as stated there is no need. So maybe we find out something more.

Every so often we get a new person who wants to set a pin with Arduino to read on the same Arduino.
So far all of them think they need to do it that way because they did 1 or 2 examples and got ideas.
Ideas are good but be open to more understanding that changes everything.

Has anyone else seen "The Usual Suspects" movie. First time I saw that one, just a few words and suddenly the whole plot changed again and again. Sometimes development is like that, except for the guns and cops.