Pages: [1]   Go Down
Author Topic: Multiple LCD's  (Read 1134 times)
0 Members and 1 Guest are viewing this topic.
Albany, NY
Offline Offline
Newbie
*
Karma: 0
Posts: 17
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

I am new to Ardunio, but loving what I see so far.

I just purchased a Uno R3.  I have been messing around with it and I think it is awesome!

I have not ordered any LCD's yet. However, I am looking to display 2 different LCD's, use 2 different temp sensors, and run a couple relays for power outlets.  Will the Arduino be sufficient for this setup?

Thanks.
Logged

Switzerland
Offline Offline
Faraday Member
**
Karma: 108
Posts: 5145
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

If you use I2C LCD displays and DS18B20 temperature sensors you're fine, else you may run out of pins, depending on what "a couple of" is actually in numbers. Standard LCDs with 4-bit parallel interface use at least 6 pins, thermistors use an analog pin, so you need 14 pin out of 20 just for them. Usually you want the serial interface for debugging, make 2 additional pins, leaving 4 for your relays. Is this a couple of?
Logged

Norfolk UK
Offline Offline
Faraday Member
**
Karma: 69
Posts: 2557
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

If you use I2C LCD displays and DS18B20 temperature sensors you're fine, else you may run out of pins, depending on what "a couple of" is actually in numbers. Standard LCDs with 4-bit parallel interface use at least 6 pins, thermistors use an analog pin, so you need 14 pin out of 20 just for them. Usually you want the serial interface for debugging, make 2 additional pins, leaving 4 for your relays. Is this a couple of?
Could you parallel the Data, R & R/W pins to both LCD's and have separate E line for each LCD's. It's not a thing I have tried but data should only get latched when the (E)nable pin is pulsed so should be able to steer the data to the required LCD. This would save 5 pins.
Logged


Offline Offline
Edison Member
*
Karma: 116
Posts: 2205
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Quote
I am looking to display 2 different LCD's, use 2 different temp sensors, and run a couple relays for power outlets.  Will the Arduino be sufficient for this setup?

that would depend on whath kind of LCDs, temp sensors / relays you are talking about. Some of them can take a lot of pins.
Logged

Offline Offline
Newbie
*
Karma: 0
Posts: 7
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Should be enough. 2 x 5 pins for the LCDs and 2 x 1 pin for the temperature sensor.
Logged


Albany, NY
Offline Offline
Newbie
*
Karma: 0
Posts: 17
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

The temp sensors need two pins I believe.... Input and output.... I will link the components I bought when I get home from work
Logged

Leeds, UK
Offline Offline
Edison Member
*
Karma: 80
Posts: 1726
Once the magic blue smoke is released, it won't go back in!
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

If they are standard LCDs that work with the LiquidCrystal library, then they can share the data pins and the R/S pin. Each one simply has its own enable pin which the arduino then uses to select which to talk to. On one arduino uno alone you could have up to 9 such displays, your two temperature sensors and still be able to communicate with the computer.
Logged

~Tom~

Albany, NY
Offline Offline
Newbie
*
Karma: 0
Posts: 17
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

https://www.sparkfun.com/products/11042
http://www.adafruit.com/products/165

I need two of each of these on the Arduino.  And I also need two LCD's, which I have not purchased yet. 
Logged

Central MN, USA
Offline Offline
Tesla Member
***
Karma: 73
Posts: 7197
Phi_prompt, phi_interfaces, phi-2 shields, phi-panels
View Profile
WWW
 Bigger Bigger  Smaller Smaller  Reset Reset

The comments you are receiving are all about character displays. All suggestions are good. You may also use serial displays with addressing capability. My phi-panel LCD backpack has that feature. You only need 1 wire to drive up to 255 displays  smiley-lol smiley-lol

If you want a graphical display, you need to indicate which one.
Logged


Albany, NY
Offline Offline
Newbie
*
Karma: 0
Posts: 17
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Yes everybody's comments are great and helpful.  I said I would list what I bought so I did.

I only need to output text on the LCD's.
Logged

Offline Offline
Edison Member
*
Karma: 116
Posts: 2205
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

Quote
which I have not purchased yet.

It is hard to help you without knowing specifics about the lcds you intend to connect.

In general, there is nothing inherent in arduinos to prevent multiple devices (identical or otherwise) to be connected.
Logged

Albany, NY
Offline Offline
Newbie
*
Karma: 0
Posts: 17
View Profile
 Bigger Bigger  Smaller Smaller  Reset Reset

I'm open to suggestions on the LCD's.
Logged

Pages: [1]   Go Up
Jump to: