Pin conflict LCD-Shield dfrobot <-> Arduino Ethernet shield

Hello,

both boards work if they are solo connected to the Arduino Uno. But when I attach the LCD-Display on top of the Arduino ethernet-shield doesnt get a connection.

The pin numbers for the ethernet-shield Digital 2, 10, 11, 12, 13 Analog 0, 1
The pin numbers for the lcd-shield Digital 8, 9 Analog 4, 5, 6, 7

Now I read in thread http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1249783990/2 from Baltasar that on the LCD shield pin 10 is (undocumented) also used.

Is there a go around or modification? Or is another LCD-Board better :wink:

Are you referring to this ethernet following shield?

I didn't see they refer to analog 0 and 1. What exactly do these two pins do on the ethernet shield?

I am working on my Phi-1 shield's revision. The new shield should be compatible with ethernet shield :slight_smile:

Yes, this is the shield that I have bought additionally. I had a look at the schematics, but to be true: this is way beyond what I am able and willing 8) to deal with.

I should have sticked to the standard Arduino shields and not bought a cheap one :0 (Although it looks nice with the 5 buttons.)

As far as I know, the "standard" shields are all those listed under arduino.cc's hardware list. There is no standard or official LCD shield. I guess the Arduino guys left this market open for hobbyists so shields like the one you bought or the one I've made can be sold. But not all shields were created equally or updated often!

Can you reroute your LCD shield to use something other than pin 4 and 10? What is so important on the LCD shield that is using 10? If it's a button, don't push it and it won't bother you. Is there documentation on the LCD shield on the pin usage?

No, as far as I understand Baltasar wrote:

and notice that pin 10 (not documented in the manual) is the backlight led controll, so if you send diferent values of PWM to that pin you can dim the backlight.

So there seems to be no way to avoid circumvent the pin.

liudr:
Are you referring to this ethernet following shield?
http://arduino.cc/en/Main/ArduinoEthernetShield

I didn't see they refer to analog 0 and 1. What exactly do these two pins do on the ethernet shield?

I am working on my Phi-1 shield's revision. The new shield should be compatible with ethernet shield :slight_smile:

The Analog 0 and 1 is used for the SD card reader for Write protect switch and card detect switch, it is described in the following link.
http://shieldlist.org/arduino/ethernet-v5

Thanks. It's good to know. The arduino.cc page didn't say about it.

Finally I found a solution: Cut pin 10 from the LCD. But you can preserve the shield. Have a look at: http://hajos-kontrapunkte.blogspot.com/2011/02/arduino-tower-of-babylon.html

Not bad! Whoever designed the shield has not been tuned to arduino.cc for a while :grin:

LeseLaster:
Finally I found a solution: Cut pin 10 from the LCD. But you can preserve the shield. Have a look at: http://hajos-kontrapunkte.blogspot.com/2011/02/arduino-tower-of-babylon.html

Thank you! This completely solved my problem. I have a similar setup (Arduino Uno + ethernet shield + LCD keypad shield. No card in ethernet SD card slot.) and was getting weird behavior with DHCP. Thanks again!

Worked fine for me also. After connecting the LCD shield, ethernet stop working (static ip). After having bent the pin 10 outwards, everything is working fine.

I believe bend is better than cut, so you can still use it in the future.

Mega 2560
Ethernet Shield with SD card
DFRobot LCD Shield with 5 button.

Hi. I had the same issue with LCD, Ethernet & Mega. I cut pin 4 on the LCD and re-routed this pin, with a jumper wire, to A02. But I still had the problem. Even though the LCD does not use pin 10, I fixed the problem by cutting pin 10 off the LCD board. Pin 10 does not seem to effect the operation of the LCD, but the connection seemed to interfere with the ethernet.

It may be too late to suggest this, but - Go-Between Shield - DEV-11002 - SparkFun Electronics