# Coding help? vfd to LCD or OLED **URL:** \ **Category:** Displays\ **Created:** [July 19, 2021, 7:30pm UTC](https://forum.arduino.cc/t/coding-help-vfd-to-lcd-or-oled/886919 "2021-07-19T19:30:08Z")\ **Posts on this page:** 1\ **Showing post:** 2
**Author:** ![PerryBebbington](https://dub1.discourse-cdn.com/arduino/user_avatar/forum.arduino.cc/perrybebbington/32/238766_2.png) [@PerryBebbington](https://forum.arduino.cc/u/PerryBebbington)\ **Post date:** [July 21, 2021, 6:41am UTC](https://forum.arduino.cc/t/coding-help-vfd-to-lcd-or-oled/886919/2 "2021-07-21T06:41:06Z")
Hello @anon62867724 Please read [How to get the best out of this forum](https://forum.arduino.cc/t/how-to-get-the-best-out-of-this-forum/679966) Please post your code here in code tags as per the instructions in that tutorial. Some photos would probably be helpful so people can see what you are working with. Have you connected the grounds between the sampler and the Uno? > [@Common ground and why you need one](https://forum.arduino.cc/t/common-ground-and-why-you-need-one/626215): > > A common mistake for people new to electronics is to have 2 circuits fed from different power supplies with signals passing between the circuits, but with the grounds not connected. This leads to questions asking why the project doesn't work. You don't have to spend long reading the questions on this forum to see this is asked often. Here I attempt to explain the problem and why it matters to connect the grounds. Note that in all of the schematics that follow I have used a battery as a power sup… --- _[View the full topic](https://forum.arduino.cc/t/coding-help-vfd-to-lcd-or-oled/886919)._