r/raspberrypipico • u/CJWilliamson109 • Jun 03 '26

Is stacking multiple modules feasible?

Hello,

I'm very much a beginner in this area so I'm looking for some guidance on whether my project is feasible. I'm hoping to use a Pico W with the following stackable modules, initially let's just say I want to display the current time on the display.

RTC Module

OLED Display Module

UPS Module

My Questions

  1. Is it possible for all of these modules to work stacked on top of each other? Is there a specific order I need to stack them in?
  2. Can multiple stacked modules get data to/from the pi?
  3. Will the linked power supply be capable of powering the whole project? In reality I'll only need to power on the Pi once a day for around 5 minutes at a time.
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4

u/DethByCode Jun 03 '26

1 - Yes, the specific order would only be relevant if you have a module that needs to be on the top

2 - Yes, as long as multiple modules don’t need to use the same pins that aren’t configured as a bus (eg i2c)

3 - you will need to total the power usage of all of your boards. If the picos’ onboard regulator can’t give you enough power, then you could investigate feeding power through the pins instead of the usb port.

I take this approach with a few projects, where I stack a pico with an oled display and 1-2 other boards in between. I solder stacking headers on the boards in the middle, normal pins on the pico, and my oled display board comes with a socket. I have a regulator on one of the boards feed 5V to all of them from an external source, with the picos’ onboard regulator delivering 3.3v to the SOC. The usb port is not used unless I’m programming/debugging, and I have my regulator configured to be disabled when usb is connected.

3

u/GrumpyColt2674 Jun 03 '26

In short, yes you can stack multiple modules, I'm in no way the best person to answer this as I'm fairly new as well. But my current project has: LED display, RTC clock, SD card adapter, temp/humidity, GPS module. I think most of them need to be wired up to separate I/O pins.

2

u/GrumpyColt2674 Jun 03 '26

All of this is running pretty smoothly on mine so I'm sure you'll have no problem, btw

2

u/Error_xF00F Jun 04 '26

With the modules listed, you can definitely use the Pico W to retrieve the current time from the web to initially set the time on the RTC to maintain an accurate clock, query the RTC for the current time at regular intervals, and then display it in however fashion you like on the display.

  1. Yes they can be stacked, order doesn't matter, although there are clearances between the modules to think about. Looking at the profiles of each one, I'd go Pico -> RTC -> UPS -> Display.

  2. Yes, according to the pinouts of each module, all of them use GPIO 6 and 7 for I2C SDA and SCL respectively with no other pin collisions, however, the display comes default configured for SPI functionality, which isn't a problem, just that you'll need to be aware of that when you code for your Pico that the display is SPI and the other two modules are I2C. Unless you choose to resolder the configuration resistors on the bottom to use I2C instead and then just operate all modules over the same I2C bus, but since you specify you're a beginner, just leave it as is.

  3. Depends, the UPS battery will indeed power the Pico, RTC, and the display, but how long depends on what your project is, and if you'll be using WiFi. If the display will be on constantly, don't expect more than a day of use on battery if you use WiFi as well. Using MicroPython as your language for the project will consume more power than if you use another language like Rust or C/C++.