waveshare GPIO Expander Module Board for Raspberry Pi Pico, with 1x Raspberry Pi Standard 40PIN Header and 1x Pico 2x20PIN Header,Allows Connecting Raspberry Pi Hats and Pico Expansion Boards

I ordered the Waveshare Raspberry Pi Pico Dual I/O expander and a different brand Arduino Nano expander at the same time. The quality and build of the Waveshare expander is light years ahead of the other brand. The edges of the board are finished, the silk screening is very readable and the soldering looks good. I have not tested how it works but if you are reading this assume it works because if it doesn't I would have edited my review. I do recommend.

It's a nice board, but realize the Pico pins match the labeled pins under "PI HAT", but the "PI HAT" GPIO pins do NOT match all the Raspberry Pi GPIO pinouts. Note for example in the product picture the pin labeled GP14 should actually be GP4 if it was to match the Raspberry Pi's GPIO pinout.Comparing with the Canakit Raspberry Pi GPIO Header Quick Reference card:Waveshare | Actual Raspberry Pi (what the Waveshare pin SHOULD be)----pin #--- |-------pin #-------GP14........................GP4GP4..........................GP14GP5..........................GP15GP11........................GP10GP10........................GP11GP12........................GP9GP10........................GP11GP15........................GP5GP9..........................GP12That's a total of 9 pins that are misplaced on the board. I say 'misplaced' instead of mislabeled only because one could just use the pinouts as they are on the board. For example, pin 14 labeled on the Pico does match up with the pin labeled as GP14 under "PI HAT". All the misplaced pins have electrical continuity with the same pin numbers on the Pico. Major problems will arise, though, when trying to connect a ribbon cable, for example, from the "PI HAT" pins to another Pi-compatible device whose pins are properly placed and labeled. In other words, pin 4 on the board will NOT match up correctly with pin 4 on the Pi-compatible device.I sent an email to Waveshare about this, but they never responded.Again, nice board, but there's no excuse for wrong pin placement. Makes me think Quality Control is lacking. Someone at Waveshare should have spotted these obvious mistakes.