The OpenBCI documentation shows: https://docs.openbci.com/GettingStarted/Biosensing-Setups/ECGSetup/ how to make a 3-Lead ECG with Cyton or Ganglion Boards. It first shows step by step for a 3-Lead ECG how to get one channel of live ECG data. Then it shows step by step in the 5-Lead ECG guide how to get 4 channels of live ECG data. …