Create your ultimate i2c & spi general-purpose i/os tier list and rank everything from S tier to D tier. This i2c & spi general-purpose i/os ranking tool lets you compare, vote, and share your tier list with the community. Looking for the best i2c & spi general-purpose i/os? Use this tier list to settle the debate and see how your i2c & spi general-purpose i/os rankings stack up against other users on TierBuddy.