Beginner question on pins

[DrDiettrich]

@ariamisblk

a schematic that has 5 pins VCC, GND, DIN, CLK, CS, but the version of Matrix I have only has 4, VSS, GND, SDA, SCL.

These apply to different interfaces. DIN, CLK and CS apply to the SPI interface, while SDA and SCL are used by I2C. Search for the document that applies to your module.