I've been getting sensor output like

C: -1.00
L: -1.00
R: 120.38
C: -1.00
L: -1.00
R: 122.97

(C is the centre sensor, L is the left sensor, and R is the right sensor).

I wonder if it's bad sensors or what.

Also, had to vendor the SparkFun SCMD library due to an I2C init issue - the upstream tries to start in slave mode.