The only output I get is black/empty unless I shine a very bright light at the sensor.

Even adjusting the focus doesn't change it. It always stays black/empty.

Hello,
I am experimenting with the ADNS3080 and an Arduino Micro.
I could see, that the overflow Bit is not set, even if I provoke an overflow, i.e. slow reading rate to read the motion data and "fast" movement with my test-plane, leading to x- or y increments of 127, -128 respectively. I am using the motion burst mode. I tested it with two different ADNS3080. I occurs to me, that the OVF Bit in the motion register is never set.
Could you observe similar behavior?

Thank you in advance and best regards
Michael

P.S. Thank you for your neat library!

// SPI pins:
#define PIN_RESET 45
#define PIN_CS 47

Dear sir:
pin_cs is which pin for adns3080? It just has GND, 5V, 3V,NCS, MISO, MOSI, SCLK, RST, NPD, LED