Ocean Optics' S2000 Spectrometer platform supports stacking slave spectrometers on top of the master spectrometer. In the normal operating mode, data is acquired sequentially from the stack of spectrometers. The master's data is acquired first, then data from the first slave, then data from the second slave, etc. When all channels have been acquired, the master channel once again acquires data. At an electronic level, all optical benches are acquiring and reading out spectral data during each acquisition period. It is the responsibility of the A/D card to select which spectrometer channel to "listen" to when the spectrometers read out their data. With the introduction of the ADC1000 product line (ADC1000 and ADC1000-USB) and subsequently the ADC2000-PCI, Ocean Optics added a feature called Pixel Rotation. The purpose of this mode is to read out spectral data from all spectrometers in the stack with each acquisition cycle. Pixel Rotation does this by switching which spectrometer it is digitizing data from with each pixel acquired