M Series data acquisition (DAQ) external devices for the USB bus offer up to 32 analog input channels and data acquisition rates of up to 1.25 MS/s. NI (National Instruments) USB-6251 and USB-6259 DAQ combine M Series capabilities with USB plug-and-play connectivity and high-speed signal streaming technology. The USB-6251 and USB-6259 DAQ devices feature the parallel and simultaneous streaming technology on the USB bus. The devices also include M Series features similar to their PCI/PXI counterparts, such as up to 32 16-bit, 1.25 MS/s analog input channels; four 16-bit 2.8 MS/s analog output channels; 32 clocked and correlated digital I/O channels; and two timing counters.