hi,You will need an A2D (analogue data acquisition device) with a GPIB interface
is that possible to power from DAQ to the sensor?You need to supply power to the hall sensor (normally 5VDC) and amplify the output to be within the input range sensitivity of the DAQ. The signal level also depends on size of the magnetic signals
http://www.hbm.com/fileadmin/mediapool/hbmdoc/technical/b0554.pdfDoes the DAQ output clean power say 5 VDC with Iload = 20 mA ?