All hardware design files are free - licensed under CERN Open Hardware Licence ( CERN OHL ).
Hardware is built around Xilinx® Spartan®-6 LX9 FPGA which contains digital logic. All hardware settings are controlled via program GUI and transferred to FPGA registers via Cypress’s EZ-USB® FX2LP™ chip. Below you can find more information about individual hardware components.
Two analog channels are available as oscilloscope inputs. Both oscilloscope channels are protected for overvoltage up to +/- 50 V. Input coupling selection is available ( DC, AC, GND ) and is controlled via program GUI. Input signals are buffered via analog front end for impedance, level ( gain ) and offset adjustments. Analog signals are sampled at 100 Mhz through an 10-bit dual analog-to-digital converter ( ADC ). Digital samples are then processed by FPGA which contains trigger logic. When trigger condition is met, samples are first buffered in FPGA internal RAM ( BRAM ) and then transferred to PC via FX2LP USB chip.
There are two generator outputs with short circuit and overvoltage protection ( +/- 50 V ). Generator channels have 50 Ohm internal impedance which allows connection to various equipment. User can select frequency, output level and offset via program GUI. Generator settings are transferred to FPGA registers via FX2LP USB chip. Digital samples are generated in FPGA at 50 Mhz and sent to digital-to-analog converter ( DAC ). Simple signals are derived from counters. Sine wave output is generated with the help of CORDIC algorithm, so that outputs of arbitrary frequency can be obtained. User can also select a file containing custom waveform samples which is uploaded to FPGA internal memory.
16-bit digital interface is sampled at 100 Mhz and is logically divided into two 8-bit channel groups. Each channel group can be independently selected as input ( Logic analyzer ) or output ( Pattern generator ). Digital interface voltage can be adjusted - ranging from 1,25 V to 3,3 V, but inputs are designed to accept also 5 V. Selected interface voltage is also available on dedicated output pins and can be used for voltage supply. Custom digital samples for pattern generator can be uploaded via GUI and internal clock divider is available to control the output frequency. It is also possible to override individual outputs with a logic 'LOW' or 'HIGH' at any time.
Logic Analyzer / Pattern Generator