An FPGA-embedded oscilloscope based on the IEEE Std.

Transcription

1 An FPGA-embedded oscilloscope based on the IEEE Std. Resumes a MSc. thesis submitted by Diogo Eloi Pinho (diogoeloi@hotmail.com) to the Polytechnic Institute of Porto School of Engineering (IPP/ISEP) - Portugal. Thesis supervised by Ricardo Costa. REC2015 XI JORNADAS SOBRE SISTEMAS RECONFIGURÁVEIS INSTITUTO SUPERIOR DE ENGENHARIA DO PORTO 5-6 DE FEVEREIRO DE 2015 R I C A R D O C O S T A R J I S E P. I P P. P T / H T T P : / / W W W. D E E. I S E P. I P P. P T / ~ R J C

2 Index Introduction Digital oscilloscopes Using FPGAs and the IEEE for designing embedded instruments Implemented oscilloscope Verification of the oscilloscope Conclusions 2/13

3 Introduction Instruments in Electrical Engineering laboratories Analogue Digital Stand-alone Embedded Modular Use JTAG / IJTAG interfaces. Adopted for performing specific validation, test and debug functions of other electronic circuits in the same chip or circuit board. But they can be implemented as a common (stand-alone or modular) digital instrument! 3/13

4 Digital oscilloscopes Mixed Signal Oscilloscopes (MSOs); Digital Sampling Oscilloscopes; Digital Phosphorus Oscilloscopes) (DPOs); Digital Storage Oscilloscopes (DSOs) 4/13

5 Using FPGAs and the IEEE for designing embedded instruments (e.g. digital oscilloscope) FPGA ADC / DAC Physical interfaces (RS232) E2PROM memory FPGA-based board to implement a digital oscilloscope (embedded instrument) Ethernet interface DRAM memory LCD display Buttons Digital I/0 pins JTAG interface LED indicators Buttons 5/13

6 Using FPGAs and the IEEE for designing embedded instruments (e.g. digital oscilloscope) Web APIs NCAP TIM Network Capable Application Processor IEEE1451.x commands TCs Transducer Interface Module TEDS Provides different IEEE commands (e.g. WriteTEDS; ReadTEDS, etc.) TEDS (Transducer Electronic Data Sheet) comprises data divided in Type Length Value (TLV fields) to indicate specific features and the current operation of a particular TC (Transducer Channel) 6/13

7 The implemented oscilloscope Digital oscilloscope Oscilloscope Time/Division Triggering Level: 0.00 Slope Up Down Command editor command to send replies command replies Send Coupling DC AC FPGA-based board (several blocks described in Verilog HDL) IEEE commands: (TCoperate, TCidle, ReadTEDS, WriteTEDS) Computer Interface (JAVA) 7/13

8 The implemented oscilloscope TEDS defines: oscilloscope as a sensor; units (volts); amplitudes (0.4 V to 2.9 V); resolution (0.15 mv defined according to the ADC); number of samples (2500); trigger level and slope; immediate mode to transmit samples to the computer interface; and scale definitions for representation in the computer interface IEEE commands TCoperate Turns ON the oscilloscope; TCidle Turns OFF; TEDS Read/Write to access the TEDS s fields. MSB TC ID (2 octets) command MSB Class (1 octet) Success / fail reply flag (2 octets) Function (1 octet) Length (2 octets) Length (2 octets) lsb data (variable num. octets) lsb data (variable num. octets) 8/13

9 Implemented oscilloscope IEEE commands MSB TC ID (2 octets) command Class (1 octet) Function (1 octet) Length (2 octets) lsb data (variable num. octets) MSB Success / fail reply flag (2 octets) Length (2 octets) lsb data (variable num. octets) 9/13

10 The implemented oscilloscope Changing a specific button means sending an IEEE command to change the TEDS s fields (WriteTEDS) samples presented Turns ON/OFF (TCoperate /TCidle) Commands are sent to the TIM using the hexadecimal format and the replies retrieved in the same format. 10/13

11 Verification of the oscilloscope Serial Monitor (Applied commands and replies monitorization ) 11/13

12 Conclusions Digital stand-alone or modular instruments can be replaced by embedded instruments (more flexibility and a reduction of costs in their design); Reconfigurable devices, in particular FPGA-based boards, can be the adopted infrastructures for implementing embedded instruments; Describing the instruments in HDL (e.g. VHDL or Verilog) promotes their share and the use of different FPGAs to implement the infrastructure; The IEEE Std. (commands and TEDSs) is an interesting solution to standardize the design and the access to embedded instruments; The implemented solution intended to proved the possibility of embedding an instrument in a reconfigurable device (FPGA) using the IEEE Std. In the future, other devices, such as FPAAs, should be evaluated to implement embedded instruments! 12/13

13 Thanks for your attention! Ricardo Jorge Guedes da Silva Nunes da Costa Webpage: Acknowledgments: 13/13

14 FPGA utilization 14/13