Field Programmable Gate Array (FPGA)

1. Canary Islands, SPAIN“Hardware Developments for Fast Control Systems”OPTICON planning meeting UKATC, Edinburgh

2. Field Programmable Gate Array (FPGA) • Started on mid-80s • Configurable logic blocks • 65 nm, 550 MHz • Interface to many standards • Hundreds of I/O • Recently grown to big sizes

3. FPGA main features • Parallelism • Speed • Low cost • Flexibility • Tiny size, low power consumption, low weight

4. FPGA vs µPs, DSPs, GPUs • FPGAs helped conventional processors doing interfacing, glue logic,... • FPGAs have grown to a level capable of accepting a microprocessor inside... • Traditional approach is to manufacture big quantities of a general purpose microelectronics hardware, and write a (specific) program to solve the specific task • Using FPGAs, we can get rid of any program and produce the hardware adequate for each task.

5. FPGA: Transversal key technology • Adaptive optics • Detector controllers • Phasing control for segmented mirrors • High time resolution astronomy • Lossless data compression • On-line data reduction • …

6. IAC Example • In-house technology development project • Examine FPGA technology and evaluate its potential for AO • Develop know-how to be used in future AO projects for astronomy and other fields • L.F. Rodríguez Ramos et al. “FPGA adaptive optics system test bench”. Proc. SPIE 5903, 120-128, 2005 • J.G. Marichal-Hernández, L.F. Rodríguez-Ramos et al. “Atmospheric wavefront phase recovery using specialized hardware: GPUs and FPGAs”. Applied Optics 2005 Dec 10;44(35):7587-94 • L.F. Rodríguez Ramos et al. “Testing FPGAs for real-time control of adaptive optics in giant telescopes”. Proc. SPIE 6272, 2006

7. Project team • People • Luis F. Rodriguez Ramos PI & PM • Teodora Viera Control Algorithm • José V. Gigante Camera I/F, displays and centroid computation • Fernando Gago Frame grabbing • Guillermo Herrera DACs I/F • Angel Alonso Optics • Nicolas Descharmes Optics • Budget • 4000 man-hours (~2 man-yr) • 25 K€ ($30 K)

8. TS L1 MO ATM LS D2 D1 L3 BS2 50/50 LA L4 BS1 50/50 SHC D3 NDF L2 MMDM SC Experimental setup

9. Electronic system setup

10. Electronic system setup

11. FPGA occupancy example • Image recomposing 1% • Centroid calculation 35% • Matrix computation 3% • Linearization 6% • PI control 2% • Display 14% • Housekeeping 9% • TOTAL 70%

12. Results I Frame clock centroids correction frames, centroids and actuation Last two rows and actuation

13. 39 actuators Servo ON Results II Switching voltage pattern added to the first ring of actuators (7) 64 errors in X Servo OFF

14. Joint development proposed • Astronomy related building blocks • Practical System prototype

15. Building blocks development • Never start from scratch: Lots of commercially available IP Cores plus... • Astronomy related building blocks, to be developed in a joint effort and made available to the community. • Previous work needed in • Block identifying, • Common development methodology, • Agreeing interfaces • Synthesis software evaluation • …

16. Building block examples • FFT (2D and multi-D) • Centroid computation • Image correlation • Gaussian fitting • Sparse Matrix • Floating point arithmetic • Camera interface • Inter-boards and intra-board communication • Detector pre-processing (Flat, slope, cosmetics…) • Lossless data compression • Intersystem Synchronization • ...

17. ELT AO Prototype • Massively parallel FPGA-only system capable of implementing all the aspects of the adaptive optics of a giant telescope, including multi-guide star atmospheric tomography • ELT simulation optical bench • Hardware Processing engine (subcontract) • AO Algorithm reformulation • AO Prototype simulation • AO Prototype laboratory tests • Telescope tests at OGS(1m) + WHT(4,2) + GTC(10m)

18. Work breakdown and schedule

19. Cost idea • Coordination: 20.000 €/y • Man-power: 200.000 €/y • Subcontracts: 50.000 € • TOTAL approx: 1.2 M€

20. Thank you