SPEC7 Features
SPEC7 Features
- 2-lane PCIe Gen2
- Same 1 GByte/s total speed as 4-lane PCIe Gen1 on SPEC. Bridge integrated in FPGA.
- Xilinx Zynq FPGA with ARM processor integrated
-
XC7Z030-1FBG676C (~206 Euro) (-1= slowest, commercial temp
range, fast enough for most applications?)
- 4 GTX receivers (2 used for PCIe, 1 for SFP, 1 for FMC - as on SPEC - and none for SATA).
- Possibility to mount Z035: XC7Z035-1FBG676C (~800 Euro)
- 8 GTX receivers (2 used for PCIe, 1 for SFP, 3 for FMC, and 2 either for a) SATA, b) 4-lane PCIe, or c) FMC)
-
XC7Z030-1FBG676C (~206 Euro) (-1= slowest, commercial temp
range, fast enough for most applications?)
- FMC slot with high pin count (HPC) connector
- Vadj fixed to 2.5V
- Fully populated LA bank
- All 34 differential pairs connected, 1 GTP transceiver with clock, 2 clock pairs, JTAG, I2C (as on SPEC)
- Partial connectivity of HPC part
- xx signals on HA bank
- DP1_M2C/C2M and DP2_M2C/2CM connected to two GTX transceivers only when Xilinx Z035 mounted
- Check if possible to make compatible to VFC-HD
- Clocking resources
- 1x 10-280 MHz I2C Programmable XO Oscillator, starts up at 100 MHz (Silicon Labs Si570, freely usable)
- 1x 125 MHz TCXO controlled by a DAC with SPI interface
- 1x 124.992 MHz VCXO controlled by a DAC with SPI interface
- 1x low-jitter frequency synthesizer (TI CDCM61004, fixed configuration, Fout=125 MHz, used by White Rabbit PTP core)
- On board memory
- 1x SO-DIMM socket standard mounted with xx Gbit (xx MByte) DDR3
- MicroSD slot for flash memory
- 1x SPI xx Mbit flash PROM for multiboot FPGA powerup configuration, storage of the FPGA firmware or of critical data
- Miscellaneous
- On-board thermometer IC (DS18B20U+)
- Unique 64-bit identifier (DS18B20U+)
- Front panel containing
- 1x Small Formfactor Pluggable (SFP) cage for fibre-optic transceiver (WhiteRabbit support). 1.25 and 2.5 Gbps. 10 Gbps?
- Programmable Red and Green LEDs
- FMC front panel
- Internal connectors
- 1x JTAG header for Xilinx programming during debugging
- 2x SATA connector
- Default connected to buffered LVDS general purpose I/O
- With Z035 version may be connected to GTX (in which case no additional 2 GTX on FMC connector)
- 1x mini USB AB (USB-UART bridge)
- Footprint for High-speed connector for PPS in/out, 10MHz in, tx-abscal, rx-abscal, refclock. 6 signals to be transferred in a differential way Samtec Bulls-Eye connector (just a land pattern for 22 signals on the PCB).
- FPGA configuration. The FPGA can optionally be programmed from:
- JTAG header
- SPI 32Mbit flash PROM
- Stand-alone features
- External 12V power supply connector
- Mini USB connector
- 4 LEDs
- 2 buttons
- Power consumption: 5-12 Watt, depending on application
- Optimised for cost
- 8-layer PCB
- Optional cooling fan for the mezzanine.
Functional differences with SPEC
Gained functionality
- Larger, modern Zynq Z030 Xilinx with integrated ARM processor
- Additional signals on FMC connector (partial HPC bank population, including possibility of two or four extra GTX lines with Z035 upgrade)
- Possibility of double PCIe bandwidth (2 GByte/s with Z035 upgrade)
- DDR3 on SO-DIMM socket (reduces obsolescence, allows larger memory)
- MicroSD slot for flash memory
- Improved oscillators for lower jitter White Rabbit
- Prepared for absolute calibration of White Rabbit
- Prepared for installation of a cooling fan
Lost functionality
- SATA connectors are not connected to GTX lines on default Z030
Xilinx but to buffered LVDS.
- With Z035 SATA possibility to order connection to GTX (default buffered LVDS).
Cost of Alternatives
Existing SPEC: 180 Euro component cost (without PCB and front-panel) when bought in large quantities (several hundreds in one time).
- Replacing Gennum: (57 Euro) and Spartan (40 Euro)
Alternative Xilinx Zynq series with ARM processor integrated:
- Default: XC7Z030-1FBG676C (~206 Euro) (-1= slower, commercial temp
range, will be fast enough for most applications?)
- XC7Z030-2FBG676E (~285 Euro) (+79 Euro) (-2=faster, Extended temp range only, not available in commercial temp range)
- Z035: 8 GTX receivers (4 used for PCIe, 1 for SFP, 1 for FMC - as on
SPEC - and 2 for SATA). Makes it too expensive?
- XC7Z035-2FBG676E (~1100 Euro) (-2=faster, Extended temp range only, not available in commercial temp range)
- XC7Z035-1FBG676C (~800 Euro)
(Xilinx list prices compared for additional cost)
Total: with all options, 115 Euro extra cost (Xilinx, HPC), total cost price 295 Euro. (cf. 180 SPEC without PCB and front-panel)
Erik van der Bij, Peter Jansweijer - 15 February 2018