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 - same as on SPEC)
- Possibility to mount Z035: XC7Z035-1FBG676C or XC7Z045-1FBG676C
- 8 GTX receivers (2 used for PCIe, 1 for SFP, 3 for FMC, and 2 either for a) 4-lane PCIe or b) FMC)
- FBG767 pacakge has GTX tranceivers up to 6.6 Gb/s, FFG676 package enabled exploration of 10 Gb/s (see table 3 of zynq-7000-product-selection-guide)
- FBG676 package and FFG676 are footprint compatible (see note 1 on page 3 of zynq-7000-product-selection-guide)
-
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)
- Limited, 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
- 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 (used by White Rabbit PTP core) (Crystek CVPD-922 model)
- 1x 124.992 MHz VCXO controlled by a DAC with SPI interface (used by White Rabbit PTP core) (Crystek CVPD-922 model)
- On board memory
- 1x 8 Gbit (1 GByte) DDR3 IC
- 1x SPI xx Mbit flash PROM for multiboot FPGA powerup configuration, storage of the FPGA firmware
- 64K (8K x 8-bit) I2C Serial EEPROM (24AA64T-I/MC) for storing serial number, calibration parameters and other critical data
- Slot for flash memory for storing programs (MicroSD, UFS or MMC?)
- 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, 2.5 and 10 Gbps
- Programmable Red and Green LEDs
- FMC front panel
- Internal connectors
- 1x JTAG header for Xilinx programming during debugging
- 2x 14-pin header connector connected to GPIO, with ESD protection
- 1x mini USB
- Can serve two UARTs over the same single mini-USB connector with CP2105 - Dual UART bridge IC
- Samtec Bulls-Eye connector (22 signals on the
PCB, 6 cm2 land pattern,
user mountable connector)
- For PPS in/out, 10MHz in, tx-abscal, rx-abscal, refclock. 6 signals to be transferred in a differential way
- FPGA configuration. The FPGA can optionally be programmed from:
- JTAG header
- SPI xx Mbit 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)
- Upgrade to Z035 and Z045 possible
- Two or four extra GTX lines on FMC connector
- Possibility of doubling PCIe bandwidth (2 GByte/s), but then only two extra GTX lines on FMC connector
- Slot for flash memory (MicroSD, UFS or MMC?) for storing programs
- Added 64K (8K x 8-bit) I2C Serial EEPROM (24AA64T-I/MC) for storing serial number, calibration parameters and other critical data separate from FPGA configuration
- SFP+ at maximum 10 Gbps, instead of SFP at max 2.5 Gbps
- 1 GB DDR3 instead of 256 MB
- Dual UART on same mini-USB connector (e.g. for WR GUI and ARM processor)
- Improved oscillators for lower jitter White Rabbit
- Prepared for absolute calibration of White Rabbit
- Prepared for installation of a cooling fan
Changed functionality
- SATA connectors replaced by 14-pin headers. LVDS, GPIO connected, not to GTX anymore
- PCB board size likely will be larger
- Component price likely almost doubled
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, 145 Euro extra cost (Xilinx, HPC,
oscillators), total cost price 325 Euro. (cf. 180 SPEC). Prices without
PCB and front-panel.
PCB will also be more expensive (likely larger, more layers). Memory
cost also higher as 1GB instead of 256 MB.
Verify if possible to make low-cost version (cheaper oscillators, LPC
with less layers)
Erik van der Bij, Peter Jansweijer - 7 March 2018