Simple PCIe FMC carrier SPEC issueshttps://ohwr.org/project/spec/issues2019-02-12T09:18:42Zhttps://ohwr.org/project/spec/issues/103Use smaller DDR3 memory to considerably reduce price2019-02-12T09:18:42ZErik van der BijUse smaller DDR3 memory to considerably reduce priceCurrently a 256 MByte RAM is used (MT41J128M16HA-15E). The price of this
component is a considerable part of the total price. Check with the
applications if a smaller type can be used. E.g. a 16 MByte version may
be almost $45 cheaper.Grzegorz KasprowiczGrzegorz Kasprowiczhttps://ohwr.org/project/spec/issues/102Add LHC equipment name "CFEIA" on PCB2019-02-12T09:18:41ZErik van der BijAdd LHC equipment name "CFEIA" on PCBThis will help in stock management. Not sure if can also add to the
front-panel.Grzegorz KasprowiczGrzegorz Kasprowiczhttps://ohwr.org/project/spec/issues/100NUMONYX M25P128-VMF6G difficult to find2019-02-12T09:18:40ZErik van der BijNUMONYX M25P128-VMF6G difficult to findSee https://www.ohwr.org/work_packages/119
Update schematics and design fileshttps://ohwr.org/project/spec/issues/91Oscillator selection2019-02-12T09:18:33ZTomasz WlostowskiOscillator selectionIssues related to IVT3025/CFPT9301 oscillators, mounted by default on
SPEC boards:
\- cannot be used for White Rabbit DMTD clock because of too low tuning
range. We need 100 ppm.
\- can cause soldering issues (IVT3025 consists of two ceramic plates
soldered together already)
\- CFPT9301 oscillator is very expensive. Could be replaced with a much
cheaper VM53S3 oscillator (20, 25 or 40 MHz) with a 3 V LDO regulator
(for example LP5951MF-3.0).
\- both oscillators don't have to be of exactly 25 MHz. The 25 MHz
version seems to be difficult to get, but it could be replaced with more
popular 20 or 40 MHz. CDCM61004 PLL configuration resistors would need
to be changed to produce 125 MHz REFCLK from the new input frequency.https://ohwr.org/project/spec/issues/88Factory programming of GN4124 EEPROM2019-02-12T09:18:31ZTomasz WlostowskiFactory programming of GN4124 EEPROMFigure out an efficient way of factory programming the GN4124
configuration EEPROM.
Possible solution: use a jumper instead of R150, so it can be shorted to
enable/disable the EEPROM without a need for soldering.https://ohwr.org/project/spec/issues/87Firmware loader: host-side selection between GN4124 and Flash memory2019-02-12T09:18:31ZTomasz WlostowskiFirmware loader: host-side selection between GN4124 and Flash memoryIn the current version of SPEC board, choosing between the FPGA
bitstream from internal EEPROM or the Gennum requires replacing some
resistors on the PCB. Find a way of doing that without soldering.
Possible solution: use a multiplexer driven by GN4124 GPIO pin to select
the boot method.https://ohwr.org/project/spec/issues/86Operation without a PC2019-02-12T09:18:30ZTomasz WlostowskiOperation without a PCAdd an external 12 V power socket and PCB stand-off mounting holes, so
the card can be used without a PC.https://ohwr.org/project/spec/issues/85Use smaller layer indicator2019-02-12T09:18:30ZProjectsUse smaller layer indicatorUse smaller layer indicator.
See FMC delay 1ns as an example.https://ohwr.org/project/spec/issues/83Replace fuses by resetable type2019-02-12T09:18:28ZProjectsReplace fuses by resetable typeFuses on power supplies should be replaced by resettable fuses.https://ohwr.org/project/spec/issues/82FMC standoffs and front panel connection to GND2019-02-12T09:18:28ZProjectsFMC standoffs and front panel connection to GNDDefine a coherent method to connect FMC standoffs and front panel to GND
on mezzanines and carriers.https://ohwr.org/project/spec/issues/81Use 3P3V for powering the FMC.2019-02-12T09:18:26ZTomasz WlostowskiUse 3P3V for powering the FMC.Max allowed current from the 3.3V rail in a FMC card is 3 A. Our PSU is
6 A. Consider powering the FMC from the built-in power supply, this
would facilitate the stand-alone operation.https://ohwr.org/project/spec/issues/80Add a connector for external clock and timecode input2019-02-12T09:18:26ZTomasz WlostowskiAdd a connector for external clock and timecode inputAdd a SATA connector for providing an external 125 MHz and PPS/UTC
timecode reference to avoid using WhiteRabbit port in every card in the
same PC if all cards need synchronozation.https://ohwr.org/project/spec/issues/79DAC replacement2019-02-12T09:18:25ZTomasz WlostowskiDAC replacementReplace the LTC2641 DAC with a cheaper chip, such as AD5662 to reduce
the total cost of components.https://ohwr.org/project/spec/issues/78eSATA -> SATA connectors2019-02-12T09:18:24ZTomasz WlostowskieSATA -> SATA connectorsUse SATA connectors instead of eSATA. Add 2nd SATA port connected to the
unused GTP channel.https://ohwr.org/project/spec/issues/77Air flow under FMC card can be improved by cut-out2019-02-12T09:18:23ZErik van der BijAir flow under FMC card can be improved by cut-outThere is little airflow under the FMC mezzanine as most of the bottom
side is blocked by the SFP cage.
As there are no components on the carrier, a large cutout can be made
under the FMC to improve the airflow.
See for an example
http://www.alpha-data.com/products.php?product=adpe-xrc-5tTomasz WlostowskiTomasz Wlostowskihttps://ohwr.org/project/spec/issues/71V1.1 - TPS51200 regulator is out of stock2019-02-12T09:18:20ZTomasz WlostowskiV1.1 - TPS51200 regulator is out of stockTPS51200 is unavailable at most distributors. I suggest replacing IC5
and IC17 with TPS51100 (MSOP package), it provides identical
functionality.https://ohwr.org/project/spec/issues/66Prodution test program: add field for manufacturer's ID2019-02-12T09:18:13ZErik van der BijProdution test program: add field for manufacturer's IDThe production test program will read a barcode of CERN's production.
This contains a serial number.
Manufacturers likely will have their own production ID too. It would be
nice to also request that number and store it in the logfiles for
further use.
Also consider what happens for productions that are not for CERN (i.e.
CERN does not provide the barcodes).Samuel Iglesias GonsálvezSamuel Iglesias Gonsálvezhttps://ohwr.org/project/spec/issues/65Jumper pins JP6 seems difficult to get. Change order reference.2019-02-12T09:18:13ZErik van der BijJumper pins JP6 seems difficult to get. Change order reference.The simple two contacts for a jumper (JP6) with reference KONTEK COMATEL
386.0358.1.02.440 seem difficult to order.
Consider changing in the schematic and BOM by Farnell/ 1022247 (HARWIN -
M20-9990246).https://ohwr.org/project/spec/issues/63Define PCIe vendor/manufacturer ID and device ID2019-02-12T09:18:11ZProjectsDefine PCIe vendor/manufacturer ID and device IDCERN vendor IDs for : PCI = 0x10DC
The SPEC should be registered here :
https://ess.web.cern.ch/ESS/boardIDistribution/PHP/https://ohwr.org/project/spec/issues/62V2 - Swap Tx and Rx on one of the SATA connector2019-02-12T09:18:11ZProjectsV2 - Swap Tx and Rx on one of the SATA connectorTo be able to use standard SATA cable to chain SPEC board, Tx and Rx
must be swapped on one of the SATA connector.