SPEC7 Specification gathering
This wiki page describes different discussion points for the specification of the SPEC7.
Under discussion
FMC HPC or LPC
- use case for HPC?
- Makes that large FPGA should be used
FMC connector
- Vadj
- programmable IC, or just a few values and selection with jumpers?
FPGA family
- Kintex 7
- FBG676 package allows 70T, 160T, 325T and 410T sizes on the same
footprint.
- Default 160T.
- 8 GTX Transceivers max (4 used for PCIe, 2 for SFP, 2 left for FMC).
- Check if a 70T in FBG484 package can be used on footprint of FBG676
- FBG676 package allows 70T, 160T, 325T and 410T sizes on the same
footprint.
- Artix-7
- only if LPC
- low price
SFP
- Double SFP for allowing redundant links?
- not possible to fit on PCIe front-panel
- Image of double FMC cage with LEDs
- Image of double decker FMC cage with LEDs":https://media.rs-online.com/t_large/R7871705-01.jpg
- Could maybe fit if would make 2-slot card when optional heatsink/fan solution that extends it into the neighboring slot. Double decker would not work here though.
- Compact SFP (CSFP)?
- Has two bidi standard SFPs in one SFP module
- CSFPs have a little different pinout comparing to the standard SFPs. Same mechanics as standard SFP (Wikipedia).
- Difference between SFP, bidi SFP and CSFP
- CSFP Delta CSFP-33-A4K1DBT (pinout on page 4)
- Check if use of CSFP would limit the use of standard SFP modules
RAM
- SO-DIMM socket for RAM
- Or directly assembled RAM IC?
FLASH storage
- MicroSD slot?
USB
- mini USB connector (as on SPEC)
- micro USB-OTG (so it can act as host and as slave). But then we should rename the card to SPUEC or SUPEC (U for USB). Perhaps this is a crazy idea, but it is nice to think that users can plug'n'play the SPUEC/SUPEC on their laptop :) (FV)
PCB
- 10 layer PCB so that layout can be optimised for low-jitter oscillator
Accepted
SATA
- Keep same SATA connectors as on SPEC.
- Is a connector specifically for internal use (i.e., not panel-mounted).
- Planned to be used on SPEC for daisy-chaining triggers between SPECs with FMC-ADCs with modified gateware.
Rejected
15 January 2018