Fabric System Architecture Design: two distinct board designs; replicate and connect –modularity allows us to build any configuration of size 2 n Board 1: Quad Raw Board Board 2: I/O & Memory Board

The Saman Flip How do we use the same board designs for every position in the fabric? –Quad board symmetric in both dimensions –IO Board symmetric about x-axis compensate for board flip in firmware

Quad Board 4 RAW chips per board pin MICTOR connectors total (4 per side) Power distributed over separate cables from other signals Connectors are stacked to save space

Quad Board Layout Anant, I created the graphic in the previous slide to overlay exactly on this one. Their placement on the slide is also the same. I recommend fading from the previous slide to this one, so the audience can make the conceptual leap from the block diagram to the real layout. 11”

I/O & Memory Board 4 FPGAs 2 64-bit PCI slots 2 Expansion Ports (same as on Raw Handheld board) 4 SDRAM banks symmetric design (thanks Saman!) 11”

Here’s the IO Board schematic in case you want to use it…

Clock Distribution from external input Synchronized clocks for all Raw chips in fabric Delay-Locked Loop uses feedback to tune delay line for clock synchronization Dip switches keep clock dist. general  no custom firmware

Power Distribution 48V distributed to all boards, then down- converted DC-DC converters on each board –1.8V Raw core –1.5V Raw I/O –3V other logic –1.5V is also further down converted to 0.75V supply for HSTL termination System-wide power supply can be up to 3kW

Power Distribution distributed separately from signals external power supply feeds top and bottom rows of I/O Boards power supply

Clock Distribution signal generated and distributed from a center board over MICTOR connectors uses PLLs to deskew the clock at each connection every quad board sends and receives a copy of the clock to its neighbors and we can select which of the input clocks to use using dip switches clock generator

Reset Distribution signal generated by one of the I/O boards and distributed over MICTOR connectors reset originates here