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Drew and Bob’s Draft #1. Basic design ideas: Use any off the shelf SBC Use generic ~off the shelf pmc interface to PCI Leave open possibility to upgrade CPU’s Leave open possibility to support a 64 bit PCI SBC w/o modification to 9u card. Mechanical: sbc sits inside of 9u card, - PowerPoint PPT Presentation
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Drew and Bob’s Draft #1
Mechanical: sbc sits inside of 9u card,If SBC is 1 slot, the whole beta system
is 1 slot
SBC
9u
PMC
fpgafifos
Basic design ideas:•Use any off the shelf SBC•Use generic ~off the shelf pmc interface to PCI•Leave open possibility to upgrade CPU’s•Leave open possibility to support a 64 bit PCI SBC w/o modification to 9u card
64 bit bus
Note: all block diagrams are simplified here to concentrate on the 9u to PCI path, MBUS buffers for pio, ecl drivers, etc are not shown in detail
Short 2-3” cable
Altera 10K100
FIFOWCK
WEN
RCK
REN
MBDA
128
64
MBAD
Drivers
FIFOWCK
WEN
RCK
REN
MBARB
32
32
P2 Lines 16
PMC
13Control/Arb
33To ECL
12 To Hlink?
12 To Hlink?
64
64
DriversDrew and Bob’s Draft #1
Block Diagram
9u card
Bidirectional 64 bit bus for PIO, etcOne direction for DMA
Drew and Bob’s Draft #1
Comments: We included new drivers on the PMC and drivers on the
9u card because we expected that the TTL from the fifo’s, FPGA, and PMC might not be able drive the cable. I’m not sure this is aproblem after giving it more thought… (more later)
The FPGA model here is that the PMC card’s FPGA serves as a bridge between the local bus of the PCI interface and the private bus used to connect the PMC w/ the FPGA on the 9u card.
The 9u FPGA replaces the PIO/DMA/ and TSI devices and maybe also provides a new hotlink output. It also supports a custom interface to the PMC card.
Orsay Draft
Mechanical: SBC sits under the 9u card.Its PMC connector plugs into the
bottom of the 9u board, the is no PMC card – this eats two slots minimum.
SBC
9u
fpgafifos
Basic design ideas:•A single fpga can do the job instead of programming two of them•do away / PMC + cable•do away w/ drivers by keeping signal paths short in this design•Choose one off the shelf and9u card layout is done to mate w/ this boardpmc conn
Pci controller on 9u cardNo cable – hard, fixed connector
to SBC
32 bit buslocalbus
“piggyback” of SBC onto 9u card
Altera 20K200
MBDA
12832
MBAD
Drivers
FIFOWCK
WEN
RCK
REN
MBARB
32
32
P2 Lines 16
AMCC PCIInterface
32 A/D +Control/Arb
PCI interface local bus
33To ECL
Orsay Draft Block Diagram
9u cardFIFO
WCK
WEN
RCK
REN
FIFOWCK
WEN
RCK
REN
FIFOWCK
WEN
RCK
REN
Local bus module
Orsay Draft
Comments: One card to build, all function is on 9u card. Only one
local/private bus to control.No differential drivers used – FIFO output is buffered through FPGA, and bus lengths are kept short <~ 20 cm, so TTL can drive w/ no problems at 33MHz (local bus speed = PCI bus speed)
The 9u FPGA replaces the PIO/DMA/ and TSI devices. It now serves as the local bus interface.
Bob/Drew
+ use ~any SBC at any time+ 64-bit connection from 9u card allows added upgrade path for SBCs+ mechanicals similar to standard VME extender board
-two FPGA’s to program-two bus protocals-two boards to build (IF the cern card needs new drivers added…)
Orsay
+ one card to build+1 fpga to program+1 local bus protocal+all TTL interface to SBC (no differential drivers)
-fixed choice of SBC-essentially no upgrade path w/o major redesign-personal opinion odd mechanicals
A Combination of both drafts Block Diagram
I think the strengths of both designs can be combined as follows:
1. Route the output of the FIFO’s through the FPGA for some added buffering instead of asking them to drive the bus on the 9u card and the cable - this should keep max distances to <~ 20cm for any TTL output
2. Now we could actually use the CERN card w/ no modification at all. There are two ways to implement this1. Put a mindless program in the PMC fpga to pass the PCI controller’s local bus
straight out of the card. Then the 9u fpga will include a module to drive the local bus (33MHz w/ a 32 bit data width) ala ORSAY’s idea.
2. Go w/ a 64 bit private bus as planned and to some work in the PMC FPGA as we initially proposed (this could be done much later, as a upgrade project, if we don’t want to do it initially!) and build a higher bandwidth private bus
Altera 10K100
FIFOWCK
WEN
RCK
REN
MBDA
128
64
MBAD
Drivers
FIFOWCK
WEN
RCK
REN
MBARB
32
32
P2 Lines 16
PMC
Control/Arb+ 64 bits data
33To ECL
12 To Hlink?
12 To Hlink?
64
64
A Combination of both drafts Block Diagram
9u card77
Combined Design
+ still only have to design one card (PMC and SBC are truly off the shelf)+ trivial option for PMC FPGA coding (just pass local bus)+ all future upgrade advantages are still available i.e. maximum future flexibility w/o a significantly larger design/firmware effort + Firmware upgrades on 9U card can support HARDWARE upgrades on PMC/SBC cards