Camera+Link

For details on the Camera Link specification and the underlying protocol, see: and .

Camera Link is based on the National Semiconductor "Channel Link". To be a 100% compatible Camera Link device, both the camera transmitter and the interface card receiver must be National Semiconductor devices, specifically, DS90CR2xxx and DS90LV04x chipsets.

Camera Link has 3 basic modes, "base", "medium", and "full". Base uses only one of the Camera Link connectors (most interface cards come equipped with two connectors to be able to run in anyone of these modes), while medium and full use two Camera Link connectors. Since the Andor Xion camera has the potential to only run in base mode, pretty much any card that we get will work.

Latency: None of the "simple to obtain" brochures and literature have information on latency, they all talk about modes and throughputs, and whether the interface can provide power through the link. That said, the information on the National Semiconductor Channel Link chip lists something that might be useful: "2.5 / 0 ns Set & Hold Times on TxINPUTs". I interpret this to mean that it takes 2.5 ns to set a word and 0 ns to hold that value. Since the computer DRAM clocking is on the order of 10-40 ns, I suspect most of the latency is going to be in the computer DMA, transfer which is probably why the interface card manufacturers don't list it.

PCI vs PCIe: Camera Link interface cards come in many different formats, but in only two basic bus interfaces, PCI and PCIe. Base and medium modes can work with a PCI bus, but full mode requires a PCIe. A few of the cards have PCI versions that fit in 3U compact PCI chassis (like the metrology fiber interface in the OPLE rack), 6U compact PCI, and PC104. The AO computer at the telescope has both PCI and PCIe interfaces, so any traditional bus interface PCI/PCIe will work for us. The following table lists typical data rates for the various interfaces.
 * || Peak || Continuous || Max Pixel Rate ||
 * PCI 32-bit || 130 MB/sec || 100 MB/sec || 85 MHz ||
 * PCI 64-bit || 528 MB/sec || 400 MB/sec || 85 MHz ||
 * PCIe x1 || 250 MB/sec || 190 MB/sec || 85 MHz ||
 * PCIe x4 || 1 GB/sec || 700 MB/sec || 85 MHz ||
 * PCIe x8 || 1.4 GB/sec || 850 MB/sec || 85 MHz ||

To begin the search I started with this list of [|sample framegrabbers]. The list is kind of old, so I added more to it, though most of the main players are on the list. Of note, there are a number of entries for a manufacturer called "Coreco". They have been bought out by Teledyne/DALSA and are listed there, accordingly. Also of note, the entry from "IO Industries" is no longer available. IO Industries is still around, though they only sell digital video editing hardware systems, not individual Camera Link cards.

||  ||   ||   ||   ||   ||
 * Vendor || Model || Bus || Price || Linux || Notes ||
 * Active Silicon ||  ||   ||   ||   ||   ||
 * || PHX-D24CL || PCI 32 ||  || yes, addl cost ||   ||
 * ||  || PCIe x1 ||   || yes, addl cost ||   ||
 * || PHX-D48CL || PCI 64 ||  || yes, addl cost ||   ||
 * ||  || PCIe x1 ||   || yes, addl cost ||   ||
 * ||  || PCIe x4 ||   || yes, addl cost ||   ||
 * || PHX-D64CL || PCIe x8 ||  || yes, addl cost ||   ||
 * AdLink ||  ||   ||   ||   ||   ||
 * || PCIe-CPL64 || PCIe x4 ||  || no ||   ||
 * Arvoo ||  ||   ||   ||   || Netherlands-based ||
 * || orlando CL || PCIe x1 ||  || yes ||   ||
 * BitFlow ||  ||   ||   ||   ||   ||
 * || Neon-CLB || PCIe x4 ||  || no ||   ||
 * || Neon-CLD || PCIe x4 ||  || no ||   ||
 * Cognex ||  ||   ||   ||   ||   ||
 * || MVS 8601e || PCIe x4 ||  || no ||   ||
 * || MVS 8602e || PCIe x4 ||  || no ||   ||
 * EDT ||  ||   ||   ||   ||   ||
 * || PCI DV C-Link || PCI 32 || $895 || yes, free dwnld ||  ||
 * || PCIe4 DVa C-Link || PCIe x4 ||  || yes, free dwnld ||   ||
 * || PCIe8 DVa C-Link || PCIe x8 ||  || yes, free dwnld ||   ||
 * Eltec ||  ||   ||   ||   || Germany-based ||
 * || p3i_CL || PCI 32 ||  || yes ||   ||
 * EPIX ||  ||   ||   ||   ||   ||
 * || PIXCI CL1 || PCI 32 || $495 || yes, $495 ||  ||
 * || PIXCI CL2 || PCI 64 || $895 || yes, $495 ||  ||
 * || PIXCI EB1 || PCIe x1 || $445 || yes, $495 ||  ||
 * || PIXCI EB1P || PCIe x1 || $495 || yes, $495 || PoCL ||
 * || PIXCI EL1 || PCIe x1 || $645 || yes, $495 ||  ||
 * || PIXCI EL1DB || PCIe x1 || $695 || yes, $495 ||  ||
 * || PIXCI E4 || PCIe x4 || $1295 || yes, $495 ||  ||
 * || PIXCI E4DB || PCIe x4 || $1395 || yes, $495 ||  ||
 * || PIXCI E8 || PCIe x8 || $1295 || yes, $495 ||  ||
 * Euresys ||  ||   ||   ||   || Belgium-based ||
 * || GRABLINK Value || PCI 32 ||  || yes ||   ||
 * || GRABLINK Avenue || PCI 64 ||  || yes ||   ||
 * || GRABLINK Expert 2 || PCI 64 ||  || yes ||   ||
 * || GRABLINK Quickpack ColorScan || PCI 64 ||  || yes ||   ||
 * || GRABLINK Base || PCIe x1 ||  || yes ||   ||
 * || GRABLINK Express || PCIe x1 ||  || yes ||   ||
 * || GRABLINK Quickpack CFA PCIe || PCIe x4 ||  || yes ||   ||
 * || GRABLINK DualBase || PCIe x4 ||  || yes ||   ||
 * || GRABLINK Full || PCIe x4 ||  || yes ||   ||
 * || GRABLINK Full XR || PCIe x4 ||  || yes ||   ||
 * Imperx ||  ||   ||   ||   ||   ||
 * || VCE-CLPCIe02 || PCIe x1 ||  || no ||   ||
 * Matrix Vision ||  ||   ||   ||   || Germany-based ||
 * || mvGAMMA-CL || PCI 32 ||  || yes, free dwnld ||   ||
 * || mvTITAN-CL || PCI 32 ||  || yes, free dwnld ||   ||
 * || mvHYPERION-CLb || PCIe x1 ||  || yes, free dwnld ||   ||
 * || mvHYPERION-CLm || PCIe x4 ||  || yes, free dwnld ||   ||
 * || mvHYPERION-CLf || PCIe x4 ||  || yes, free dwnld ||   ||
 * Matrox ||  ||   ||   ||   ||   ||
 * || Solios XCL-B || PCI 64 ||  || yes || $789, used ||
 * || Solios eCL || PCIe x1 ||  || yes ||   ||
 * || Solios eV-CL || PCIe x4 ||  || yes ||   ||
 * || Radient eCL || PCIe x8 ||  || yes || 4 camera link inputs ||
 * Mikrotron ||  ||   ||   ||   || Germany-based ||
 * || INSPECTA-4C || PCI 32 ||  || no ||   ||
 * || INSPECTA 5 || PCI 64 ||  || no ||   ||
 * || INSPECTA-4Ce || PCIe x1 ||  || no ||   ||
 * National Instruments ||  ||   ||   ||   ||   ||
 * || PCI-1426 || PCI 32 || $999 || no ||  ||
 * || PCIe-1427 || PCIe x1 || $949 || no ||  ||
 * || PCIe-1430 || PCIe x4 || $1749 || no ||  ||
 * || PCIe-1429 || PCIe x4 || $2100 || no ||  ||
 * Silicon Software ||  ||   ||   ||   || Germany-based ||
 * || microEnable IV AS1-PoCL || PCIe x1 ||  || yes, included || PoCL ||
 * || microEnable IV AD1-CL || PCIe x1 ||  || yes, included ||   ||
 * || microEnable IV AD1-PoCL || PCIe x1 ||  || yes, included || PoCL ||
 * || microEnable IV AD1-mPoCL || Pcie x1 ||  || yes, included || PoCL ||
 * || microEnable IV VD1-CL || PCIe x1 ||  || yes, included ||   ||
 * || microEnable IV VD4-CL || PCIe x4 ||  || yes, included ||   ||
 * || microEnable IV VD4-PoCL || PCIe x4 ||  || yes, included || PoCL ||
 * || microEnable IV AD4-CL || PCIe x4 ||  || yes, included ||   ||
 * || microEnable IV AD4-PoCL || PCIe x4 ||  || yes, included || PoCL ||
 * Teledyne/DALSA ||  ||   ||   ||   ||   ||
 * || PC2-CamLink || PCI 32 ||  || no || older literature ||
 * || X64-CL Full || PCI 64 ||  || no || refers to RedHat 9 ||
 * || X64-CL iPro || PCI 64 ||  || no || OS support, ||
 * || Xcelera-CL LX1 Base || PCIe x1 ||  || no || but nothing is ||
 * || X64-CL Express || PCIe x1 ||  || no || listed in the ||
 * || Xcelera-CL PX4 SE || PCIe x4 ||  || no || Teledyne DALSA ||
 * || Xcelera-CL PX4 Dual || PCIe x4 ||  || no || software page ||
 * || Xcelera-CL PX4 Full || PCIe x4 ||  || no ||   ||
 * || Xcelera-CL+ PX8 Full || PCIe x8 ||  || no ||   ||
 * || Xcelera-CL+ PX8 Dual || PCIe x8 ||  || no ||   ||

I would discourage purchase from any of the European-based vendors. I would also discourage getting a 64-bit PCI card (aka PCI-X) -- they're significantly more expensive, and we don't have a bus that can take advantage of it.

My recommendation would be the EPIX EB1 ([|see here]), it's only $445 for each board plus $495 for the 64-bit Linux driver (I assume we will only need to buy the Linux driver once). It's been consistently about half the cost of comparably capable cards from other manufacturers.