GOC4 Theory

The DARC2 outlined in this specification consists only of what is commonly referred to as a rack-mount computer. The supplied DARC2 will include a supplier hardware diagnostic CD, but will not include external peripherals such as keyboard, mouse, display monitor(s), or external cables. These external and peripheral functions will be provided by GE Healthcare unless agreed to and reflected in the respective part numbers. Agreements and system part numbers may also include the integration of GE Healthcare specified components into the DARC2, which will be outlined in this document and reflected in the respective part numbers. As an FDA governed and ISO compliant medical products OEM, controlled and documented configurations are of critical importance to GE Healthcare.

The requirements below are purposely specific to prevent supplier changes without advance notice and possible pre-qualification by GE Healthcare.

The DARC2 motherboard shall be an Intel^® Westville™, or equivalent, and shall meet the following requirements:

• Support Dual Intel^® Xeon™ Socket604 processors (2.8GHz minimum)

• Onboard regulation of processor voltages

• Intel^® E750x chipset

• 533Mhz Front Side Bus (FSB)

• Minimum of two (2) 10/100/1000 Mb onboard Ethernet ports

• 2.0GB DDR-266 SDRAM^® memory using minimum two (2) 184-pin DIMM sockets

• Support Serial Over LAN (SOLAN)

• One (1) ATA100 interface

• One (1) UART, DB9 interface

• One (1) Serial, DB9 (male) interface

• One (1) Ultra320 SCSI controller capable of supporting externally connected peripherals

• Minimum of four (4) PCI-X expansion slots (100Mhz min.)

• BIOS configuration is specified in Appendix A - BIOS Configuration

The DARC2 shall include at least four (4) PCI-X expansion slots.

• Two (2) slots shall be able to accommodate full-height “short” cards

• One slot shall accommodate one of the following DAS Interface Processor (DIP) cards

• One slot shall accommodate a DB9 male serial port

• Any remaining slots shall be able to accommodate low-profile or “half height” cards

The DARC2 shall include external switches and indicators on the chassis as follows:

• A pushbutton system POWER ON/OFF switch, which toggles system power ON or OFF when pressed or held.

• A pushbutton system RESET switch, accessible on the front of the chassis, that re-initializes all internal hardware without cycling power to the DARC2 (hard reset/soft boot).

• LED indicators shall be accessible and visible on the front of the chassis as follows:

  • System power is ON - steady GREEN - labeled “I/O” or “Power”

  • System error - flashing or steady RED - labeled “FLT”

  • LAN Activity - flashing Yellow - labeled “LAN”

  • Hard Disk Activity - flashing GREEN - labeled “HDD”

The Image Generator (IG) outlined in this specification consists only of what is commonly referred to as the computer. The supplied IG will not include external peripherals such as keyboard, mouse, display monitor(s), or external cables. These external and peripheral functions will be provided by GE Healthcare unless agreed to and reflected in the respective part numbers. Agreements and system part numbers may also include the integration of GE Healthcare specified components into the IG which will be outlined in this document and reflected in the respective part numbers. As an FDA governed and ISO compliant medical products OEM, controlled and documented configurations are of critical importance to GE Healthcare. The requirements below are purposely specific to prevent supplier changes without advance notice and possible pre-qualification by GE Healthcare.

The IG motherboard shall be an Intel^® Westville™, or equivalent, and shall meet the following requirements:

• Support Dual Intel^® Xeon™ Socket604 processors (2.8GHz minimum)

• Onboard regulation of processor voltages

• Intel^® E750x chipset

• 533Mhz Front Side Bus (FSB)

• Minimum of one (1) 10/100/1000 Mb onboard ethernet port

• 2.0GB DDR-266 SDRAM^® memory using minimum two (2) 184-pin DIMM sockets

• Support Serial Over LAN (SOLAN)

• One (1) PCI-X expansion slot (100Mhz min.) accommodating a riser card

• BIOS configuration shall be in accordance with details outlined in Appendix A of direction 2362872PSP

The IG shall include at least one (1) PCI-X expansion slot capable of accommodating a full-height “short” card.

This expansion slot shall contain a Recon Accelerator Card (GE Healthcare part no. 2316826).

The IG shall contain one (1) internal 3.5”, half-height, 1.44MB floppy diskette drive.

The IG does not require Ethernet ports in addition to the board-resident port.

• Chassis type: Rack-mountable

• Mounting orientation: Horizontal

• Maximum chassis height: 1U (44.5mm/1.75”)

• Maximum chassis width: 19” Rack standard

• Maximum chassis depth: 508mm (20”)

• Maximum weight: 10 Kg (22 lbs)

• Internal signal and power harness drops must be sufficient to support maximum configuration above

• Handles shall be mounted at each side of the front of the chassis for ease of removal from a rack. Handles shall protrude no more than 20mm (3/4”) from the chassis front panel.

The IG shall include external switches and indicators on the chassis as follows:

• A system pushbutton POWER ON/OFF switch which toggles system power ON or OFF when pressed or held.

• A pushbutton system RESET switch accessible on the front of the chassis that re-initializes all internal hardware without cycling power to the IG (hard reset/soft boot).

• LED indicators shall be accessible and visible on the front of the chassis as follows:

  • System power is ON - steady GREEN - labeled “I/O”

  • System error - flashing or steady RED - labeled “FLT”

  • LAN Activity - flashing GREEN - labeled “LAN”

2362872 IG as defined herein including:

• Dual Intel^® Xeon™ 2.8Ghz processors, 512KB L2 Cache, 2.0GB DDR200 SDRAM memory, etc.

• 2316826 Recon Accelerator Card (RAC).

The Global Operator Console 4th version (GOC4) consists of the following four (4) components.

• The Data Acquisition and Recon Control2 (DARC2) Component - incorporates the Scan Data Disk Array (SDDA) component from the previous console GRE/GOC3.

• The Image Generator (IG) Component - Is the same as the previous console version GRE/GOC3.

• Intercom Component - Is now a standalone component removed from the GRE/GOC4 SDDA and redesigned for better reliability and volume control.

• Cooling Package, including:

  • Fans

  • Front and Rear Covers with Foam Insulation

  • Air Filter

The DARC2 node receives raw data from the Data Acquisition System (DAS) through an on-board Data Interface processor (DIP) card, and stores that data in the Scan Data Disks located in the DARC2. The raw data is then delivered from the scan data disks in the DARC2 to the IG nodes. The IG nodes then create images using on-board processors and Recon Accelerator Cards (RAC). The images generated by the IG nodes are sent back to the DARC2 node, which gathers the images and sends them to the Host Computer.

Though each IG node will have a floppy boot disk, the DARC2 node should be capable of booting all IG nodes in the GOC4 via Gigabit Ethernet, using Serial Over LAN (SOLAN) functionality.

The host computer for the GOC4 console will be an off-the-shelf, Linux-based system, which meets EMC requirements per CISPR 11.

The DARC2 node provides to the IG nodes not only boot code but all application code and parameters as well.

Key goals of the GOC4 are:

• Scalability - performance and cost are scalable

• Flexibility - new functions and features such as cone-beam back projection should be easy to implement

• Performance - the high-end configuration should support 12 frames per second 2D back projection

• Ability to Upgrade - it should be relatively easy to replace installed-base consoles

• Performance - general purpose processors should be used to take advantage of improving processor speeds in the industry

The overall performance scope of the GOC4 shall be as follows:

• Recon times: 4fps - 12fps @ 2D BP

• Latency: < 2.0 seconds

• Image Matrix: < 512 x 512 pixels

• 2D BP: hardware and software support

• 3D BP: not yet supported

The DARC2 node controls most of the GOC4 functions and data flow, the exception being actual image generation. This node should receive a reconstruction request from the host computer, recognize the recon mode, timing, parameters, and data, and be able to generate the image set.

The raw data is first restored from the disks. The DARC2 node then creates an image set and requests image generation from the IG node.

While most of the software components (e.g. Recon_Control, Data_Restore, Image_Buffer, and Data_Acq) reside on this node, the components related to image generation are calculated on the IG nodes. The DARC2 node may help with some light calculation tasks such as offset vector generation.

Main data flow of the DARC2 node is described as follows:

• Receive raw data from the Gantry

• Store the raw data to the scan data disks

• Restore the raw data from the scan data disks and transfer to IG nodes over GB Ethernet

• Take multi-image streams from the IG nodes and forward them through a single image stream to the host computer

The control flow is described more fully in the GRE Design Theory of Operation.

The DARC2 node is comprised of the following:

• DARC2 computer: a computer node using a high-performance PC server

• DARC2 disk: the OS and Recon Applications software are stored on this disk

• DIP card: the DAS Interface Processor card

• Gigabit Ethernet (GbE) card: to increase IG nodes additional GbE cards may be installed

• CD-ROM drive: will be used for software installation and stand-alone use

• Floppy drive: a 3½” floppy drive will be used for BIOS flash, if necessary

The DARC2 node is intended to be a highly independent module, which can be replaced with PC servers consisting of the same specifications, regardless of manufacturer or manufacturer location.

The Image Generator (IG) component mounts an FPGA accelerator card (RAC card) on a PCI-X slot. The IG node works under the DARC2's supervision as a very high performance image generation calculator. When an IG node receives an image generation request from the DARC2 it will perform image generation processes. (i.e. preprocess, filtered back projection and post process, etc.) When an image set is calculated, the IG node notifies the DARC2 and transfers the set of pixel image data to the DARC2 via Gigabit Ethernet. Because each IG node is connected to the DARC2 node directly, without a switching hub, the individual IG nodes do not communicate with each other nor do they share processing data.

The GOC4 may consist of several IG nodes of varying performance. For example, one node may be replaced by a later version IG node having higher frequency CPUs. The GOC4 hardware allows any combination of server performance among the IG nodes. Therefore, all IG nodes and DARC2 nodes have to respond to a hardware configuration inquiry.

The IG node consists of the following:

• IG computer: computer using a high-performance PC server

• RAC Card: Recon Accelerator Card plugged into a PCI-X slot in the IG computer

• Floppy drive: a 3½” floppy drive will be used for BIOS flash, if necessary

The IG computer will be identical to the DARC2 computer as described in DARC2 (DARC2 Computer) above with the following exceptions:

• Chassis size: 19" rack-mount type EIA 1U height x 20" max depth

• DVD-ROM Drive: the IG computer will not have a DVD-ROM drive

This “low-profile” PCI card accelerates the two-dimensional (2D) back-projection process of the GOC4 and is plugged into a 64bit, 66MHz (533MB/sec) PCI-X slot on the IG node.

This parallel beam back-projector provides the GOC4 the ability to off-load the back-projection application from general-purpose processors to fully programmable hardware. This option dramatically increases the reconstruction performance per cost ratio.

Following are the high-level CTQs for the RAC card:

• Perform 2D parallel beam back-projection at >6fps

• PCI-X low-profile compatible

• Communicate with IG computer through a go => complete protocol

• Support PCI and Mailbox interrupts

• Reconstruct any image matrix size up to 524,288 32bit pixels

• In-system programmable FPGA design via software download

The major elements of the RAC card consist of:

• Field Programmable Gate Array (FPGA)

• QDR™ SRAM - creates two blocks of memory

• FLASH Memory - contains the FPGA's configuration code

The DARC2, IG, nodes are each powered by an AC switching power supply internal to each chassis. Each node receives its AC power from a 120Vac single-phase outlet box internal to the console chassis.

A redundant power supply and/or UPS option does not need to be supported by each node. The NGPDU will provide 120Vac to the operator's console. The switching power supply internal to each node is required to allow ±5% stability.

These AC switching power supply in each node shall be SSI EPS12V, SSI EPS1U, SSI EPS2U, or ATX compliant.

• SSI EPS12V: 24-pin for motherboard, 8-pin +12V for processor, 4-pin for peripherals

• SSI EPS1U: 62-pin edge finger for 1U chassis server

• SSI EPS2U: 24-pin for motherboard, 8-pin +12V for processor, 4-pin for peripherals

• ATX: standard PC power supply, 20-pin for motherboard, 4-pin for peripherals

The table below lists the node, power supply wattage, input port (max current), and output port.

A minimum of five outlets should be available for the GRE, excluding the host computer. Total AC power consumed by the GRE (excluding host computer and peripheral devices) is estimated below. This estimation assumes typical wattage while the IGs are calculating images.

• DARC2 + one (1) IG node ~ 700 W

• DARC2 + two (2) IG nodes ~ 1000 W

• DARC2 + three (3) IG nodes ~ 1300 W

The current SRU VME chassis requires a total of ~600W it is recommended that the operator console's total power requirements be calculated based upon a configuration utilizing three (3) IG nodes.

The intercom block has an audio amplifier circuit, enabling communication between the console operator and the patient on the table. This block also has sound source switching functionality.

The sound sources are:

• Console microphone on the SCIM (Operator's voice)

• Gantry microphone output (Patient's voice)

• Auto-voice L and R (output from the host computer)

These sound sources are multiplexed by the TALK button on the SCIM and by the Auto-voice output itself. The selected output signal goes to the following devices, based on prioritized logic.

• Table speaker

• Console speaker on the SCIM

• Auto-voice recording input on the host computer

  Also refer to GOC4 Intercom Theory and Adjustments.

The cooling package consists of three (3) components:

• Fan Assembly

• Front and Rear Covers, with Foam, for sound reduction and air flow control

• Air Filter

The Fan Assembly has perpendicular mounted larger fans than the GOC3 consoles. The Individual Fans are FRUs.

The Front and Rear covers are redesigned to accommodate the larger rear Fans, and are equipped with Insulating Foam, to both deaden noise and direct air flow for proper cooling.

The Air Filter is designed to capture room contaminates. It needs to be periodically cleaned (during a regular PM cycle).

The following diagrams illustrate the Cooling Package Components.

Figure 3. GOC4 Cooling Fans

Figure 4. GOC4 Rear Cover, with Foam

The GOC41.0 supports two types of diagnostic, power-on test and offline test. The power-on test is a subset of offline test. This test sweeps devices condition and checks the motherboard and some devices BIST results at system power-on after OS booted. The offline test checks each device condition, interface, and environment more strictly. The GOC41.0 should recover most of diagnostic condition without whole sub-system reset except motherboard diagnostic.

The GOC41.0 supports some kind of diagnostic tools.

• Motherboard diagnostics, including memory test

• DIP diagnostic

• RAC BIST and/or diagnostic

• Scan Data Disk diagnostic (On the DARC2)

• Network / connectivity test

Assemblies are assigned as FRUs based on the likelihood of need for replacement and fixed-right- first-time (FRFT). The following is a breakdown of GOC4 FRUs:

• DA/RC2 node

• DIP Board

• IG node

• RAC Card

• ICPT Board

• Host Computer

A diagnostic tool must identify the error unit as FRU level.

The diagnostic tool supports system inquiry capability. These are some examples of inquiry items, CPU frequency, Memory capacity, Disk configuration, number of IG, etc.