| Hardware - Command and Control | SPSU - AUV 2005 |
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The Hardware for the Command and Control subsystem is the PC104 stack. The entire stack used in the AUVSI submarine is five PC104 cards. Three of these cards belong to the Command and Control subsystem. These cards are detailed below in the PC104 Cards section. The other two cards are custom cards. One of these cards is the Navigation board. The other is the custom Sonar card. All interfaces to and from the Command and Control system is handled from various input and outputs on the card stack.
The primary processing core of the AUVSI submarine is the processor card of the PC104 stack. Both the system processor and the program storage RAM are located on this card. There are a variety of interface connections between the processor card and the IO card, located directly above the processor card on the stack. In addition to this, the ISA bus origination connector is located on this card which sends the control signals to the various other system components as well as bringing the subsystem data back to the processor for use in the program code.
The processor card in the SPSU AUVSI submarine is an Athena ATH400-128N made by Diamond systems. The storage medium used on this card is a 250MB Flash RAM (part number FD-250-XT) also made by Diamond systems. The storage medium is linked to the processor card using a specialized socket and functions much the same as a hard drive functions in a normal PC microcomputer. The system software, documented in the Software sections of this subsystem and all of the other subsystems on this webpage, is installed on this card.
The Athena ATH400-128N processor card is displayed in the picture below:
There are three primary external interface components of the Athena processor card. The primary of these three is the ISA bus. The ISA bus is essentially the IBM PCXT and AT bus structure which has been modified for use in the PC104 architecture. It can be used in either an 8 bit or 16 bit processing mode but supplies much of the associated hardware required for specialized computing. Special drivers are required to interface this bus to the rest of the system and are used to bring some of the subsystem data to the processing card. This driver software is detailed on the Software section of this subsystem documentation.
In addition to the ISA bus connector there are two additional necessary output arrays needed for proper operation. One of these bus structures is the interface between the processor card and the IO card. This array, almost identical to a desktop PC microcomputer, provides the standard PC interfaces for serial and parallel ports, USB ports, the VGA monitor output and the other connectors housed on the IO card. The second interface is the VGA output, connected to the IO card using a ribbon cable.
The Input Output card provides the standard PC connections for use in PC104 operation. The Input Output card used by the SPSU AUVSI submarine is the Prometheus Panel Board (Part Number PNL-Z32). This card provides 2 USB ports, 4 serial COM ports, a single parallel port, keyboard, mouse and monitor output. An ethernet connection is also provided. Direct physical buttons for power and reset, as well as a power LED indicator and an input LED sensor, are also on board.
The Prometheus Panel Board (PNL-Z32) is displayed in the picture below:
The only interfaces to the IO card are the specialized connector to the processor card and an VGA input cable. Of note is that the IO card is the only PC104 card not connected the the ISA bus. All hardware functions needed for performance and operation are handled through the specialized connector.
The HE104 power supply is the primary power regulator and generator for the PC104 stack, analogous to a power supply in a standard desktop PC. This entire card consists of power regulation circuitry that takes the provide input voltage supply and converts it to the various power supply amounts needed in the different parts of the PC104 structure.
The HE104 card is displayed in the picture below:
The HE104 power supply card is interfaced to the rest of the PC104 stack through the ISA bus. In respect to the entire system, the ground and power points on each board derive their origin points from this board. The general input for power to the entire stack is located on this card, using a tabbed connector directly connected to the batteries used in the system.
The Flash RAM card, connected to the processor card and used for program storage, is the FD-250-XT. This card provides 250MB of hard storage location and is mounted inside of the Linux operating system as the primary hard drive. It contains the operating system, Java platform and the submarine operation code. It can be accessed in a variety of ways but is primarily manipulated through the ethernet connection on the IO card.
The Flash RAM card is pictured below:
The Flash RAM card interfaces to the Athena ATH400-128N processor card through an onboard socket. It is through this interface that the Flash RAM card is accessed from the processor on the processor card.