Conversion card and method to convert a general purpose personal computer into a dedicated mass storage appliance

A conversion card to convert a conventional general-purpose personal computer into a mass storage appliance dedicated to performing mass data storage functions defined by a mass storage operating system (MSOS), the personal computer having a host central processing unit (CPU) to which a local system bus and a primary expansion bus are connected, the primary expansion bus connecting to peripheral devices, the primary bus communicating signals between the host CPU and the peripheral devices connected to the primary bus, the peripheral devices including at least one disk drive mass storage device to which to read and write data, the personal computer also having a basic input output system (BIOS) which loads programs in response to boot probe signals delivered over the local system bus, the loaded programs operating the personal computer and the peripheral devices connected to the primary bus as the mass storage appliance, the conversion card comprising:

• a bus interface on the conversion card to connect the conversion card to the primary expansion bus and through which to communicate data with the conversion card;
• a solid-state memory card on the conversion card and containing nonvolatile code which defines the MSOS and which emulates a disk drive for purposes of booting the MSOS code in response to boot probe signals;
• a connector extending between the memory card and the local system bus to connect the memory card to respond to boot probe signals from the BIOS to identify the memory card as a disk drive and to transfer the MSOS code from the memory card through the connector to the local system bus to be booted and executed by the host CPU to establish mass storage functionality defined by the MSOS code;
• an intermediate memory on the conversion card to which to write data supplied by the host CPU and from which to read data to be written to the one mass storage disk drive device, the intermediate memory having a relatively lesser latency for read and write operations than the latency for read and write operations of each mass storage disk drive device;
• a bridge on the conversion card and connected between the interface connector and the intermediate memory to exchange signals defining the data between the intermediate memory and the primary bus;
• and
• a power source on the conversion card and connected to the intermediate memory to energize the intermediate memory to hold data written therein upon the occurrence of a predetermined error condition.

A method of converting a conventional general-purpose personal computer into a mass storage appliance dedicated to performing mass data storage functions defined by a mass storage operating system (MSOS), the personal computer having a primary expansion bus by which to connect peripheral devices and over which to communicate signals with the peripheral devices connected to the primary bus, the peripheral devices including at least one disk drive mass storage device to which to read and write data, the personal computer also having a basic input output system (BIOS) which loads programs in response to boot probe signals, the loaded programs operating the personal computer and the devices connected on the primary bus as the mass storage appliance, the conversion method comprising:

• recording code which defines the MSOS and which emulates a disk drive in a solid-state nonvolatile memory card;
• connecting the memory card to respond to boot probe signals from the BIOS to identify the memory card as a disk drive and to transfer the MSOS code from the memory card;
• booting the MSOS from the code transferred from the memory card to establish mass storage functionality defined by the MSOS code;
• writing data supplied from the primary bus to an intermediate memory;
• reading data from the intermediate memory and communicating the data read over the primary bus;
• writing the data read from the intermediate memory and communicated over the primary bus to the one mass storage disk drive device;
• selecting the intermediate memory to have a relatively lesser latency for read and write operations than the latency for read and write operations of each mass storage disk drive device;
• and
• energizing the intermediate memory to hold data written to the intermediate memory upon the incurrence of a predetermined error condition.

A general-purpose computer converted into a dedicated mass storage appliance, the general-purpose computer including a host central processing unit (CPU) and core circuitry connected to an expansion bus having at least one expansion slot, the core circuitry containing basic input output system (BIOS) code, the processor, core circuitry, expansion bus and expansion slot all contained within an enclosure of the general purpose computer, the general-purpose computer further comprising:

• solid-state, inherently nonvolatile memory card connected to a conversion card which is connected to an expansion slot of the expansion bus, the conversion card located within the enclosure,
• the memory card containing code which defines a mass storage operating system (MSOS) executable on the host CPU to perform mass data storage functions,
• the memory card emulating a mass storage disk drive device for booting purposes to permit the MSOS to be booted directly from the memory card in response to boot probe signals communicated from the BIOS over the expansion bus to the memory card,
• a mass storage adapter connected to the expansion bus,
• a plurality of mass storage disk drive devices connected to the mass storage adapter,
• an intermediate memory connected to the conversion card, the intermediate memory having lower latency than the latency of the mass storage disk drive devices,
• the host CPU writing data to the intermediate memory and reading data from the intermediate memory when executing the mass data storage functions established by the MSOS,
• the mass storage adapter writing data from the intermediate memory to the mass storage disk drive devices and reading data from the mass storage disk drive devices to the intermediate memory when the host CPU executes the mass data storage functions established by the MSOS, and
• the intermediate memory connected to a power source separate from a power supply for the general-purpose computer, the separate power source energizing the intermediate memory to hold data written therein upon the occurrence of a predetermined error condition.