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93-699: ARINC was formerly headquartered in Annapolis, Maryland , and had two regional headquarters in London , established in 1999 to serve the Europe, Middle East, and Africa region, and Singapore , established in 2003 for the Asia Pacific region. ARINC had more than 3,200 employees at over 120 locations worldwide. The sale of the company by Carlyle Group to Rockwell Collins was completed on December 23, 2013, and from November 2018 onward operates as part of Collins Aerospace . ARINC

186-418: A processor or DMA -enabled device needs to read or write to a memory location, it specifies that memory location on the address bus (the value to be read or written is sent on the data bus). The width of the address bus determines the amount of memory a system can address. For example, a system with a 32-bit address bus can address 2 (4,294,967,296) memory locations. If each memory location holds one byte,

279-726: A bidirectional data bus, re-using the same wires for input and output at different times. Some processors use a dedicated wire for each bit of the address bus, data bus, and the control bus. For example, the 64-pin STEbus is composed of 8 physical wires dedicated to the 8-bit data bus, 20 physical wires dedicated to the 20-bit address bus, 21 physical wires dedicated to the control bus, and 15 physical wires dedicated to various power buses. Bus multiplexing requires fewer wires, which reduces costs in many early microprocessors and DRAM chips. One common multiplexing scheme, address multiplexing , has already been mentioned. Another multiplexing scheme re-uses

372-726: A card plugged into the bus, which is why computers have so many slots on the bus. But through the 1980s and 1990s, new systems like SCSI and IDE were introduced to serve this need, leaving most slots in modern systems empty. Today there are likely to be about five different buses in the typical machine, supporting various devices. "Third generation" buses have been emerging into the market since about 2001, including HyperTransport and InfiniBand . They also tend to be very flexible in terms of their physical connections, allowing them to be used both as internal buses, as well as connecting different machines together. This can lead to complex problems when trying to service different requests, so much of

465-510: A multiplexed address scheme, the address is sent in two equal parts on alternate bus cycles. This halves the number of address bus signals required to connect to the memory. For example, a 32-bit address bus can be implemented by using 16 lines and sending the first half of the memory address, immediately followed by the second half memory address. Typically two additional pins in the control bus – row-address strobe (RAS) and column-address strobe (CAS) – are used to tell

558-509: A passive backplane connected directly or through buffer amplifiers to the pins of the CPU . Memory and other devices would be added to the bus using the same address and data pins as the CPU itself used, connected in parallel. Communication was controlled by the CPU, which read and wrote data from the devices as if they are blocks of memory, using the same instructions, all timed by a central clock controlling

651-506: A serial bus inherently has no timing skew or crosstalk. USB , FireWire , and Serial ATA are examples of this. Multidrop connections do not work well for fast serial buses, so most modern serial buses use daisy-chain or hub designs. The transition from parallel to serial buses was allowed by Moore's law which allowed for the incorporation of SerDes in integrated circuits which are used in computers. Network connections such as Ethernet are not generally regarded as buses, although

744-446: A single source LRI/LRU or, as with ARINC 629, MIL-STD-1553B, and STANAG 3910, be duplex , allow all the connected LRI/LRUs to act, at different times ( half duplex ), as transmitters and receivers of data. The frequency or the speed of a bus is measured in Hz such as MHz and determines how many clock cycles there are per second; there can be one or more data transfers per clock cycle. If there

837-433: A unified system bus . In this case, a single mechanical and electrical system can be used to connect together many of the system components, or in some cases, all of them. Later computer programs began to share memory common to several CPUs. Access to this memory bus had to be prioritized, as well. The simple way to prioritize interrupts or bus access was with a daisy chain . In this case signals will naturally flow through

930-619: Is "the best single portrait of men and manners, of rural and urban life, of the wide range of society and scenery in colonial America." Annapolis became the temporary capital of the United States after the signing of the Treaty of Paris in 1783. Congress was in session in the state house from November 26, 1783, to August 19, 1784, and it was in Annapolis on December 23, 1783, that General Washington resigned his commission as commander-in-chief of

1023-406: Is a communication system that transfers data between components inside a computer , or between computers. This expression covers all related hardware components (wire, optical fiber , etc.) and software , including communication protocols . In most traditional computer architectures , the CPU and main memory tend to be tightly coupled, with the internal bus connecting the two being known as

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1116-412: Is a single transfer per clock cycle it is known as Single Data Rate (SDR), and if there are two transfers per clock cycle it is known as Double Data Rate (DDR) although the use of signalling other than SDR is uncommon outside of RAM. An example of this is PCIe which uses SDR. Within each data transfer there can be multiple bits of data. This is described as the width of a bus which is the number of bits

1209-628: Is adjacent to the city limits. A settlement in the Province of Maryland named "Providence" was founded on the north shore of the Severn River on the middle Western Shore of the Chesapeake Bay in 1649 by Puritan exiles from the Province/Dominion of Virginia led by the third Proprietary Governor of Maryland , William Stone (1603–1660). The settlers later moved to a better-protected harbor on

1302-699: Is land and 0.92 square miles (2.38 km ) is water. Annapolis lies within the humid subtropical climate zone ( Köppen Cfa ), with hot, humid summers, cool winters, and generous precipitation year-round. Low elevation and proximity to the Chesapeake Bay give the area more moderate spring and summertime temperatures and slightly less extreme winter lows than locations further inland, such as Washington, D.C. See or edit raw graph data . In November 2020, NASA reported that Annapolis had 18 days of high-tide (non-storm-related) flooding from May 2019 to April 2020, an increase over 2018's 12 days, and higher than

1395-475: Is provided by the bus‍—‌is not the case in many avionic systems , where data connections such as ARINC 429 , ARINC 629 , MIL-STD-1553B (STANAG 3838), and EFABus ( STANAG 3910 ) are commonly referred to as “data buses” or, sometimes, "databuses". Such avionic data buses are usually characterized by having several equipments or Line Replaceable Items/Units (LRI/LRUs) connected to a common, shared media . They may, as with ARINC 429, be simplex , i.e. have

1488-543: Is the capital of the U.S. state of Maryland . It is the county seat of Anne Arundel County and its only incorporated city. Situated on the Chesapeake Bay at the mouth of the Severn River , 25 miles (40 km) south of Baltimore and about 30 miles (50 km) east of Washington, D.C. , Annapolis forms part of the Baltimore–Washington metropolitan area . The 2020 census recorded its population as 40,812, an increase of 6.3% since 2010. This city served as

1581-436: Is the case with PCI . While the term " peripheral bus " is sometimes used to refer to all other buses apart from the system bus, the "expansion bus" has also been used to describe a third category of buses separate from the peripheral bus, which includes bus systems like PCI. Early computer buses were parallel electrical wires with multiple hardware connections, but the term is now used for any physical arrangement that provides

1674-681: The American Revolutionary War , with Great Britain recognizing the independence of the United States. The city and state capitol was also the site of the 1786 Annapolis Convention , which issued a call to the states to send delegates for the Constitutional Convention to be held the following year in Philadelphia . The Annapolis Peace Conference took place in 2007. Annapolis is the home of St. John's College , founded 1696. The United States Naval Academy , established 1845,

1767-654: The Boeing 727 , Douglas DC-9 , DC-10 , Boeing 737 and 747 , and Airbus A300 . The 600 Series are reference standards for avionics equipment specified by the ARINC 700 Series The 700 Series describes the form, fit, and function of avionics equipment installed predominately on transport category aircraft. The 800 Series comprises a set of aviation standards for aircraft, including fiber optics used in high-speed data buses . Annapolis, Maryland Annapolis ( / ə ˈ n æ p əl ɪ s / ə- NAP -əl-iss )

1860-469: The IBM PC , although similar physical architecture can be employed, instructions to access peripherals ( in and out ) and memory ( mov and others) have not been made uniform at all, and still generate distinct CPU signals, that could be used to implement a separate I/O bus. These simple bus systems had a serious drawback when used for general-purpose computers. All the equipment on the bus had to talk at

1953-724: The Potomac River in Virginia. Per orders from Lord Baltimore, Stone returned the following spring at the head of a Cavalier royalist force, loyal to the uncrowned King of England . On March 25, 1655, in what became known as the Battle of the Severn (the first colonial naval battle in North America ), Stone was defeated, taken prisoner, and replaced by Lt. Gen. Josias Fendall (1628–1687) as fifth Proprietary Governor . Fendall governed Maryland during

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2046-876: The S-100 bus were used, but to reduce latency , modern memory buses are designed to connect directly to DRAM chips, and thus are designed by chip standards bodies such as JEDEC . Examples are the various generations of SDRAM , and serial point-to-point buses like SLDRAM and RDRAM . An exception is the Fully Buffered DIMM which, despite being carefully designed to minimize the effect, has been criticized for its higher latency. Buses can be parallel buses , which carry data words in parallel on multiple wires, or serial buses , which carry data in bit-serial form. The addition of extra power and control connections, differential drivers , and data connections in each direction usually means that most serial buses have more conductors than

2139-484: The SATA ports in modern computers support multiple peripherals, allowing multiple hard drives to be connected without an expansion card . In systems that have a similar architecture to multicomputers , but which communicate by buses instead of networks, the system bus is known as a front-side bus . In such systems, the expansion bus may not share any architecture with their host CPUs, instead supporting many different CPUs, as

2232-544: The Severn River . Students that attend the Naval Academy are enrolled for four years with a following five year commitment to serving on active duty in the Marine Corps or Navy. Students hold the naval rank of Midshipman , and on average about 4,500 are enrolled. St. John's College is a non-sectarian private college that was once supported by the state. It was opened in 1789 as the successor of King William's School, which

2325-536: The Treaty of Paris was ratified there on January 14, 1784, so Annapolis became the first peacetime capital of the U.S. It was in the Maryland State House that George Washington famously resigned his commission before the Continental Congress on December 23, 1783. The United States Naval Academy was founded in 1845 on the site of Fort Severn , and now occupies an area of land reclaimed from

2418-446: The system bus . In systems that include a cache , CPUs use high-performance system buses that operate at speeds greater than memory to communicate with memory. The internal bus (also known as the internal data bus, memory bus or system bus ) connects internal components of a computer to the mother board. Local buses connect the CPU and memory to the expansion bus , which in turn connects the computer to peripherals. Bus systems such as

2511-426: The 1995-2005 average of 2 days annually. The increase is attributed to sea level rise caused by climate change . Resultant flood damages caused local businesses to lose as much as $ 172,000 a year. On Naval Academy grounds, seawater came out of storm drains, with McNair Road and Ramsay Road flooding 20 times in 2020 and more than 40 times each in 2018 and 2019. Adaptation approaches such as sea walls and building up

2604-488: The Airlines Electronic Engineering Committee (AEEC) where aviation suppliers such as Collins Aerospace and GE Aviation serve as contributors in support of their airline customer base. An abbreviated list follows. The 400 Series describes guidelines for installation, wiring, data buses , and databases. The 500 Series describes older analog avionics equipment used on early jet aircraft such as

2697-553: The Colonial Players theater in 1981. Based on the play by Charles Dickens , the 90-minute production by the Colonial Players is an original musical adaptation, with play and lyrics by Richard Wade and music by Dick Gessner. Colonial Players, Inc. is a nonprofit organization founded in 1949. Its first production, The Male Animal , was performed in 1949 at the Annapolis Recreation Center on Compromise Street. In 1955,

2790-548: The Continental Army. For the 1783 Congress, the Governor of Maryland commissioned John Shaw , a local cabinetmaker, to create an American flag . Shaw's flag is slightly different from other designs of the time: the blue field extends over the entire height of the hoist. Shaw developed two versions of the flag: one which started with a red stripe and another that started with a white one. In 1786, delegates from all states of

2883-465: The DRAM whether the address bus is currently sending the first half of the memory address or the second half. Accessing an individual byte frequently requires reading or writing the full bus width (a word ) at once. In these instances the least significant bits of the address bus may not even be implemented - it is instead the responsibility of the controlling device to isolate the individual byte required from

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2976-468: The IEEE "Superbus" study group, the open microprocessor initiative (OMI), the open microsystems initiative (OMI), the "Gang of Nine" that developed EISA , etc. Early computer buses were bundles of wire that attached computer memory and peripherals. Anecdotally termed the " digit trunk " in the early Australian CSIRAC computer, they were named after electrical power buses, or busbars . Almost always, there

3069-680: The Korean and Vietnam wars. It was at Annapolis in July 1940 that Grand Duchess Charlotte of Luxembourg arrived in exile during World War II. In the summer of 1984, the Navy Marine Corps Memorial Stadium in Annapolis hosted soccer games as part of the XXIII Olympiad . During September 18–19, 2003, Hurricane Isabel created the largest storm surge known in Annapolis's history, cresting at 7.58 feet (2.31 m). Much of downtown Annapolis

3162-575: The SAE Industry Technologies Consortia (SAE ITC). United Technologies completed its acquisition of Rockwell Collins in November 2018 and merged it with its UTC Aerospace Systems to form Collins Aerospace . Though known for publishing "ARINC Standards", this role is independent of ARINC commercial activities. ARINC Industry Activities involve three aviation committees: ARINC services include: The ARINC Standards are prepared by

3255-556: The Severn's southern shore. The settlement on the south shore, known from 1683 as "Town at Proctor's", then "Town at the Severn", became in 1694 "Anne Arundel's Towne" (after Lady Ann Arundell (1616–1649), the late wife of the late Cecilius Calvert, second Lord Baltimore , 1605–1675). In 1654, after the Third English Civil War , Parliamentary forces assumed control of the Maryland colony and Stone went into exile south across

3348-603: The Union were invited to meet in Annapolis to consider measures for the better regulation of commerce. Delegates from only five states—New York, Pennsylvania, Virginia, New Jersey, and Delaware—actually attended the September 1786 gathering, known afterward as the Annapolis Convention . Without proceeding to the business for which they had met, the delegates passed a resolution calling for another convention to meet at Philadelphia in

3441-492: The academy's English curriculum. The King William Players, a student theater group at St. John's College , holds two performances each semester in the college's Francis Scott Key Auditorium. Admission is usually free and open to the public. The Banneker-Douglass Museum , located in the historic Mount Moriah Church at 87 Franklin Street, documents the history of African Americans in Maryland. Since its opening on February 24, 1984,

3534-533: The address bus pins as the data bus pins, an approach used by conventional PCI and the 8086 . The various "serial buses" can be seen as the ultimate limit of multiplexing, sending each of the address bits and each of the data bits, one at a time, through a single pin (or a single differential pair). Over time, several groups of people worked on various computer bus standards, including the IEEE Bus Architecture Standards Committee (BASC),

3627-469: The addressable memory space is 4 GB. Early processors used a wire for each bit of the address width. For example, a 16-bit address bus had 16 physical wires making up the bus. As the buses became wider and lengthier, this approach became expensive in terms of the number of chip pins and board traces. Beginning with the Mostek 4096 DRAM , address multiplexing implemented with multiplexers became common. In

3720-411: The associated eSATA are one example of a system that would formerly be described as internal, while certain automotive applications use the primarily external IEEE 1394 in a fashion more similar to a system bus. Other examples, like InfiniBand and I²C were designed from the start to be used both internally and externally. An address bus is a bus that is used to specify a physical address . When

3813-489: The bits themselves, and allows for an increase in data transfer speed without increasing the frequency of the bus. The effective or real data transfer speed/rate may be lower due to the use of encoding that also allows for error correction such as 128/130b (b for bit) encoding. The data transfer speed is also known as the bandwidth. The simplest system bus has completely separate input data lines, output data lines, and address lines. To reduce cost, most microcomputers have

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3906-493: The bus can transfer per clock cycle and can be synonymous with the number of physical electrical conductors the bus has if each conductor transfers one bit at a time. The data rate in bits per second can be obtained by multiplying the number of bits per clock cycle times the frequency times the number of transfers per clock cycle. Alternatively a bus such as PCIe can use modulation or encoding such as PAM4 which groups 2 bits into symbols which are then transferred instead of

3999-409: The bus had to talk at the same speed. While the CPU was now isolated and could increase speed, CPUs and memory continued to increase in speed much faster than the buses they talked to. The result was that the bus speeds were now much slower than what a modern system needed, and the machines were left starved for data. A particularly common example of this problem was that video cards quickly outran even

4092-511: The bus in physical or logical order, eliminating the need for complex scheduling. Digital Equipment Corporation (DEC) further reduced cost for mass-produced minicomputers , and mapped peripherals into the memory bus, so that the input and output devices appeared to be memory locations. This was implemented in the Unibus of the PDP-11 around 1969. Early microcomputer bus systems were essentially

4185-615: The bus supplied power, but often use a separate power source. This distinction is exemplified by a telephone system with a connected modem , where the RJ11 connection and associated modulated signalling scheme is not considered a bus, and is analogous to an Ethernet connection. A phone line connection scheme is not considered to be a bus with respect to signals, but the Central Office uses buses with cross-bar switches for connections between phones. However, this distinction‍—‌that power

4278-482: The capital of the royal colony, the Province of Maryland , to Anne Arundel's Towne and renamed the town "Annapolis" after Princess Anne of Denmark and Norway , soon to become Queen Anne of Great Britain (1665–1714, reigned 1702–1714). Annapolis was incorporated as a city in 1708. Colonel John Seymour, the Governor of Maryland from 1704 to 1709, wrote Queen Anne on March 16, 1709, with qualifications for municipal officials and provisions for fairs and market days for

4371-431: The cards to be much more complex. These buses also often addressed speed issues by being "bigger" in terms of the size of the data path, moving from 8-bit parallel buses in the first generation, to 16 or 32-bit in the second, as well as adding software setup (now standardised as Plug-n-play ) to supplant or replace the jumpers. However, these newer systems shared one quality with their earlier cousins, in that everyone on

4464-522: The census of 2010, there were 38,394 people, 16,136 households, and 8,776 families residing in the city. The population density was 5,347.4 inhabitants per square mile (2,064.6/km ). There were 17,845 housing units at an average density of 2,485.4 units per square mile (959.6 units/km ). The racial makeup of the city was 60.1% White , 26.0% African American , 0.3% Native American , 2.1% Asian , 9.0% from other races , and 2.6% from two or more races. Hispanic or Latino people of any race were 16.8% of

4557-553: The city celebrated the 300th anniversary of its 1708 Royal Charter, which established democratic self-governance. The many cultural events of this celebration were organized by Annapolis Charter 300. Annapolis was home of the Anne Arundel County Battle of the Bands, which was held at Maryland Hall from 1999 to 2015. The event was a competition between musical groups from each high school in the county; it raised over $ 100,000 for

4650-552: The city is still referred to as Parole . The soldiers who did not survive were buried in the Annapolis National Cemetery . In 1900, Annapolis had a population of 8,585. On December 21, 1906, Henry Davis was lynched in the city. He was suspected of assaulting a local woman. Nobody was ever tried for the crime. During World War II , shipyards in Annapolis built a number of PT Boats, and military vessels such as minesweepers and patrol boats were built in Annapolis during

4743-430: The city was $ 49,243, and the median income for a family was $ 56,984 (these figures had risen to $ 70,140 and $ 84,573 respectively, according to a 2007 estimate ). Males had a median income of $ 39,548 versus $ 30,741 for females. The per capita income for the city was $ 27,180. About 9.5% of families and 12.7% of the population were living in poverty, of which 20.8% were under age 18 and 10.4% were age 65 or over. According to

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4836-416: The city's 2018 Comprehensive Annual Financial Report, the top employers in the city, excluding state and local government, are: Annapolis has a thriving community theater scene which includes two venues in the historic district. On East Street, Colonial Players produces approximately six shows a year in its 180-seat theater. A Christmas Carol has been a seasonal tradition in Annapolis since it opened at

4929-417: The city. The population density was 5,326.0 inhabitants per square mile (2,056.4/km ). There were 16,165 housing units at an average density of 2,402.3 units per square mile (927.5 units/km ). The racial makeup of the city was 62.66% White , 31.44% Black or African American , 0.17% Native American , 1.81% Asian , 0.03% Pacific Islander , 2.22% from other races, and 1.67% from two or more races. 8.42% of

5022-558: The commerce was considerable, but it declined rapidly after Baltimore, with its deeper harbor, was made a port of entry in 1780. Water trades such as oyster-packing, boatbuilding and sailmaking became the city's chief industries. Annapolis is home to a large number of recreational boats that have largely replaced the seafood industry in the city. Dr. Alexander Hamilton (1712–1756), a Scottish-born doctor and writer, lived and worked in Annapolis. Leo Lemay says his 1744 travel diary Gentleman's Progress: The Itinerarium of Dr. Alexander Hamilton

5115-788: The commercial aviation industry and U.S. military . ARINC also developed the standards for the trays and boxes used to hold standard line-replaceable units (like radios) in aircraft. This subsequently allowed electronics to be rapidly replaced without complex fasteners or test equipment. In 1978 ARINC introduced ACARS ( Aircraft Communications Addressing and Reporting System ), a datalink system that enables ground stations (airports, aircraft maintenance bases, etc.) to upload data (such as flight plans) and download data (such as fuel quantity, weight on wheels, flight management system (FMS) data), via an onboard Communications Management Unit (CMU). ARINC has expanded its business in aerospace and defense through its ARINC Engineering Services subsidiary . With

5208-520: The complete word transmitted. This is the case, for instance, with the VESA Local Bus which lacks the two least significant bits, limiting this bus to aligned 32-bit transfers. Historically, there were also some examples of computers which were only able to address words -- word machines . The memory bus is the bus which connects the main memory to the memory controller in computer systems . Originally, general-purpose buses like VMEbus and

5301-491: The computer into two "worlds", the CPU and memory on one side, and the various devices on the other. A bus controller accepted data from the CPU side to be moved to the peripherals side, thus shifting the communications protocol burden from the CPU itself. This allowed the CPU and memory side to evolve separately from the device bus, or just "bus". Devices on the bus could talk to each other with no CPU intervention. This led to much better "real world" performance, but also required

5394-460: The county's high school music programs during its 17-year run. On June 28, 2018, at the Capital Gazette , a gunman opened fire, killing five journalists and injuring two more. An EF-2 tornado struck the western edge of the city on September 1, 2021, during the remnants of Hurricane Ida . Homes, businesses, and restaurants had significant damage near Maryland Route 450 , where EF-2 damage

5487-548: The data directly in memory, a concept known as direct memory access . Low-performance bus systems have also been developed, such as the Universal Serial Bus (USB). Given technological changes, the classical terms "system", "expansion" and "peripheral" no longer have the same connotations. Other common categorization systems are based on the bus's primary role, connecting devices internally or externally. However, many common modern bus systems can be used for both. SATA and

5580-489: The difference is largely conceptual rather than practical. An attribute generally used to characterize a bus is that power is provided by the bus for the connected hardware. This emphasizes the busbar origins of bus architecture as supplying switched or distributed power. This excludes, as buses, schemes such as serial RS-232 , parallel Centronics , IEEE 1284 interfaces and Ethernet, since these devices also needed separate power supplies. Universal Serial Bus devices may use

5673-646: The following year to amend the Articles of Confederation . The resulting Philadelphia Convention drafted and approved the Constitution of the United States , which remains in force. On April 24, 1861, the midshipmen of the Naval Academy relocated their base in Annapolis and were temporarily housed in Newport, Rhode Island , until October 1865. In 1861, the first of three camps that were built for holding paroled soldiers

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5766-675: The former location of the Shaw Blacksmith Shop, in 1967, and became owner of the property in 1990. The Naval Academy Masqueraders, a theater group at the United States Naval Academy, produces one "main-stage show" each fall and student-directed one-act plays in the spring. Founded in 1847, the Masqueraders is the oldest extracurricular activity at the Naval Academy. Its shows, performed in Mahan Hall, are selected to support

5859-411: The height of roadways and athletic fields are predicted to last only a few decades. As of the census of 2020, there were 40,812 people. The racial makeup of the city was 49.4% Non-Hispanic White , 21.7% African American , 0.7% Native American , 2.5% Asian , 14.5% from other races , and 8.1% from two or more races. Hispanic or Latino residents of any race made up 22.9% of the population. As of

5952-632: The input and output of a given bus. IBM introduced these on the IBM 709 in 1958, and they became a common feature of their platforms. Other high-performance vendors like Control Data Corporation implemented similar designs. Generally, the channel controllers would do their best to run all of the bus operations internally, moving data when the CPU was known to be busy elsewhere if possible, and only using interrupts when necessary. This greatly reduced CPU load, and provided better overall system performance. To provide modularity, memory and I/O buses can be combined into

6045-632: The latter half of the English Commonwealth period. In 1660, he was replaced by Phillip Calvert (1626–1682) as fifth/sixth Governor of Maryland , after the restoration of Charles II (1630–1685) as King in England . In 1694, soon after the overthrow of the Catholic government of second Royal Governor Thomas Lawrence (1645–1714, in office for a few months in 1693), the third Royal Governor Francis Nicholson (1655-1727/28, in office: 1694–1698), moved

6138-446: The minimum of one used in 1-Wire and UNI/O . As data rates increase, the problems of timing skew , power consumption, electromagnetic interference and crosstalk across parallel buses become more and more difficult to circumvent. One partial solution to this problem has been to double pump the bus. Often, a serial bus can be operated at higher overall data rates than a parallel bus, despite having fewer electrical connections, because

6231-467: The museum has provided educational programs, rotating exhibits, and a research facility. Admission is free. Preble Hall , named for Edward Preble , houses the U.S. Naval Academy Museum, founded in 1845. Its Beverley R. Robinson Collection contains 6,000 prints depicting European and American naval history from 1514 through World War II. It is also home to one of the world's best ship model collections, donated by Henry Huttleston Rogers . Rogers's donation

6324-554: The national capital. In land area Annapolis (proper) is also the smallest of the United States capital cities . The city is a part of the Atlantic Coastal Plain, and is relatively flat, with the highest point being only 50 feet (15 m) above sea level. According to the United States Census Bureau , the city has a total area of 8.10 square miles (20.98 km ), of which 7.18 square miles (18.60 km )

6417-401: The newer bus systems like PCI , and computers began to include AGP just to drive the video card. By 2004 AGP was outgrown again by high-end video cards and other peripherals and has been replaced by the new PCI Express bus. An increasing number of external devices started employing their own bus systems as well. When disk drives were first introduced, they would be added to the machine with

6510-538: The organization moved to its venue in a former automotive repair shop on East Street. During the warmer months, Annapolis Summer Garden Theatre presents three shows on its outdoor stage, which is visible from the City Dock. A nonprofit organization, Annapolis Summer Garden Theatre has been providing "theatre under the stars" since 1966, when it performed You Can't Take It with You and Brigadoon at Carvel Hall Hotel. It began leasing its site at 143 Compromise Street,

6603-435: The population were Hispanic or Latino of any race. There were 15,303 households, out of which 24.5% had children under the age of 18 living with them, 36.6% were married couples living together, 16.3% had a female householder with no husband present, and 43.3% were non-families. Of all households, 32.9% were made up of individuals, and 9.2% had someone living alone who was 65 years of age or older. The average household size

6696-442: The population. There were 16,136 households, of which 26.6% had children under the age of 18 living with them, 35.3% were married couples living together, 14.9% had a female householder with no husband present, 4.2% had a male householder with no wife present, and 45.6% were non-families. Of all households, 35.0% were made up of individuals, and 11.1% had someone living alone who was 65 years of age or older. The average household size

6789-484: The program attempted to perform those other tasks, it might take too long for the program to check again, resulting in loss of data. Engineers thus arranged for the peripherals to interrupt the CPU. The interrupts had to be prioritized, because the CPU can only execute code for one peripheral at a time, and some devices are more time-critical than others. High-end systems introduced the idea of channel controllers , which were essentially small computers dedicated to handling

6882-543: The region. The conference was held at the United States Naval Academy on November 26, 2007. The Maryland State House is the oldest in continuous legislative use in the United States. Construction started in 1772, and the Maryland legislature first met there in 1779. It is topped by the largest wooden dome built without nails in the country. The Maryland State House housed the workings of the United States government from November 26, 1783, to August 13, 1784, and

6975-741: The sale of the company to Rockwell Collins, the ARINC Engineering Services subsidiary split into Commercial Aerospace and Defense Services. The Defense Services branch was then purchased by Booz Allen Hamilton , remaining part of the Carlyle group. The sale of a Standards Development Organization (SDP) to a corporate sponsor raised concerns of conflict of interest and resulted in the sale of the ARINC Industry Activities (IA) Division to SAE International in January 2014. It now operates under

7068-529: The same logical function as a parallel electrical busbar . Modern computer buses can use both parallel and bit serial connections, and can be wired in either a multidrop (electrical parallel) or daisy chain topology, or connected by switched hubs. Many modern CPUs also feature a second set of pins similar to those for communicating with memory—but able to operate with different speeds and protocols—to ensure that peripherals do not slow overall system performance. CPUs can also feature smart controllers to place

7161-420: The same speed, as it shared a single clock. Increasing the speed of the CPU becomes harder, because the speed of all the devices must increase as well. When it is not practical or economical to have all devices as fast as the CPU, the CPU must either enter a wait state , or work at a slower clock frequency temporarily, to talk to other devices in the computer. While acceptable in embedded systems , this problem

7254-645: The seat of the Confederation Congress , formerly the Second Continental Congress , and temporary national capital of the United States in 1783–1784. At that time, General George Washington came before the body convened in the new Maryland State House and resigned his commission as commander of the Continental Army . A month later, the Congress ratified the Treaty of Paris of 1783 , ending

7347-518: The speed of the CPU. Still, devices interrupted the CPU by signaling on separate CPU pins. For instance, a disk drive controller would signal the CPU that new data was ready to be read, at which point the CPU would move the data by reading the "memory location" that corresponded to the disk drive. Almost all early microcomputers were built in this fashion, starting with the S-100 bus in the Altair 8800 computer system. In some instances, most notably in

7440-480: The town. 17th-century Annapolis was little more than a village, but it grew rapidly for most of the 18th century until the American Revolutionary War as a political and administrative capital, a port of entry , and a major center of the Atlantic slave trade . The Maryland Gazette , which became an important weekly journal, was founded there by Jonas Green in 1745; in 1769 a theatre opened; during this period also

7533-522: The work on these systems concerns software design, as opposed to the hardware itself. In general, these third generation buses tend to look more like a network than the original concept of a bus, with a higher protocol overhead needed than early systems, while also allowing multiple devices to use the bus at once. Buses such as Wishbone have been developed by the open source hardware movement in an attempt to further remove legal and patent constraints from computer design. The Compute Express Link (CXL)

7626-403: Was 2.30 and the average family size was 2.93. In the city, 21.7% of the population was under the age of 18, 9.3% from 18 to 24, 33.4% from 25 to 44, 23.7% from 45 to 64, and 11.9% was 65 years of age or older. The median age was 36 years. For every 100 females, there were 90.0 males. For every 100 females age 18 and over there were 86.8 males age 18 and over. The median income for a household in

7719-434: Was 2.34 and the average family size was 3.02. The median age in the city was 36 years. 20.8% of residents were under the age of 18; 9.9% were between the ages of 18 and 24; 31.1% were from 25 to 44; 25.3% were from 45 to 64; and 13% were 65 years of age or older. The gender makeup of the city was 47.8% male and 52.2% female. As of the census of 2000, there were 35,838 people, 15,303 households, and 8,676 families residing in

7812-472: Was created on the campus of St. John's College . The second location of Camp Parole would house over 20,000 and would be located where Forest Drive is currently. The third and final location was finished in late 1863 and would be placed near the Elkridge Railroad, as to make transportation of soldiers and resources easier before and allowing the camp to grow to its highest numbers. This area just west of

7905-437: Was flooded and many businesses and homes in outlying areas were damaged. The previous record was 6.35 feet (1.94 m) during a hurricane in 1933, and 5.5 feet (1.7 m) during Hurricane Hazel in 1954. Downtown Annapolis has high-tide "sunny day" flooding. A Stanford University study found that this resulted in 3,000 less visits and $ 172,000 in lost revenue for local business in 2017. From mid-2007 through December 2008,

7998-472: Was founded by an act of the Maryland legislature in 1696 and was opened in 1701. Its principal building, McDowell Hall, was originally to be the governor's mansion; although £4,000 was appropriated to build it in 1742, it was not completed until after the War of Independence. Located 25 miles (40 km) south of Baltimore and 30 miles (48 km) east of Washington, D.C. , Annapolis is the closest state capital to

8091-543: Was incorporated in 1929 as Aeronautical Radio, Incorporated. It was chartered by the Federal Radio Commission (which later became the Federal Communications Commission ) in order to serve as the airline industry's single licensee and coordinator of radio communication outside of the government. The corporation's stock was held by four major airlines of the day. Through most of its history, ARINC

8184-441: Was not tolerated for long in general-purpose, user-expandable computers. Such bus systems are also difficult to configure when constructed from common off-the-shelf equipment. Typically each added expansion card requires many jumpers in order to set memory addresses, I/O addresses, interrupt priorities, and interrupt numbers. "Second generation" bus systems like NuBus addressed some of these problems. They typically separated

8277-511: Was observed with estimated winds of 125 mph. The tornado dissipated immediately past U.S. Route 50 and U.S. Route 301. As announced by United States Secretary of State Condoleezza Rice , Annapolis was the venue for a Middle East summit dealing with the Israeli–Palestinian peace process , with the participation of Israeli Prime Minister Ehud Olmert , Palestinian President Mahmoud Abbas (" Abu Mazen ") and various other leaders from

8370-402: Was one bus for memory, and one or more separate buses for peripherals. These were accessed by separate instructions, with completely different timings and protocols. One of the first complications was the use of interrupts . Early computer programs performed I/O by waiting in a loop for the peripheral to become ready. This was a waste of time for programs that had other tasks to do. Also, if

8463-502: Was owned by airlines and other aviation-related companies such as Boeing until the sale to The Carlyle Group in October 2007. Not much later ARINC took on the responsibility for all ground-based, aeronautical radio stations and for ensuring station compliance with Federal Radio Commission (FRC) rules and regulations. Using this as a base technology, ARINC expanded its contributions to transport communications as well as continuing to support

8556-497: Was purchased from St. John's College by the Hammond-Harwood House Association, it has served as a museum exhibiting a collection of John Shaw furniture and Charles Willson Peale paintings. Its exterior and interior preserve the original architecture of a mansion from the late Colonial period. Bus (computing) In computer architecture , a bus (historically also called data highway or databus )

8649-406: Was the impetus for the construction of Preble Hall. The museum has approximately 100,000 visitors each year. The Hammond-Harwood House , located at 19 Maryland Avenue, was built in 1774 for Matthias Hammond, a wealthy Maryland farmer. Its design was adapted by William Buckland from Andrea Palladio 's Villa Pisani to accommodate American Colonial regional preferences. Since 1940, when the house

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