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ckshivaram
Joined: 21 Apr 2008
Posts: 331
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Location: india
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 07 May 2008 6:40 buffer and port |
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| anyone can tell the basic difference between port and buffer. What is the functionality difference.
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ermtariq
Joined: 01 Apr 2008
Posts: 10
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07 May 2008 6:58 Re: buffer and port |
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PORT
On computer and telecommunication devices, a port (noun) is generally a specific place for being physically connected to some other device, usually with a socket and plug of some kind. Typically, a personal computer is provided with one or more serial ports and usually one parallel port. The serial port supports sequential, one bit-at-a-time transmission to peripheral devices such as scanners and the parallel port supports multiple-bit-at-a-time transmission to devices such as printers.
2) In programming, a port (noun) is a "logical connection place" and specifically, using the Internet's protocol, TCP/IP, the way a client program specifies a particular server program on a computer in a network. Higher-level applications that use TCP/IP such as the Web protocol, Hypertext Transfer Protocol, have ports with preassigned numbers. These are known as "well-known ports" that have been assigned by the Internet Assigned Numbers Authority (IANA). Other application processes are given port numbers dynamically for each connection. When a service (server program) initially is started, it is said to bind to its designated port number. As any client program wants to use that server, it also must request to bind to the designated port number.
Port numbers are from 0 to 65536. Ports 0 to 1024 are reserved for use by certain privileged services. For the HTTP service, port 80 is defined as a default and it does not have to be specified in the Uniform Resource Locator (URL).
3) In programming, to port (verb) is to move an application program from an operating system environment in which it was developed to another operating system environment so it can be run there. Porting implies some work, but not nearly as much as redeveloping the program in the new environment. open standard programming interface (such as those specified in X/Open's 1170 C language specification and Sun Microsystem's Java programming language) minimize or eliminate the work required to port a program.
BUFFER:-
A temporary storage area, usually in RAM. The purpose of most buffers is to act as a holding area, enabling the CPU to manipulate data before transferring it to a device.
Because the processes of reading and writing data to a disk are relatively slow, many programs keep track of data changes in a buffer and then copy the buffer to a disk. For example, word processors employ a buffer to keep track of changes to files. Then when you save the file, the word processor updates the disk file with the contents of the buffer. This is much more efficient than accessing the file on the disk each time you make a change to the file.
Note that because your changes are initially stored in a buffer, not on the disk, all of them will be lost if the computer fails during an editing session. For this reason, it is a good idea to save your file periodically. Most word processors automatically save files at regular intervals.
Buffers are commonly used when burning data onto a compact disc, where the data is transferred to the buffer before being written to the disc.
Another common use of buffers is for printing documents. When you enter a PRINT command, the operating system copies your document to a print buffer (a free area in memory or on a disk) from which the printer can draw characters at its own pace. This frees the computer to perform other tasks while the printer is running in the background. Print buffering is called spooling.
Most keyboard drivers also contain a buffer so that you can edit typing mistakes before sending your command to a program. Many operating systems, including DOS, also use a disk buffer to temporarily hold data that they have read from a disk. The disk buffer is really a cache.
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ckshivaram
Joined: 21 Apr 2008
Posts: 331
Helped: 23
Location: india
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07 May 2008 7:10 buffer and port |
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microcontroller has both port and buffer, what is the difference between them. with respect to data storage.
Why cant i send data or receive directly from buffer, why a prt interface is needed
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ermtariq
Joined: 01 Apr 2008
Posts: 10
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07 May 2008 7:24 Re: buffer and port |
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PORT
On computer and telecommunication devices, a port (noun) is generally a specific place for being physically connected to some other device, usually with a socket and plug of some kind. Typically, a personal computer is provided with one or more serial ports and usually one parallel port. The serial port supports sequential, one bit-at-a-time transmission to peripheral devices such as scanners and the parallel port supports multiple-bit-at-a-time transmission to devices such as printers.
2) In programming, a port (noun) is a "logical connection place" and specifically, using the Internet's protocol, TCP/IP, the way a client program specifies a particular server program on a computer in a network. Higher-level applications that use TCP/IP such as the Web protocol, Hypertext Transfer Protocol, have ports with preassigned numbers. These are known as "well-known ports" that have been assigned by the Internet Assigned Numbers Authority (IANA). Other application processes are given port numbers dynamically for each connection. When a service (server program) initially is started, it is said to bind to its designated port number. As any client program wants to use that server, it also must request to bind to the designated port number.
Port numbers are from 0 to 65536. Ports 0 to 1024 are reserved for use by certain privileged services. For the HTTP service, port 80 is defined as a default and it does not have to be specified in the Uniform Resource Locator (URL).
3) In programming, to port (verb) is to move an application program from an operating system environment in which it was developed to another operating system environment so it can be run there. Porting implies some work, but not nearly as much as redeveloping the program in the new environment. open standard programming interface (such as those specified in X/Open's 1170 C language specification and Sun Microsystem's Java programming language) minimize or eliminate the work required to port a program.
BUFFER:-
A temporary storage area, usually in RAM. The purpose of most buffers is to act as a holding area, enabling the CPU to manipulate data before transferring it to a device.
Because the processes of reading and writing data to a disk are relatively slow, many programs keep track of data changes in a buffer and then copy the buffer to a disk. For example, word processors employ a buffer to keep track of changes to files. Then when you save the file, the word processor updates the disk file with the contents of the buffer. This is much more efficient than accessing the file on the disk each time you make a change to the file.
Note that because your changes are initially stored in a buffer, not on the disk, all of them will be lost if the computer fails during an editing session. For this reason, it is a good idea to save your file periodically. Most word processors automatically save files at regular intervals.
Buffers are commonly used when burning data onto a compact disc, where the data is transferred to the buffer before being written to the disc.
Another common use of buffers is for printing documents. When you enter a PRINT command, the operating system copies your document to a print buffer (a free area in memory or on a disk) from which the printer can draw characters at its own pace. This frees the computer to perform other tasks while the printer is running in the background. Print buffering is called spooling.
Most keyboard drivers also contain a buffer so that you can edit typing mistakes before sending your command to a program. Many operating systems, including DOS, also use a disk buffer to temporarily hold data that they have read from a disk. The disk buffer is really a cache.
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davidgrm
Joined: 08 Apr 2006
Posts: 232
Helped: 21
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07 May 2008 15:56 Re: buffer and port |
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| microcontroller has both port and buffer, what is the difference between them. with respect to data storage. |
On a microcontroller the term port usually refers to a group of input/output pins. A buffer is a memory register of some sort. Most io ports incorporate buffers that keep a copy of data that has been output via the port. Most also allow you to input data directly from the port pin, this gives actual values being input into the device or you can read the data from the port buffer, this will show you what was out earlier
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