Question:
what does LTP port in commputers mean?
Steed
2006-04-17 02:01:31 UTC
what does LTP port in commputers mean?
Six answers:
Hommer
2006-04-17 02:05:58 UTC
Hello, I almost sure you meant LPT, it is the printer (usually used for) Port.



QUOTE

LPT is the original, yet still common, name of the parallel port interface on IBM PC-compatible computers. It was designed to operate a text printer that used IBM's 8-bit extended ASCII character set. The name derives from the fact that "line printer" was a common generic term at the time for any type of text printer. Graphical printers, along with a host of other devices, have been designed to communicate with the system. It was a de facto industry standard for many years, and was finally standardized as IEEE 1284 in the late 1990s. Today, the parallel port interface is seeing decreasing use because of the rise of Universal Serial Bus (USB) and FireWire (IEEE 1394) devices.



Most PC-compatible systems in the 1980s and 1990s had one or two ports, with communication interfaces defined like this:



LPT1: I/O port 0x378, IRQ 7

LPT2: I/O port 0x278, IRQ 5

Some systems also had an LPT3 port, but this was less-consistently defined. In reality, computers rarely had more than one LPT port.



A wide variety of devices were eventually designed to operate on a parallel port. Most were uni-directional (one-way) devices, only meant to respond to information sent from the PC. However, some devices such as Zip drives were able to operate in bi-directional mode. Printers also eventually took up the bi-directional system, allowing various status report information to be sent.



In MS-DOS and PC-DOS, the parallel ports could be accessed directly on the command line. For example, the command "type c:\autoexec.bat > LPT1" would direct the contents of the autoexec.bat file to the printer port. A PRN device was also available as an alias for LPT1. A special "print" command also existed to achieve the same effect. Microsoft Windows still refers to the ports in this manner in many cases, though this is often fairly hidden.



An LPT port has an 8-bit parallel databus, plus 4 pins for control output (Strobe, Linefeed, Initialize, and Select In), and 5 more for control input (ACK, Busy, Select, Error, and Paper Out).



It is actually fairly unclear exactly what "LPT" stands for. Sources have variously mentioned Line Printing Terminal, Line PrinTer, and Local PorT. According to the Jargon File, a similar port naming convention was used on ITS, DEC systems, and CP/M.
?
2016-10-16 12:03:47 UTC
Ltp Port
harish_adm123
2006-04-17 03:12:17 UTC
LTP means Local Test Port used to connect the deveices like printer and usb's
opelboy
2006-04-17 02:06:47 UTC
Its LPT not LTP. It stands for Line Printing Terminal and is now a rather redundant name for a Parallel Port, commonly used for connecting a printer to the PC.
staplez
2006-04-17 02:03:57 UTC
It's the printer port. Before USB all printers were connected through the LTP port.
druid
2006-04-17 02:05:15 UTC
It's LPT!


This content was originally posted on Y! Answers, a Q&A website that shut down in 2021.
Loading...