Solved

LPT port

Posted on 1998-12-29
3
818 Views
Last Modified: 2012-08-14
It may not be the right place to ask this question, BUT here it is :

I'm in NEED of informations about how does the LPT work, send and recive data

any suggestions or addresses I have to go for ?

Thanks  
anas
0
Comment
Question by:anas_madani
3 Comments
 
LVL 1

Expert Comment

by:hddp666
ID: 1132074
Try yahoo, hotbot and other search engines using LPT, parallel port, pinout, etc. There are a lot of articles and papers on ports, including how to write programs to control them.
0
 

Accepted Solution

by:
tracyc earned 20 total points
ID: 1132075
I hope your in a reading mood......

The LPT port (parallel port or centronics port), sends many bits of data along eight wires at a time as apposed to the serial port
which sends only one bit of data at a time along one wire.

Comming out of the computer through the 25-Pin parallel connection it works like this:

a) A signal on line 13 (the select line) from the printer or whatever tells the computer it is online and ready

b) Data is sent (at around five volts for a 1 and nearly 0 volts for a 0) on lines 2 through 9.

c) Then line one sends a strobe signal to the device to let that device know it should read the data that was just sent.  (This happens very fast!)

d) Line 11 tells the PC if the device is currently to busy to read the data.

e) Line 10 tells the PC that the device has read the data from lines 2 through 9 and is ready for more.

f) Line 12 tells the PC if the printer is out of paper.

g) Line 15 tells the PC that some error condition exests, but doesn't say what.

h) Line 16 is user to cause the printer to reset itself.

i) Line 14 tells the printer to do advance the paper one line for a carriage return when low-voltage is present or just advance one line for line advance code when high voltage is present.

j) Line 17 is only used on some printers that can use it to receive a code from the PC to turn on or off.

Thats pretty much it.    
0
 
LVL 1

Expert Comment

by:MatthewL
ID: 1132076
0

Featured Post

Superior storage. Superior surveillance.

WD Purple drives are built for 24/7, always-on, high-definition security systems. With support for up to 8 hard drives and 32 cameras, WD Purple drives are optimized for surveillance.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

We recently endured a series of broadcast storms that caused our ISP to shut us down for brief periods of time. After going through a multitude of tests, we determined that the issue was related to Intel NIC drivers on some new HP desktop computers …
The Rasberry PI is a low cost piece of hardware that you can have a lot of fun with through experimenting and building/working on projects like media players, running a low cost computer, build data loggers etc. - see: https://www.raspberrypi.org
This Micro Tutorial hows how you can integrate  Mac OSX to a Windows Active Directory Domain. Apple has made it easy to allow users to bind their macs to a windows domain with relative ease. The following video show how to bind OSX Mavericks to …
Migrating to Microsoft Office 365 is becoming increasingly popular for organizations both large and small. If you have made the leap to Microsoft’s cloud platform, you know that you will need to create a corporate email signature for your Office 365…

867 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

15 Experts available now in Live!

Get 1:1 Help Now