Parallel Port Maximum Speed!?

[VB IT]

What is the maximum speed of parallel port i.e. what will be the maximum frequency of transferring signals in and out for different Parallel Prot modes.

[VB IT]

No One!

[phinds]

there are many kinds of parallel port cards. Do an internet search and you'll find all kinds of information

[Pirate]

Slow , if I remember correctly it's about 4 mbps .

[wrack]

Does this be of any help...???

Parallel Port Speed
To obtain the optimum transmission rate from your paral-lel port, the port should be set to the fastest speed possi-ble. Your PC may have been shipped with the parallel port set by default to unidirectional mode (the data rate used for communication with your printer), even if it is capable of faster operation. To confirm what speed your parallel port is set to, consult your computer owner’s manual, or check with your dealer or PC manufacturer.
If your parallel port is currently operating in unidirec-tional mode, you will achieve faster transmission from:
• bi-directional mode—approximately twice the rate pro-vided by unidirectional mode
• ECP (enhanced capabilities port) mode—approximately four times the rate provided by unidirectional mode
Changing the speed of your parallel port requires either entering the CMOS (firmware) set-up utility of your com-puter’s BIOS (basic input-output system) or relocating hardware jumpers on your computer’s motherboard.
Care must be taken in changing these settings. If you make a mistake, it is possible to disable your com-puter’s basic operation. Consult your computer’s docu-mentation before proceeding. If you are not comfortable making the changes, consult your computer retailer or manufacturer, or a local computer service center, for as-sistance.

[wrack]

Found something else too..

A brief history of parallel ports
When computers started to conquer small offices and homes in the early 1980's, they were equipped with a port that would let you connect to either a printer or plotter. This "Centronics" port is what we now call a unidirectional parallel port or a Standard Parallel Port (SPP).

It didn't take long for people to see that a parallel port could transfer data faster than a serial port: theoretically 5 times faster.

But there was a bottle-neck caused by the design of the port. The SPP provided only 4 wires with which to transfer data. Parallel port file transfer was faster than serial transfer but the extra speed didn't justify the extra cost.

Later, when IBM introduced the PS/2 line of computers, they also introduced a new standard called "bi-directional". The new port had 8 data lines with which to transfer data and transfer speed increased to 150 Kbytes/sec and more.

Many companies redesigned their products to take advantage of the parallel port's speed. Such devices as hard disks, scanners, CD-ROM drives, CCD cameras and even networks appeared in rapid succession.

Three companies (Intel, Zenith and Xircom) created a new standard called EPP (Enhanced Parallel Port), which increased the transfer speed of the port to 1000 Kbytes/sec.

Finally, Microsoft introduced another standard called ECP (Enhanced Capability Port) and the transfer rate jumped to 2000 Kbytes/sec. Unfortunately all these different protocols are only partially compatible with each other. It's a matter of "plug and pray", i.e., try it and hope that it works for you and your hardware.

[VB IT]

Originally posted by wrack
Found something else too..
Finally, Microsoft introduced another standard called ECP (Enhanced Capability Port) and the transfer rate jumped to 2000 Kbytes/sec. Unfortunately all these different protocols are only partially compatible with each other. It's a matter of "plug and pray", i.e., try it and hope that it works for you and your hardware.

So I Can Transfer 2000 Kb/Sec by Parallel Port in ECP Mode. So if I make circuit that transfer 2000 Kbytes/Sec my Data will not lost.

Thanks Again

[wrack]

Originally posted by VB IT
So I Can Transfer 2000 Kb/Sec by Parallel Port in ECP Mode. So if I make circuit that transfer 2000 Kbytes/Sec my Data will not lost.
Thanks Again

In theory it shouldn't but practically I have no idea. But if I were u then I will put 20% overhead and then start working on it. I would go for 1500 KBytes/Sec.

Cheers.

[Admiral Michael]

do you know how to use the parallel port in vb? If not goto: Click Here

Click Projects>Parallel Port in VB

THe only thing is that a program must be installed first. Believe me this is the only free way I have found, I found a few that you have to pay for to access the parallelport.

[wrack]

Good site but I have never got a chance to use that port in my life so far. And I believe that you can do that by VC++ or some nifty sub classing.

Cheers.