Manufacturing Information Solutions Forum Index Manufacturing Information Solutions
Your Place for Support and Discussions
 
 FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

LPT Printer Port Info

 
Post new topic   Reply to topic    Manufacturing Information Solutions Forum Index -> Miscellaneous Hardware
View previous topic :: View next topic  
Author Message
mistux
Site Admin


Joined: 25 Jun 2004
Posts: 1042
Location: South Bend, Indiana USA

PostPosted: Thu Jan 09, 2014 11:00 am    Post subject: LPT Printer Port Info Reply with quote

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

Logical parallel port 1: I/O port 0x3BC, IRQ 7 (usually in monochrome graphics adapters)
Logical parallel port 2: I/O port 0x378, IRQ 7 (dedicated IO cards or using a controller built into the mainboard)
Logical parallel port 3: I/O port 0x278, IRQ 5 (dedicated IO cards or using a controller built into the mainboard)

If no printer port is present at 0x3BC, the second port in the row (0x378) becomes logical parallel port 1 and 0x278 becomes logical parallel port 2 for the BIOS. Sometimes, printer ports are jumpered to share an interrupt despite having their own IO addresses (i.e. only one can be used interrupt-driven at a time). In some cases, the BIOS supports a fourth printer port as well, but the base address for it differs significantly between vendors. Since the reserved entry for a fourth logical printer port in the BIOS Data Area (BDA) is shared with other uses on PS/2 machines and with S3 compatible graphics cards, it typically requires special drivers in most environments.

Source: http://en.wikipedia.org/wiki/Parallel_port
-----------------------------------------------------------


Voltage should be 5v, some newer ones are only 3 volts.
Back to top
View user's profile Send private message Send e-mail
Display posts from previous:   
Post new topic   Reply to topic    Manufacturing Information Solutions Forum Index -> Miscellaneous Hardware All times are GMT - 5 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group