moved to Parallel Port Signal Detail
DB-25 Pin |
Driven by | Signal Name | Cent Pin |
||
1 | Host | /Strobe | 1 | Tells the printer that data is available on Data 0-7. Pulse width must be more than 0.5us. Must be high if Busy or /Acknowledge are also high. driven by 7405 inverting open collector buffers, pulled to +5 volts via 4.7K resistors. | |
2 | Host | Data 0 | 2 | Data lines must be valid 0.5us before falling edge of Strobe
signal.
The Data Out pins were orginally driven by a 74LS374 octal latch, which could source 2.6 mA and sink 24 mA. It is essential that the external device not try to pull these lines to ground, as this might cause the 74LS374 to source more current than it could handle without damage. Exception: bidirectional printer ports allow the 74LS374 (or equivalent) driver chip to be tri-stated. |
|
3 | Host | Data 1 | 3 | ||
4 | Host | Data 2 | 4 | ||
5 | Host | Data 3 | 5 | ||
6 | Host | Data 4 | 6 | ||
7 | Host | Data 5 | 7 | ||
8 | Host | Data 6 | 8 | ||
9 | Host | Data 7 | 9 | ||
10 | Printer | /Ack | 10 | Pulse width approx 3us. Asserted when Busy goes off or after data is accepted. Also pulsed when printer comes on line after power on, reset, or operater selects online mode. Inverted in Status Input register | |
11 | Printer | Busy | 11 | Indicates that the printer is busy. Asserted during reading of data, printing, errors, and when offline. | |
12 | Printer | Out of Paper | 12 | ||
13 | Printer | Select | 13 | High when printer is online. | |
14 | Host | /Auto Feed | 14 | driven by 7405 inverting open collector buffers, pulled to +5 volts via 4.7K resistors. | |
15 | Printer | /Error | 32 | ||
16 | Host | /Initialize | 31 | driven by 7405 inverting open collector buffers, pulled to +5 volts via 4.7K resistors. Double inverted from the control register. | |
17 | Host | /Select Input | 36 | driven by 7405 inverting open collector buffers, pulled to +5 volts via 4.7K resistors. | |
18-35 | Both | Ground | 30 | ||
Ground returns | 19-29 |
see also:
file: /Techref/io/parallel.htm, 7KB, , updated: 2009/9/17 12:05, local time: 2024/11/8 15:11,
18.119.159.148:LOG IN ©2024 PLEASE DON'T RIP! THIS SITE CLOSES OCT 28, 2024 SO LONG AND THANKS FOR ALL THE FISH!
|
©2024 These pages are served without commercial sponsorship. (No popup ads, etc...).Bandwidth abuse increases hosting cost forcing sponsorship or shutdown. This server aggressively defends against automated copying for any reason including offline viewing, duplication, etc... Please respect this requirement and DO NOT RIP THIS SITE. Questions? <A HREF="http://sxlist.com/Techref/io/parallel.htm"> Centronix Parallel Ports</A> |
Did you find what you needed? |
Welcome to sxlist.com!sales, advertizing, & kind contributors just like you! Please don't rip/copy (here's why Copies of the site on CD are available at minimal cost. |
Welcome to sxlist.com! |
.