kopia lustrzana https://gitlab.com/sane-project/website
131 wiersze
4.9 KiB
HTML
131 wiersze
4.9 KiB
HTML
<!-- received="Tue Dec 8 13:32:47 1998 PST" -->
|
||
<!-- sent="Tue, 8 Dec 1998 16:27:40 -0500" -->
|
||
<!-- name="Wolfgang Kaess" -->
|
||
<!-- email="100346.2055@compuserve.com" -->
|
||
<!-- subject="Internet Message Header" -->
|
||
<!-- id="" -->
|
||
<!-- inreplyto="" -->
|
||
<title>sane-devel: Internet Message Header</title>
|
||
<h1>Internet Message Header</h1>
|
||
<b>Wolfgang Kaess</b> (<a href="mailto:100346.2055@compuserve.com"><i>100346.2055@compuserve.com</i></a>)<br>
|
||
<i>Tue, 8 Dec 1998 16:27:40 -0500</i>
|
||
<p>
|
||
<ul>
|
||
<li> <b>Messages sorted by:</b> <a href="date.html#111">[ date ]</a><a href="index.html#111">[ thread ]</a><a href="subject.html#111">[ subject ]</a><a href="author.html#111">[ author ]</a>
|
||
<!-- next="start" -->
|
||
<li> <b>Next message:</b> <a href="0112.html">Wolfgang Kaess: "Internet Message Header"</a>
|
||
<li> <b>Previous message:</b> <a href="0110.html">Nick Lamb: "Bit of a rant, bug in PNM"</a>
|
||
<!-- nextthread="start" -->
|
||
<!-- reply="end" -->
|
||
</ul>
|
||
<!-- body="start" -->
|
||
Alan Knowles <<a href="mailto:alan_k@HK.Super.NET">alan_k@HK.Super.NET</a>> wrote: <br>
|
||
<p>
|
||
<i>> If someone can point me to a good starter page, on finding out how the ></i><br>
|
||
scanner / pc communicate, I could provide some info to help develop a ><br>
|
||
driver. I gave up sending polite notes to hp about the lack of info:) <br>
|
||
<p>
|
||
<i> > </i><br>
|
||
Hello Alan, I got the following from <br>
|
||
"Scanner Control Language (SCL) and C Language Library for <br>
|
||
Hewlett-Packard Scanners v 8.0" pdf file. <br>
|
||
<p>
|
||
Wolfgang Kaess <br>
|
||
Using SANE 0.73 with hp/xhp backend, compiled with IBM VisualAge C++ for OS/2. <br>
|
||
--------------------------------------------------------------------------- <br>
|
||
Parallel Interface Protocol <br>
|
||
Applies ScanJet ScanJet + ScanJet IIp X ScanJet 3p <br>
|
||
to: ScanJet IIc ScanJet IIcx ScanJet 6100C/4c/3c <br>
|
||
ScanJet 4p ScanJet 5p X ScanJet 5100C <br>
|
||
<p>
|
||
The HP ScanJet 5100C users an EPST driver/chip to interface a host PC to SCSI <br>
|
||
Bus device via the host s parallel port. <br>
|
||
This driver/chip converts all the control and logic functions necessary to <br>
|
||
<p>
|
||
implement the parallel-to-SCSI interface and <br>
|
||
<p>
|
||
vise versa. The EPST device conforms to the IEEE Std 1284-1994 Standard <br>
|
||
<p>
|
||
Signaling Method for a Bi-Directional <br>
|
||
<p>
|
||
Parallel Peripheral Interface for Personal Computers , and also works with <br>
|
||
<p>
|
||
non-compliant 1284 devices that allow port <br>
|
||
<p>
|
||
sharing. <br>
|
||
The parallel interface is a SCSI interface with a parallel wrapper. SCL <br>
|
||
<p>
|
||
commands are passed through the same SCSI <br>
|
||
<p>
|
||
interface as other scanners but then the signals are passed on to a parallel <br>
|
||
<p>
|
||
converter that then sends the commands to <br>
|
||
<p>
|
||
the parallel port arbitrator. The arbitrator controls the parallel bus. If <br>
|
||
<p>
|
||
the parallel bus is busy, other commands have to <br>
|
||
<p>
|
||
wait until the bus is free before they are sent on to the hardware and out to <br>
|
||
<p>
|
||
the scanner. If a printer is daisy chained to <br>
|
||
<p>
|
||
the scanner, data is passed through to the printer until a scanner specific <br>
|
||
<p>
|
||
code is received and then the scanner will <br>
|
||
<p>
|
||
block further data from passing through to the printer until the scanner <br>
|
||
<p>
|
||
command has completed. Data passed for the <br>
|
||
<p>
|
||
scanner is decoded by the parallel EPST chip on board the scanner and <br>
|
||
<p>
|
||
converted back to SCSI. Thus no additional <br>
|
||
<p>
|
||
commands are needed for parallel operations. <br>
|
||
The HP ScanJet Button Manager is still functional over the parallel interface <br>
|
||
<p>
|
||
and is handled by the EPST driver located <br>
|
||
<p>
|
||
on the host PC. If the parallel bus is busy and the Button Manager polls the <br>
|
||
<p>
|
||
scanner to see if the button has been <br>
|
||
<p>
|
||
pressed, the EPST driver reports that the button hasn t been pressed. Once <br>
|
||
<p>
|
||
the button is pressed on the scanner its state <br>
|
||
<p>
|
||
is stored in the scanner until it is read. When the parallel busy is free, <br>
|
||
<p>
|
||
the Button Manager is then allowed to read the <br>
|
||
<p>
|
||
scanner to see if the button has been pressed. <br>
|
||
If you are employing SCSI timeouts within your application, your timeouts <br>
|
||
<p>
|
||
might need to be extended 5% or more to <br>
|
||
<p>
|
||
handle the extra time associated with converting to and from parallel. In <br>
|
||
<p>
|
||
most test cases, little or no delay was <br>
|
||
<p>
|
||
observed. Test your application to see what, if any, delay is incurred. <br>
|
||
<p>
|
||
<p>
|
||
*** <br>
|
||
<p>
|
||
<p>
|
||
<p>
|
||
<pre>
|
||
--
|
||
Source code, list archive, and docs: <a href="http://www.mostang.com/sane/">http://www.mostang.com/sane/</a>
|
||
To unsubscribe: echo unsubscribe sane-devel | mail <a href="mailto:majordomo@mostang.com">majordomo@mostang.com</a>
|
||
</pre>
|
||
<!-- body="end" -->
|
||
<p>
|
||
<ul>
|
||
<!-- next="start" -->
|
||
<li> <b>Next message:</b> <a href="0112.html">Wolfgang Kaess: "Internet Message Header"</a>
|
||
<li> <b>Previous message:</b> <a href="0110.html">Nick Lamb: "Bit of a rant, bug in PNM"</a>
|
||
<!-- nextthread="start" -->
|
||
<!-- reply="end" -->
|
||
</ul>
|