Commit 32c01266 authored by Mauro Carvalho Chehab's avatar Mauro Carvalho Chehab Committed by David S. Miller
Browse files

docs: networking: convert PLIP.txt to ReST 



- add SPDX header;
- mark code blocks and literals as such;
- adjust identation, whitespaces and blank lines where needed;
- add to networking/index.rst.

Signed-off-by: default avatarMauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent c1e4535f

Documentation/networking/index.rst

+1 −0
Original line number Diff line number Diff line
@@ -92,6 +92,7 @@ Contents: 
   packet_mmap

   phonet

   pktgen

   plip



.. only::  subproject and html

Documentation/networking/PLIP.txt→Documentation/networking/plip.rst

+25 −18
Original line number Diff line number Diff line 
.. SPDX-License-Identifier: GPL-2.0



================================================

PLIP: The Parallel Line Internet Protocol Device

================================================



Donald Becker (becker@super.org)

I.D.A. Supercomputing Research Center, Bowie MD 20715
@@ -115,7 +119,7 @@ printer "null" cable to transfer data four bits at a time using 
data bit outputs connected to status bit inputs.



The second data transfer method relies on both machines having

bi-directional parallel ports, rather than output-only ``printer''

bi-directional parallel ports, rather than output-only ``printer``

ports.  This allows byte-wide transfers and avoids reconstructing

nibbles into bytes, leading to much faster transfers.
@@ -132,7 +136,7 @@ bits with standard status register implementation. 


A cable that implements this protocol is available commercially as a

"Null Printer" or "Turbo Laplink" cable.  It can be constructed with

two DB-25 male connectors symmetrically connected as follows:

two DB-25 male connectors symmetrically connected as follows::



    STROBE output	1*

    D0->ERROR	2 - 15		15 - 2
@@ -146,6 +150,7 @@ two DB-25 male connectors symmetrically connected as follows: 
    SLCTIN	17 - 17

    extra grounds are 18*,19*,20*,21*,22*,23*,24*

    GROUND	25 - 25



    * Do not connect these pins on either end



If the cable you are using has a metallic shield it should be
@@ -155,14 +160,14 @@ Parallel Transfer Mode 1 
========================



The second data transfer method relies on both machines having

bi-directional parallel ports, rather than output-only ``printer''

bi-directional parallel ports, rather than output-only ``printer``

ports.  This allows byte-wide transfers, and avoids reconstructing

nibbles into bytes.  This cable should not be used on unidirectional

``printer'' (as opposed to ``parallel'') ports or when the machine

``printer`` (as opposed to ``parallel``) ports or when the machine

isn't configured for PLIP, as it will result in output driver

conflicts and the (unlikely) possibility of damage.



The cable for this transfer mode should be constructed as follows:

The cable for this transfer mode should be constructed as follows::



    STROBE->BUSY 1 - 11

    D0->D0	2 - 2
@@ -179,6 +184,7 @@ The cable for this transfer mode should be constructed as follows: 
    GND->ERROR	18 - 15

    extra grounds are 19*,20*,21*,22*,23*,24*

    GROUND	25 - 25



    * Do not connect these pins on either end



Once again, if the cable you are using has a metallic shield it should
@@ -188,7 +194,7 @@ PLIP Mode 0 transfer protocol 
=============================



The PLIP driver is compatible with the "Crynwr" parallel port transfer

standard in Mode 0.  That standard specifies the following protocol:

standard in Mode 0.  That standard specifies the following protocol::



   send header nibble '0x8'

   count-low octet
@@ -196,7 +202,8 @@ standard in Mode 0. That standard specifies the following protocol: 
   ... data octets

   checksum octet



Each octet is sent as

Each octet is sent as::



	<wait for rx. '0x1?'>	<send 0x10+(octet&0x0F)>

	<wait for rx. '0x0?'>	<send 0x00+((octet>>4)&0x0F)>
@@ -205,7 +212,7 @@ That raises the ACK line, triggering an interrupt in the receiving 
machine.  The receiving machine disables interrupts and raises its own ACK

line.



Restated:

Restated::



  (OUT is bit 0-4, OUT.j is bit j from OUT. IN likewise)

  Send_Byte:

drivers/net/plip/Kconfig

+1 −1
Original line number Diff line number Diff line
@@ -21,7 +21,7 @@ config PLIP 
	  bits at a time (mode 0) or with special PLIP cables, to be used on

	  bidirectional parallel ports only, which can transmit 8 bits at a

	  time (mode 1); you can find the wiring of these cables in

	  <file:Documentation/networking/PLIP.txt>.  The cables can be up to

	  <file:Documentation/networking/plip.rst>.  The cables can be up to

	  15m long.  Mode 0 works also if one of the machines runs DOS/Windows

	  and has some PLIP software installed, e.g. the Crynwr PLIP packet

	  driver (<http://oak.oakland.edu/simtel.net/msdos/pktdrvr-pre.html>)

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