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Based on kernel version 3.9. Page generated on 2013-05-02 23:11 EST.

1	This is the ALPHA version of the ltpc driver.
2	
3	In order to use it, you will need at least version 1.3.3 of the
4	netatalk package, and the Apple or Farallon LocalTalk PC card.
5	There are a number of different LocalTalk cards for the PC; this
6	driver applies only to the one with the 65c02 processor chip on it.
7	
8	To include it in the kernel, select the CONFIG_LTPC switch in the
9	configuration dialog.  You can also compile it as a module.
10	
11	While the driver will attempt to autoprobe the I/O port address, IRQ
12	line, and DMA channel of the card, this does not always work.  For
13	this reason, you should be prepared to supply these parameters
14	yourself.  (see "Card Configuration" below for how to determine or
15	change the settings on your card)
16	
17	When the driver is compiled into the kernel, you can add a line such
18	as the following to your /etc/lilo.conf:
19	
20	 append="ltpc=0x240,9,1"
21	
22	where the parameters (in order) are the port address, IRQ, and DMA
23	channel.  The second and third values can be omitted, in which case
24	the driver will try to determine them itself.
25	
26	If you load the driver as a module, you can pass the parameters "io=",
27	"irq=", and "dma=" on the command line with insmod or modprobe, or add
28	them as options in a configuration file in /etc/modprobe.d/ directory:
29	
30	 alias lt0 ltpc # autoload the module when the interface is configured
31	 options ltpc io=0x240 irq=9 dma=1
32	
33	Before starting up the netatalk demons (perhaps in rc.local), you
34	need to add a line such as:
35	
36	 /sbin/ifconfig lt0 127.0.0.42
37	
38	The address is unimportant - however, the card needs to be configured
39	with ifconfig so that Netatalk can find it.
40	
41	The appropriate netatalk configuration depends on whether you are
42	attached to a network that includes AppleTalk routers or not.  If,
43	like me, you are simply connecting to your home Macintoshes and
44	printers, you need to set up netatalk to "seed".  The way I do this
45	is to have the lines
46	
47	 dummy -seed -phase 2 -net 2000 -addr 2000.26 -zone "1033"
48	 lt0 -seed -phase 1 -net 1033 -addr 1033.27 -zone "1033"
49	
50	in my atalkd.conf.  What is going on here is that I need to fool
51	netatalk into thinking that there are two AppleTalk interfaces
52	present; otherwise, it refuses to seed.  This is a hack, and a more
53	permanent solution would be to alter the netatalk code.  Also, make
54	sure you have the correct name for the dummy interface - If it's
55	compiled as a module, you will need to refer to it as "dummy0" or some
56	such.
57	
58	If you are attached to an extended AppleTalk network, with routers on
59	it, then you don't need to fool around with this -- the appropriate
60	line in atalkd.conf is
61	
62	 lt0 -phase 1
63	
64	--------------------------------------
65	
66	Card Configuration:
67	
68	The interrupts and so forth are configured via the dipswitch on the
69	board.  Set the switches so as not to conflict with other hardware.
70	
71	       Interrupts -- set at most one.  If none are set, the driver uses
72	       polled mode.  Because the card was developed in the XT era, the
73	       original documentation refers to IRQ2.  Since you'll be running
74	       this on an AT (or later) class machine, that really means IRQ9.
75	
76	       SW1     IRQ 4
77	       SW2     IRQ 3
78	       SW3     IRQ 9 (2 in original card documentation only applies to XT)
79	
80	
81	       DMA -- choose DMA 1 or 3, and set both corresponding switches.
82	
83	       SW4     DMA 3
84	       SW5     DMA 1
85	       SW6     DMA 3
86	       SW7     DMA 1
87	
88	
89	       I/O address -- choose one.
90	
91	       SW8     220 / 240
92	
93	--------------------------------------
94	
95	IP:
96	
97	Yes, it is possible to do IP over LocalTalk.  However, you can't just
98	treat the LocalTalk device like an ordinary Ethernet device, even if
99	that's what it looks like to Netatalk.
100	
101	Instead, you follow the same procedure as for doing IP in EtherTalk.
102	See Documentation/networking/ipddp.txt for more information about the
103	kernel driver and userspace tools needed.
104	
105	--------------------------------------
106	
107	BUGS:
108	
109	IRQ autoprobing often doesn't work on a cold boot.  To get around
110	this, either compile the driver as a module, or pass the parameters
111	for the card to the kernel as described above.
112	
113	Also, as usual, autoprobing is not recommended when you use the driver
114	as a module. (though it usually works at boot time, at least)
115	
116	Polled mode is *really* slow sometimes, but this seems to depend on
117	the configuration of the network.
118	
119	It may theoretically be possible to use two LTPC cards in the same
120	machine, but this is unsupported, so if you really want to do this,
121	you'll probably have to hack the initialization code a bit.
122	
123	______________________________________
124	
125	THANKS:
126		Thanks to Alan Cox for helpful discussions early on in this
127	work, and to Denis Hainsworth for doing the bleeding-edge testing.
128	
129	-- Bradford Johnson <bradford@math.umn.edu>
130	
131	-- Updated 11/09/1998 by David Huggins-Daines <dhd@debian.org>
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