root/i2c-tools/trunk/tools/i2cdump.8 @ 5140

Revision 5140, 3.0 KB (checked in by khali, 6 years ago)

Remove reference to hardware monitoring chips. i2cdump works on all I2C/SMBus
chips, not just hardware monitoring chips.

  • Property svn:eol-style set to native
  • Property svn:keywords set to Author Date Id Revision
Line 
1.TH I2CDUMP 8 "March 2008"
2.SH NAME
3i2cdump \- examine I2C registers
4
5.SH SYNOPSIS
6.B i2cdump
7.RB [ -f ]
8.RB [ -y ]
9.I i2cbus
10.I address
11.RI [ mode ]
12.RI [ "bank " [ bankreg ]]
13.br
14.B i2cdump
15.B -V
16
17.SH DESCRIPTION
18i2cdump is a small helper program to examine registers
19visible through the I2C bus.
20
21.SH OPTIONS
22.TP
23.B -V
24Display the version and exit.
25.TP
26.B -f
27Force access to the device even if it is already busy. By default, i2cdump
28will refuse to access a device which is already under the control of a
29kernel driver. Using this flag is dangerous, it can seriously confuse the
30kernel driver in question. It can also cause i2cdump to return invalid
31results. So use at your own risk and only if you know what you're doing.
32.TP
33.B -y
34Disable interactive mode. By default, i2cdump will wait for a confirmation
35from the user before messing with the I2C bus. When this flag is used, it
36will perform the operation directly. This is mainly meant to be used in
37scripts.
38.PP
39At least two options must be provided to i2cdump. \fIi2cbus\fR indicates the
40number of the I2C bus to be scanned. This number should correspond to one
41of the busses listed by \fIi2cdetect -l\fR. \fIaddress\fR indicates the
42address to be scanned on that bus, and is an integer between 0x00 and 0x7F.
43.PP
44The \fImode\fR parameter, if specified, is one of the letters \fBb\fP, \fBw\fP,
45\fBs\fP, or \fBi\fP, corresponding to a read size of a single byte, a 16-bit
46word, an SMBus block, an I2C block, respectively. The \fBc\fP mode is a
47little different, it reads all bytes consecutively, and is useful for chips that
48have an address auto-increment feature, such as EEPROMs. The \fBW\fP mode is
49also special, it is similar to \fBw\fP except that a read command will only
50be issued on even register addresses; this is again mainly useful for EEPROMs.
51.PP
52A \fBp\fP can also be appended to the \fImode\fR parameter (except for
53\fBi\fP and \fBW\fP) to enable PEC. If the \fImode\fR parameter is omitted,
54i2cdump defaults to byte access without PEC.
55.PP
56The \fIbank\fR and \fIbankreg\fR parameters are useful on the W83781D and
57similar chips (at the time of writing, all Winbond and Asus chips).
58\fIbank\fR is an integer between 0 and 7, and \fIbankreg\fR is an integer
59between 0x00 and 0xFF (default value: 0x4E). The W83781D data sheet has more
60information on bank selection.
61
62.SH WARNING
63i2cdump can be dangerous if used improperly. Most notably, the \fBc\fP mode
64starts with WRITING a byte to the chip. On most chips it will be stored in the
65address pointer register, which is OK, but some chips with a single register
66or no (visible) register at all will most likely see this as a real WRITE,
67resulting in possible misbehavior or corruption. Do not use i2cdump
68on random addresses. Anyway, it is of little use unless you have good
69knowledge of the chip you're working with and an idea of what you are looking
70for.
71
72.SH SEE ALSO
73i2cset(8), i2cdetect(8), isadump(8)
74
75.SH AUTHOR
76Frodo Looijaard, Mark D. Studebaker and Jean Delvare
77
78This manual page was originally written by David Z Maze <dmaze@debian.org> for
79the Debian GNU/Linux system.
Note: See TracBrowser for help on using the browser.