ISADUMP(8)                (April 2011)                 ISADUMP(8)

          isadump - examine ISA registers

          isadump [-y] [-W|-L] [-k V1,V2...]  addrreg datareg [bank
          [bankreg]] #for I2C-like access
          isadump -f [-y] [-W|-L] address [range [bank [bankreg #for
          flat address space

          isadump is a small helper program to examine registers visi-
          ble through the ISA bus. It is intended to probe any chip
          that lives on the ISA bus working with an address register
          and a data register (I2C-like access) or a flat range (of up
          to 256 bytes).

          -f   Enable flat address space mode.

          -y   Disable interactive mode. By default, isadump will wait
               for a confirmation from the user before messing with
               the ISA bus. When this flag is used, it will perform
               the operation directly. This is mainly meant to be used
               in scripts.

          -k V1,V2...
               Specify a comma-separated list of bytes to send as the
               key sequence to enter the chip configuration mode. Most
               Super-I/O chips need this.  Known key sequences are:
               0x87,0x01,0x55,0x55 for ITE, 0x55 for SMSC, 0x87,0x87
               for Winbond and VIA, none needed for National Semicon-

          -W   Perform 16-bit reads.

          -L   Perform 32-bit reads.

     OPTIONS (I2C-like access mode)
          At least two options must be provided to isadump. addrreg
          contains the ISA address of the address register for the
          chip to probe; datareg contains the address of the data reg-
          ister. Both addresses are integers between 0x0000 and
          0x3FFF. Usually, if the chip's base address is 0x0nn0, the
          address register is at 0x0nn5 and the data register is at
          0x0nn6. The most common base address for hardware monitoring
          chips is 0x0290.

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          For Super-I/O chips, address register is typically at 0x2E
          with data register at 0x2F.

          The bank and bankreg parameters are useful on the Winbond
          chips as well as on Super-I/O chips.  bank is an integer
          between 0 and 31, and bankreg is an integer between 0x00 and
          0xFF (default value: 0x4E for Winbond chips, 0x07 for
          Super-I/O chips). The W83781D datasheet has more information
          on bank selection.

     OPTIONS (flat address space mode)
          In flat mode, only one parameter is mandatory. address con-
          tains the ISA address of the chip to probe; it is an integer
          between 0x0000 and 0xFFFF.  If provided, range is how many
          bytes should be read (must be a multiple of 16). If the
          range isn't provided, it defaults to 256 bytes and the
          address is forcibly aligned on a 256-byte boundary.

          The bank and bankreg parameters are useful on the National
          Semiconductor PC87365 and PC87366 Super-I/O chips.  bank is
          an integer between 0 and 31, and bankreg is an integer
          between 0x00 and 0xFF (default value: 0x09; must fit in the
          specified range). See the PC87365 datasheet for more infor-
          mation on bank selection.

          If no bank is specified, no bank change operation is per-

          If a bank is specified, the original value is restored
          before isadump exits.

          Dumping Super-I/O chips is typically a two-step process.
          First, you will have to access the main Super-I/O address
          using a command like: isadump 0x2e 0x2f 0x09.  This will
          select logical device 9 (correct value depend on the chip).
          At 0x60 you will find the logical device address word, for
          example "ec c0".  Then you can use a command like: isadump
          -f 0xecc0 16.  This will dump the logical device registers.
          The correct range depends on the chip.

          Poking around in ISA data space is extremely dangerous.
          Running isadump with random parameters can cause system
          crashes, data loss, and worse!  Be extremely careful when
          using this program.


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          i2cdump(8), isaset(8)

          Frodo Looijaard, Mark D. Studebaker, and the lm_sensors
          group (

          This manual page was originally written by David Z Maze
          <> for the Debian GNU/Linux system. It was
          then reviewed and augmented by the lm_sensors team and is
          now part of the lm_sensors source distribution.

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