Kernel driver scx200_acb

Author: Christer Weinigel <>

The driver supersedes the older, never merged driver named i2c-nscacb.

Module Parameters

  • base: up to 4 ints Base addresses for the ACCESS.bus controllers on SCx200 and SC1100 devices

    By default the driver uses two base addresses 0x820 and 0x840. If you want only one base address, specify the second as 0 so as to override this default.


Enable the use of the ACCESS.bus controller on the Geode SCx200 and SC1100 processors and the CS5535 and CS5536 Geode companion devices.

Device-specific notes

The SC1100 WRAP boards are known to use base addresses 0x810 and 0x820. If the scx200_acb driver is built into the kernel, add the following parameter to your boot command line:


If the scx200_acb driver is built as a module, add the following line to a configuration file in /etc/modprobe.d/ instead:

options scx200_acb base=0x810,0x820