HighWire HW400c/2 User Reference Guide Rev 1.0
5.5.3 Booting with Disk on Chip
A Disk-on-Chip (DoC) flash file system device is used on the HW400c/2 for data
storage. DoC is a high-density flash device manufactured by M-Systems
Incorporated, and has a data bus width of 16 bits. The 128 MB device is standard on
e HW400c/2, with the option of populating other devices for OEM configuratith ons.
e maximum input clock frequency of the device
clock.
nel, which in turn can be
blade. Limitations to the
kernel size are in direct proportion to the size of the RAM.
5.5.3.1 Loading the Disk on Chip
ooted. You may do this with the
ion 5.5.2
m M-Systems
B. fmt A script that invokes docshell to do the low-level
formatting of the disk-on-chip and to create two binary
C. wr0 A script that invokes docshell to write uImage (kernel
. wr1 Ramdisk to
binary partition 1.
E. uImage The kernel image.
The ramdisk image.
The sequence of commands to load the DoC (where # is the prompt) is as follows:
# ./fmt
# ./wr0
# ./wr1
Burst reads/writes to the DoC are not possible due to th
3 MHz) being slower than the 100 MHz device bus (3
The Disk-on-Chip may also be used for storing a Linux ker
ed for booting, making the HW400c/2 a true stand-alone us
Loading the DoC requires that the HW400c/2 is b
andard tftp image. See Sectst
Loading the DoC with necessary images requires the following files, all must be
cated in the same directory. lo
A. docshell A binary DoC configuration utility fro
partitions.
image) to binary partition 0.
D A script that invokes docshell to write u
F. uRamdisk
October 10, 2006 Copyright 2006, SBE, Inc. Page 84