From: eLinux.org
DHT-Walnut
other DHT-Walnut pages:
Flameman/dht-walnut
Contents
Overview
DHT-Walnut is a shortened name for the Digital Home Technologies PCB
01070201 Rev. 1.1. The DHT-Walnut board is based on the AMCC-Walnut
(still available, and still expensive :P). It is a more improved board
described at www.amcc.com. A “walnut” searching will inform about
schematic and software. Also keep attention @ DENX: they have developed
a lot for the AMCC-Walnut board, and you could find a linux patch for
your problem, prettier documentation, developer suit, and much more: in
case, you are suggested to have a look to their web pages.
currently available
HERE Oops, sold
out 2/6/2006
The board consists of:
- PowerPC 405GP running at 266mhz
- PC133 SDRAM slot, currently, only supports single sidded DIMMs
- On-chip 405GP ethernet, board doesn’t have an ethernet MAC address
- DCE serial port, speeds up to 230k, only tested to 115200
- two pci slots, keyed for 5V only cards
- Promise Technologies PDC20265 IDE
- 512k of boot flash AMD 29LV040B
datasheet - 12v dc powered
- PPC40XX JTAG on J10
- 6.00” x 7.5” board size
The system’s most common configuration seems to be:
- System PCB
- 32M PC133 SDRAM DIMM
- Unknown PCI IEEE-1394 card supported by OHCI driver
- PPCBoot v.1.1.2 in flash
Hardware that is known to work (and not to work) with this board can be
found
here
GPSFan (Freenode IRC on #edev) was helpful in providing an image of the
board:
Some info in the pdf HERE
Experimental hack to set a hardware breakpoint inside OCD Commander
hardbreak.tgz
- OCD Commander macro file to dump the CPU configuration (all but PCI)
dump_config.mac - OCD Commander macro file to configure the system for recovery
recovery_config.mac - CPU configuration of the system after a warm reset
warm_reset.config - CPU configuration of the system once ppcboot v1.1.2 is up and
running
ppcboot.config - CPU configuration of the system once ppcboot v1.1.6 is up and
running
ppcboot_116.config - Example OCD logfile of the using the recovery macro to load ppcboot
ocd_recovery_log.txt - Example console log from ppcboot v.1.1.6 running from ram after
recovery macro
ocd_recovery_console_log.txt
Bootloaders
Here is the latest ppcboot 1.1.6 patch, as is, it will build for
flashing at 0xfff80000 as a replacement for the pcboot-1.1.2 that comes
with the board.
Original sources for ppcboot:
[1]
Here is a binary for those without a toolchain.
ppcboot1.1.6.1.bin
crc = 083fb0a3
To use this (at your own risk) see the detailed update procedure
description: Installing the Updated
Bootloader
- U-Boot
U-Boot is a significantly updated replacement for ppcboot. See: U-Boot
for the DHT-Walnut.
Just in case you make a brick, there is hope: JTAG Bootloader
Installation
Linux Kernels
- Version 2.4
(Mostly) working kernel binary and config from jbevren with matrox fbcon
and usb input support.
Current issues:
- USB keyboard input doesnt seem to work, but events reach
/dev/input/event0 - Media:uImage
- Media:config
- USB keyboard input doesnt seem to work, but events reach
Version 2.6
See: 2.6 Linux kernel for the
DHT-Walnut
Userland
- Debian GNU/Linux netboot
installer
— Install Debian from the internet to a hard disk.
How-To’s
- How To replace the bootloader with ppcboot
1.1.6 - How To replace the bootloader with U-boot
1.1.4 - How To recover from
“Brickage” - How To add the JTAG connector at
J10 - How To boot via
tftp - How To boot from Hard
Disk - How To do something useful with your
board - How To control the Green Media LED and
J5 - More to come…