other DHT-Walnut pages: DHT-Walnut-flameman
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 Media:amd29lv040b.pdf 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 [wiki:DHT-Walnut-Known-Working-Hardware 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 [[[Media:hardbreak.tgz]] hardbreak.tgz]
- OCD Commander macro file to dump the CPU configuration (all but PCI) Media:dump_config.mac dump_config.mac
- OCD Commander macro file to configure the system for recovery Media:recovery_config.mac recovery_config.mac
- CPU configuration of the system after a warm reset Media:warm_reset.config warm_reset.config
- CPU configuration of the system once ppcboot v1.1.2 is up and running Media:ppcboot.config ppcboot.config
- CPU configuration of the system once ppcboot v1.1.6 is up and running Media:ppcboot_116.config ppcboot_116.config]
- Example OCD logfile of the using the recovery macro to load ppcboot Media:ocd_recovery_log.txt ocd_recovery_log.txt
- Example console log from ppcboot v.1.1.6 running from ram after recovery macro Media:ocd_recovery_console_log.txt ocd_recovery_console_log.txt
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: 
Here is a binary for those without a toolchain.
[[[Media:ppcboot126.96.36.199.bin]] ppcboot188.8.131.52.bin] crc = 083fb0a3
To use this (at your own risk) see the detailed update procedure description: [wiki:DHT-WalnutInstallingTheUpdatedBootloader Installing the Updated Bootloader]
U-Boot is a significantly updated replacement for ppcboot. See: [wiki:DHT-Walnut-U-Boot U-Boot for the DHT-Walnut].
Just in case you make a brick, there is hope: [wiki:DHT-WalnutJtagBootloaderInstallation JTAG Bootloader Installation]
- Version 2.4
(Mostly) working kernel binary and config from jbevren with matrox fbcon and usb input support.
- Version 2.6
See: [wiki:DHT-Walnut2.6LinuxKernel 2.6 Linux kernel for the DHT-Walnut].
- [wiki:DHT-Walnut-DebianInstall Debian GNU/Linux netboot installer] -- Install Debian from the internet to a hard disk.
- How To [wiki:DHT-WalnutInstallingTheUpdatedBootloader replace the bootloader with ppcboot 1.1.6]
- How To [wiki:DHT-Walnut-U-Boot replace the bootloader with U-boot 1.1.4]
- How To [wiki:DHT-WalnutJtagBootloaderInstallation recover from "Brickage"]
- How To [wiki:DHT-WalnutAddJ10 add the JTAG connector at J10]
- How To [wiki:DHT-WalnutBootViaTftp boot via tftp]
- How To [wiki:DHT-WalnutBootingFromHdd boot from Hard Disk]
- How To [wiki:DHT-WalnutUsefullProjects do something useful with your board]
- How To [wiki:DHT-WalnutGPIO control the Green Media LED and J5]
- More to come...