DHT-Walnut

other DHT-Walnut pages:  Flameman/dht-walnut

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 [[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 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]]

Bootloaders

 * ppcboot

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.

[[Media:Patch-ppcboot-1.1.6-km2|patch-ppcboot-1.1.6-km2]]

Original sources for ppcboot:

Here is a binary for those without a toolchain.

[[Media:Ppcboot1.1.6.1.bin|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]]


 * 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...