README

dcload-ip 1.0.5
A Dreamcast ethernet loader originally by <andrewk@napalm-x.com>

Features

* Load elf, srec, and bin
* PC I/O (read, write, etc to PC - compatible with original dcload)
* Exception handler
* Extremely fast (at least for me - I get 1130Kbyte/sec on 10mbit half-duplex)
* Now works on 100mbit (I get 2580Kbyte/sec on 100mbit half-duplex)
* Supports both the Broadband Adapter (HIT-0400) and Lan Adapter (HIT-0300)
  in a single binary

Building

1. Edit Makefile.cfg for your system and network, and then run make

Installation

1. PC - run make install (installs dc-tool)
2. DC
   a. cd make-cd, edit Makefile, insert blank cd-r, run make
 or 
   b. take target-src/1st_read/1st_read.bin and stuff it on a cd yourself
      (please use the IP.BIN from the make-cd directory if you are going
       to distribute either cds or cd images)
  
On-screen display

* If you see the message "NO ETHERNET ADAPTER DETECTED!", something has
  gone wrong. The background of the screen will be red.

* The correct display is something like:
  dcload-ip 1.0.4               <- name/version
  Broadband Adapter (HIT-0400)  <- adapter driver in use
  00:d0:f1:02:ab:dd             <- dc hardware address
  c0.a8.00.04                   <- dc ip address (in hex)
  idle...                       <- status

  The background of the screen will be blue.

* For the Broadband Adapter only: if the status line reports "link
  change..." and does not change back to "idle..." within a short period
  of time, you may have a cable problem. dcload-ip will not work while
  "link change..." is displayed, or before it is displayed the first time.
  The "link change..." message normally is seen when you start dcload-ip,
  when you execute dc-tool -r, and when you disconnect the ethernet cable.

* If an exception is caught while a loaded program is running, the screen
  will turn lighter blue and display the exception info. dcload-ip should be
  active again after that point.

Testing

1. cd example-src
2. dc-tool -x console-test (tests some PC I/O)
3. dc-tool -x exception-test (generates an exception)
4. dc-tool -x gethostinfo (displays the Dreamcast's ip, and the ip and port of
   the dc-tool host)

KOS GDB-over-dcload

To run a GNU debugger session over the dcload connection:

1. Build/obtain an sh-elf targetted GNU debugger
2. Put a 'gdb_init()' call somewhere in the startup area of your
   KOS-based program
3. Build your program with the '-g' GCC switch to include debugging info
4. Launch your program using 'dc-tool -g -x <prog.elf>'
5. Launch sh-elf-gdb and connect to the dc-tool using 'target remote :2159'
6. Squash bugs

Maple Passthrough

You can send packets to various maple devices attached to the Dreamcast by
sending using the MAPL command. Simply send a command packet to the Dreamcast
that is formatted as follows:

command id: 'MAPL'
command address: 0 (ignored)
command size: length of maple packet, in bytes
command data:
    Maple Command (1 byte)
    Maple Port # (1 byte)
    Maple Slot # (1 byte)
    Maple data in 4-byte increments (1 byte)
    Any data to be sent with the command (multiple of 4 bytes)

You will get a similarly formatted response in return.

Notes

* You can use arp instead of setting the dreamcast's ip in Makefile.cfg
* Tested systems: Debian GNU/Linux 2.2-3.0, Cygwin
* There are almost certainly bugs
* Patches and improvements are welcome; please send to the cadcdev tracker
  on SourceForge

Credits
* rtl8139 code based on code by Dan Potter
* Lan Adapter driver is pulled from an early version of the KOS LA driver
* There are some various files from newlib-1.8.2 here
* video.s, maple.c, and maple.h were written by Marcus Comstedt
* initial win32 porting and implementation of -t by Florian 'Proff' Schulze
* win32 bugfix by The Gypsy
* fixes for cygwin by Florian 'Proff' Schulze
* rx config bug pointed out by Slant
* horridly buggy nature of 1.0.1 + 1.0.2 pointed out by Dan Potter
* Fixes for libbfd segfaults by Atani
* Inspiration for MAPL packet by Tim Hentenaar