The cpu/6502/ directory is used for targeting 6502-based machines using the cc65
compiler (http://www.cc65.org/). In almost all cases it is preferable to go for
a recent snapshot instead of the latest official version. The most recent cc65
snapshot is available at ftp://ftp.musoftware.de/pub/uz/cc65/snapshot/.


The Contiki network configuration for 6502-based targets is loaded from a binary
configuration file (by default named contiki.cfg). It has the following format:

- Bytes  1 -  4: IP Address     (HiByte first)
- Bytes  5 -  8: Subnet Mask    (HiByte first)
- Bytes  9 - 12: Default Router (HiByte first)
- Bytes 13 - 16: DNS Server     (HiByte first)
- Bytes 17 - 18: Ethernet card I/O address (LoByte first !)
- Bytes 19 - xx: Ethernet card driver name (ASCII / PETSCII)

An online Contiki configuration file generator is available at two sites:

- http://www.a2retrosystems.com/contiki.html
- http://www.cbm8bit.com/contiki/


The build for 6502-based machines includes the 'disk' make goal which creates a
bootable floppy disk image containing the project binary, a sample configuration
file and the Ethernet card drivers.


The 6502-based targets do in general not support keyboard input or screen output
through stdin, stdout and stderr.


The build for 6502-based machines supports so-called high-level configuration
macros which allow to customize Contiki on a per-project basis. They are set
in form of a comma-separated list as value of the make variable DEFINES on the
make command line. The value of DEFINES can be saved with the 'savedefines' make
goal. The values of the high-level configuration macros are not tracked by the
build so a manual rebuild is necessary on any change. The following high-level
configuration macros may be set:

MTU_SIZE
- Default: 1500
- Purpose: Set the Maximum Transfer Unit size.

WITH_LOGGING
- Default: 0
- Purpose: Have log_message() write messages to the screen.

WITH_BOOST
- Default: 0
- Purpose: Significantly improve troughput on sending full sized packets by
           splitting them thus workarounding the "delayed acknowledge".

WITH_FORWARDING
- Default: 0
- Purpose: Enable support for the 'IP forwarding' packet driver.

WITH_CLIENT
- Default: 0
- Purpose: Enable support for outgoing TCP connections.

WITH_DNS
- Default: 0
- Purpose: Enable UDP support and initialize resolver process on startup.

WITH_GUI
- Default: 0
- Purpose: Initialize the the CTK process on startup.

WITH_MOUSE
- Default: 0
- Purpose: Enable CTK mouse support and load a mouse driver.

WITH_PFS
- Default: 0
- Purpose: Implement the CFS interface with a Platform-specific File System
           instead of the POSIX file system.
