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+6502
+====
+
+The cpu/6502/ directory is used for targeting 6502-based machines using the
+cc65 compiler [http://www.cc65.org](http://www.cc65.org).
+
+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.a2retrosystems.com/contiki.html)
+- [http://contiki.cbm8bit.com](http://contiki.cbm8bit.com)
+
+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 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.
+
+- CONNECTIONS
+    - Default: 10
+    - Purpose: Set the maximum number of concurrent TCP connections.
+
+- WITH_LOGGING
+    - Default: 0
+    - Purpose: Have log_message() and UIP_LOG() 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.