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ea08635ca4
nes-proj/cpu/6502
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Oliver Schmidt ea08635ca4 Optimized CS8900A driver for speed and size. 
- Speed: The primary byte copy loops are reduzed to the bare minimum by adjusting the base pointer 'ptr' and loop register 'y' in such a way that the 'y' overflow matches the low byte of the loop size.

- Size: Factored out all repeated code into subroutines. Introduced a loop for setting the MAC address.

Additional minor changes:

- Activate frame reception as last step of initialization after CS8900A configuration.

- Properly set internal address bits used by the CS8900A.
2013-09-12 23:32:25 +02:00
..
ctk Remove tab chars from retro C sources. 2013-01-28 23:43:08 +01:00
ipconfig Another small addition for platform 'Atari XL'. 2013-06-02 23:36:28 +02:00
lib Remove tab chars from retro C sources. 2013-01-28 23:43:08 +01:00
net Optimized CS8900A driver for speed and size. 2013-09-12 23:32:25 +02:00
sys Removed some more old RCS tags from the Contiki source tree. 2013-06-13 15:54:26 +02:00
6502def.h Added configurations of the new resolver. 2013-03-14 23:17:59 +01:00
Makefile.6502 Suppress some usual warnings. 2013-07-31 00:29:52 +02:00
README.md Several minor consistency improvements. 2013-07-31 00:55:31 +02:00

README.md

6502

The cpu/6502/ directory is used for targeting 6502-based machines using the cc65 compiler http://oliverschmidt.github.io/cc65/.

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:

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.