About Kernel

This is a hard-realtime message passing kernel with

• preemptive multitasking
• multiple priorities (round-robin within a single priority)
• timers
• dynamic memory manager
• a low-priority memory compacting task
• a cblock-based character device driver interface

and not much else.

It's written in C++ (g++) for the TMS34010.  There's also infrastructure for the Motorola 68000, although I haven't used that for a while.  This kernel should be quite portable, given that the 34010 is little-endian and the 68k is big-endian. The 68k-specific code is only 130 lines.

The realtime kernel source is in the lib/libk/ directory of the 34010 source tree, available here.

A TMS34010 development system

The Texas Instruments 34010 is a discontinued 32 bit CISC microprocessor with an on-board graphics engine.

The 34010 is quite bizarre in that it is bit addressable: to advance a pointer by a byte you must add eight to it. When I discussed this with Richard Stallman he said that gcc would cope with it easily.  He was wrong - at all levels gcc is littered with the assumption that

char *p;
p = p + 1;

and

char *p
p = (char *)((long)p + 1);

are equivalent.

This development system includes a port of gcc and g++ (2.5.8), a YACC-based assembler, a linker, an archiver, an nm equivalent, a disassembler, a download utility and various other bits and pieces.

The 34k development system may be accessed here.