8Mhz "On Semiconductors" 68008 runs at 12.5Mhz

From several sources I know that Motorola MC68k parts do not like to run on higher freqs then nominal.
At least that's not true for "On Semiconductors" parts.

Mathew Brandt's c68 and CP/M 68

While looking for C compiler for CP/M 68 looks I've found something that looks quite fine.
As for version "5.1 (beta)/25 Apr 2002" c68 taken from http://homepage.ntlworld.com/itimpi/compsrc.htm has
-cpm68 option and it somehow work. It even claims that it generates AS68compatible source.
There are a lot of versions of this compiler on the net, but this one is surely the best I've tried (but as I understand it's unable to compile itself, what a pity)
The way it does not work is writing hex as 0xXX, not as $XX, so here is a fix:
out68k_c.c:

PRIVATE void put_byte P1 (UVAL,val)
{        
    put_header (bytegen, alignment_of_type (tp_char));
    oprintf ("$%lx", (unsigned long) (val & OxffUL));
/*DtZ     oprintf ("0x%lx", (unsigned long) (val & OxffUL)); */
    outcol += 4; /* or  should be changed to +3 ? */
}

PRIVATE void put_word P1 (UVAL, val)
{
   put_header (wordgen, alignment_of_type (tp_short));
/*DtZ     oprintf ("0x%lx", (unsigned long) (val & OxffffUL)); */
    oprintf ("$%lx", (unsigned long) (val & OxffffUL));
    outcol += 6; /* or should be changed to +7? */
} 

Next, AS68 does not need/want "\t.sect", it accepts .data and .text directly.
out68k_c.c:

static void seg P3 (enum e_sg, segtype, const char *, segname, SIZE, al)
{
 nl();
 if (curseg != segtype) {                                                                                     
/*DtZ   oprintf ("\t.sect\t%s%s", segname, newline);*/                                                        
        oprintf ("\t%s * Segment %s", segname, newline);                                                       

And you should edit config.h the way it can generate for 68000 and to check the compiler binary you get can do -cpm68k and -int=16.
Next, remember that's just compiler, not even preprocessor: so on unix side I had to do
cc -E -I/home/dtz/8BIT/68K/CPM1.3/DISK4 main.c > p_main.c
./cc68 -int=16 -cpm68k -v p_main.c > main.s
Also, note that standard CP/M 68's headers lacks most of the C functions; so I had to copy them from "C language programming manual" (do not forget to add link link there!)
On CP/M system, assemble the file with AS68 -U file.o, and then link it with CLINK.SUB
UPD: More, the code it generates can be feed to jas assembler mentioned some time ago.
UPDD: Looks like optimization code is faulty.
UPDDD: 201607 Mirrored Here

Sozobon's JAS runs at CP/M 68K

As I expected, JAS from Sozobon C compiler for Atari was easy to port back to CP/M 68 and it works natively.
To do it, do the following: compile Sozobon C on unix host (see virtuallyfun.superglobalmegacorp.com/?p=97 (or mirrored on my site), then compile jas by xhcc, now using makefile , not make.unx.
First, make a small patch in main.c:

        if ( freopb( ofile, "w", stdout ) ==  NULL )
                error( 0, "can't open object file for writing" );
      if ( freopen( ofile, "bw", stdout ) == (FILE *) NULL )
             error( 0, "can't open object file for writing" );

Then take CP/M-68 1.3 distribution files; here you'll find DISK4 and header files on it. You have to convert them to lowercase and erase all symbols after (and including) ^Z.
Then edit makefile to became smth like that:

CC = ./xhcc
CFLAGS = -c -v -O -I/home/dtz/8BIT/68K/CPM1.3/DISK4

Run make, you'll get 10 *.s files; then assemble them by jas:

#!/usr/local/bin/tclsh
foreach f [glob *.s] {
 exec ./xjas -8 $f
}

You'll get 10 .o files. Transfer them to CP/M 68K host and link by DRI's LO68: c:lo68 -R -u_nofloat -o jas.68k c:s.o CBUF.O CPY.O GEN.O HDR.O LEX.O MAIN.O OPS.O OPT.O PARSE.O PASS.O SCAN.O SYM.O c:clib And know what? It works! (do not forget to add -8 switch when calling jas). However, that's not very useful as assembler, but better to have an assembler with SOURCE as alternative to AS68.
Get it from here ;-) [ok from here]

Use of Sozobon C on CP/M 68

I've tried to make some use of Sozobon C compiler to be somehow-used on[or together with] CP/M 68.
First, it can be compiled on modern Linux/MacOSX; that's good. And the thing that is useful is xjas assembler. At least with -8 flag it generates .o files with can be linked natively on CP/M'68 lo68.

And, what I say? I say: GOOOOOOOOOD!