Small C for the Motorola 68xx family under Linux.
I am on a quest for a Small C compiler to support the various 6800/6803/6809/68000 boards I have. So with that in mind I am posting my notes and everything else I find on Small C. So for a while this will be quite a mess.
Ron Cain's 1.1 Small C compiler for the 6800, 6801, 6803 and 6809. Maybe the 68HC11. The original Author of the Flex port is S. Stepanoff
Originally these were Flex OS Compilers but I think I can make this work under Linux and the output code should be OS agnotic. My intention is to set them up to work on Linux as a cross-compiler.
There are currently 3 sets of source code for the Small C compiler. The 6800 version (a C to peudo code compiler), the silifen version (looks like a C to asm code compiler), and the v22 version (MSDOS C to executable).
6800/ ..... Early version of the Flex OS Small C compiler (very limitted, v1.1 1982)
silifen/ .. Later version of the Flex OS Small C compiler (has for(), etc v2.1 1985)
v22/ ...... MSDOS version of the Small C compiler (v2.2, outputs 8086 code)
MicroC/ ... Dave Dunfield's Micro C (CUG422_* DOS Binaries)
LICENSE ... Proposed License (I may need to change this)
Makefile .. Ignore this, make files have moved their respective directories
README.md . This file
ccint.txt . Ignore this file (Small C interpreter used in 6800 version)
After reading and poking around the Flex Small C Compiler DSK images I've guessed that these are Ron Cain's Small C V1.1 compiler and that the runXX (00,01,09) are the runtime files that take the psuedo code and make it understandable (assemble) under Flex.
The ccx.c files is the smallc.c file broken into 9 sections so the small C compiler can compile itself on Flex. Since I'll be using Linux to cross compile. I'll not include this files.
cc0.c
cc1.c
cc2.c
cc3.c
cc4.c
cc5.c
cc6.c
cc7.c
cc8.c
The important file is smallc.c, that's my starting point. The p.c file is a C pre-processor. I'm not sure if I'll use it but decided to keep it here for now. The rest of the files are files needed to assemble the psuedo code generated by the small C compiler. At this time I'm not sure which is which. I'll work on that.
ccc.h
ccint.txt
flexptrs.txt
LICENSE
p.c
prtlib.asm
prtlib.c
prtlib.lib
README.md
run1.asm
run9.asm
run9.c
smallc.c
2023/02/04 - I've got the compiler hacked together and mostly working. What I've found is that the small c compiler outputs pseudo code and that the run9 (6809) and run1 (6801) code are the asm source to an interpreter. Assemble the code together and you have a program. This small C compiler is still quite limitted but may be useful and as one of the notes files points out C is easier to write than asm code. Anyway I'm posting this mess so I don't lose it and so other might get ideas. Just note that this is terrible C code. It was meant to use the very limmited small c compiler to compile itself. I'm in the process of making it work under Linux as a cross compiler for any of the Motorola preocessors. It will no longer compiler itself.
http://www.pennelynn.com/Documents/CUJ/HTML/90HTML/199000DA.HTM A Survey Of CUG C Compilers by Victor Volkman https://archive.org/details/cug995 C Users' Group CDROM, September 1995 edition https://github.com/linuxha/asl ASL Macro assembler https://github.com/EtchedPixels/CC6303 A C compiler for the 6800/6803/6303 processors https://github.com/aladur/flexemu - 6809 Flex OS Emulator for Linux & Windows https://hackaday.io/project/189491-small-c-68xx - Hackaday project
Summary of CUG C Compilers
Target Implementation
CUG Target Operating Based on Port Date of Last Overall
Disk # CPU System From Revision Rating
------------------------------------------------------------------------
104 Z-80/8080 CP/M 80 v2.2 RC Small C v1.1 06/28/1981 ***
132 6809 0S-9 RC Small C v1.1 10/18/1983 **
146 6800 FLEX v2.1 RC Small C v1.1 09/09/1982 **
156 Z-80 CP/M RC Small C v1.2 08/02/1984 ****
163 8086 PC-DOS 1.1 JH Small C v2.0 01/14/1984 ***
170 8086 PC-DOS 1.0 RC Small C v1.0 06/01/1982 *
204 68000 Unix V N/A 01/01/1986 ****
221 6809 FLEX RC Small C v1.0 11/15/1986 ***
243 8086 PC-DOS 2.0 DECUS 12/01/1985 N/A