11 Dec
2008
11 Dec
'08
11:27 a.m.
Dave Dunfield wrote:
You don't need register to register operations to
support a C compiler.
Can you provide any details of your architecture and instruction set?
It might be feasable to make a port of my Micro-C toolset to it... If
not, it might be feasable to make a port of "C-flea" a virtual machine
I designed specifically to support Micro-C (I've supported some pretty
weird architectures by employing C-flea).
The architecture is like I said before a stretched PDP-8, with a
512 byte direct addressing range and more compleate set of alu operations.
I am exploring the idea that 18 bits is still the best size word size
for a small
computer or digital controller. The extra opcode bit is used to
support word &
byte sized operands, compared to the that of a 8 bit micro. The two more
address
bits negate the loss of byte addressing and give a bit more room for a
resident
OS rather than swapping core in and out.
Using CPLD's also gives me the feel that a 18 bit simple cpu like my design
could have been developed as microchip computer similar to 6800 or 6502
chip set around the time the Z80 was developed. Using 48 rather 40 pins
as packaging a 18 bit cpu with front panel support could have been
developed.
A) Cpu chip. B) Swr/data/address bus display support chips . C)
data/byte swap buffer.
Micro-C is a very small, but reasonably powerful
dialect of C - For an
example, refer to the ImageDisk sources on my site ... ImageDisk and all
of it's utilities are compiled with the PC version of Micro-C (as are my
simulators, transfer tools and pretty much all of the other DOS based
tools I've posted).
Dave
Btw: If you haven't written an assembler yet, let me know - I've got a
universal table driven assembler generator which I developed to rapidly
produce assemblers for many of the later architectures I supported.
Unlikely it will work , I have 9 bit bytes.
I have hacked, Jones's PDP 8 assembler to cross assemble for me.
Once I get the the single PCB board built later next year, then I
will consider porting Micro-C. I plan to only have about 64Kb +
bootstrap EEPROM, IDE interface and a two 6850 uarts
along with a front panel. I am not sure yet if the IDE interface will be
16 or 9 bits wide yet.
--
dave06a (at) Dave Dunfield
dunfield (dot) Firmware development services & tools: www.dunfield.com
com Collector of vintage computing equipment:
http://www.classiccmp.org/dunfield/index.html