[Oberon] Oberon on the Raspberry Pi

[Chris Burrows]

> -----Original Message-----
> From: Paul Onyschuk [mailto:blink at bojary.koba.pl]
> Sent: Friday, 11 April 2014 6:40 PM
> To: ETH Oberon and related systems
> Subject: Re: [Oberon] Oberon on the Raspberry Pi
> 
> As far I understand 16 opcodes are reserved by RISC architecture devised
by
> Prof. Wirth.  Common sense tells me (I could be wrong here, since I didn't
> read too much about compiler itself yet) that instructions could be stored
in
> nibble (half of byte), which is hard to beat when it comes to size of
object
> files.
> 

There are 16 register instructions (with an additional 5 modified forms), 2
memory instructions and 8 branch instructions. Every instruction is a 32-bit
word. You don't need to read about the compiler to find this out; the Wirth
RISC architecture used by the FPGA Oberon compiler is summarised in a 3 page
document:

http://www.inf.ethz.ch/personal/wirth/FPGA-relatedWork/RISC-Arch.pdf

Regards,
Chris 

--
Chris Burrows
CFB Software
http://www.cfbsoftware.com