Re: [BLACKBOX] Ofront supporting for unsigned types

From: [at]} <Chris>
Date: Thu, 26 Apr 2012 21:38:00 +0930

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>-----Original Message-----
>From: BlackBox [mailto:BLACKBOX{([at]})nowhere.xy
>Oleg N. Cher
>Sent: Thursday, 26 April 2012 3:59 AM
>To: BLACKBOX{([at]})nowhere.xy
>Subject: [BLACKBOX] Ofront supporting for unsigned types
>
>
>You certainly know that for such weak CPU as 6502 (or Z80)
>unsigned arithmetic is not luxury, but absolute necessary.
>Every C developers says me: "For loop with counter from 0 to
>255 I've used in C one-byte variable, and you in Oberon must
>use two-byte. Oberon is bad and ugly".
>Especially this possibly is need for two-byte comparsions and
>some other arithmetic operations.

Attempting to target an 8-bit CPU with a higher-level like Oberon is likely
to lead to disappointment - it wasn't designed with such targets in mind.

A couple of years ago I was also affected by the nostalgia bug and rebuilt
an 8-bit SBC that I first worked with 30 years ago. It has a Signetics S2650
CPU and a maximum of 4K of RAM. However, I had no interest in programming it
with C or Oberon even if it had been possible. Satisfaction was gained from
having complete control over the processor by programming it in assembler.

For a description of a better fit between a language and a comparatively
primitive CPU read the report for the "PICL" language that Wirth developed
for programming the PIC 8-bit microcontroller. He introduces it with:

"Here we present a programming language ***that is tailored to the PIC's
size and architecture***. The challenge lay in postulating a design allowing
to abstract from the peculiarities of the particular architecture and
overcome the tedium of coding instruction by instruction with an assembler,
and yet of letting the processor's facilities
be sufficiently transparent, that no excessively inefficient programs will
be produced."

http://www.inf.ethz.ch/personal/wirth/Articles/Miscellaneous/index.html

Regards,
Chris Burrows

CFB Software
Astrobe v4.1: Oberon for Cortex-M3 Microcontrollers
http://www.astrobe.com

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Received on Thu Apr 26 2012 - 14:08:00 UTC