Re: [BLACKBOX] Ofront supporting for unsigned types

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

----boundary-LibPST-iamunique-1966331975_-_-
Content-type: text/plain

>-----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


----
To unsubscribe, send a message with body "SIGNOFF BLACKBOX" to LISTSERV{([at]})nowhere.xy----boundary-LibPST-iamunique-1966331975_-_-
Content-type: application/rtf
Content-transfer-encoding: base64
Content-Disposition: attachment; filename="rtf-body.rtf"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----boundary-LibPST-iamunique-1966331975_-_---
Received on Thu Apr 26 2012 - 14:08:00 UTC

This archive was generated by hypermail 2.3.0 : Thu Sep 26 2013 - 06:30:03 UTC