NASM - The Netwide Assembler

NASM Forum => Programming with NASM => Topic started by: RuudB on January 22, 2019, 11:30:02 AM

Title: Using graphical characters
Post by: RuudB on January 22, 2019, 11:30:02 AM

Hello,

I'm writing my own diagnostic ROM for the IBM-PC/XT and I want to draw a box that represents the on board dip switch block(s). So I used '<causes database error???>'  as top of the blocks of the IBM-PC and my screen went black. Checking the LST I found that Nasm had translated each grahical char to three bytes. The only thing I can guess is that it has to do with UTF. I checked the manual but unfortunately that didn't make me any wiser.

OK, I found a work around by using ' db 191, 191, 196' etc. but I still would like to know if I can use graphical characters as I intended to and, if yes, how.

Thank you very much in advance!

EDIT: even the forum software has problems with these characters. I just hope you understand which characters I mean.

Kind regards, Ruud Baltissen

Title: Re: Using graphical errors
Post by: Frank Kotler on January 22, 2019, 09:55:10 PM

Hi Ruud,

"True ascii" characters are 7 bit - that is, 0 to 127. The characters you mention mayt be called "high ascii" (there's really no such thing). They may be part of an ansi standard(?) - which may work on some systems but not all - such as the forum software, You may be stuck with unicode/utf, I can't tell you much about that.

These are the first references I found:

https://en.wikipedia.org/wiki/Box-drawing_character

jrgraphix.net/r/Unicode/2500-257F

You've  probably already seen them. Wish I could help you more!

Best,
Frank

Title: Re: Using graphical characters
Post by: RuudB on January 24, 2019, 10:56:42 AM

> jrgraphix.net/r/Unicode/2500-257F

At least this page explains the code I see in the LST file. NASM does its job correctly but the poor old IBM doesn't understand it :)

Many thanks!

Kind regards, Ruud Baltissen