Groups > comp.sys.apple2.programmer > #4997

Re: Call Address to Print BASIC Error Message

Newsgroups	comp.sys.apple2.programmer
Date	2019-02-03 10:19 -0800
References	<f52655a8-0fd6-4aee-b345-8631bb8b3b38@googlegroups.com> <2b9c4542-55b8-4f71-97d1-e0b5ad57b5b4@googlegroups.com> <yubpnsaavnc.fsf@gmail.com> <q35op4$ouf$1@dont-email.me>
Message-ID	<a633aa85-3b85-43df-bb6b-e34e21daebbe@googlegroups.com> (permalink)
Subject	Re: Call Address to Print BASIC Error Message
From	gids.rs@sasktel.net

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On Saturday, February 2, 2019 at 9:56:21 PM UTC-6, Jeff Blakeney wrote:
> On 2019-02-02 1:32 p.m., awanderin wrote:
> > Here's an all-Applesoft way to do it.  Substitute your choice of error
> > on line 20...
> > 
> > 10  ONERR  GOTO 1000
> > 20  PRINT 1 / 0 : REM Generate error
> > 30  END
> > 1000 BE = 53856
> > 1010 EA = BE +  PEEK (222)
> > 1015  GOSUB 1050
> > 1020 EA = BE + 240: GOSUB 1050
> > 1030  PRINT " IN LINE " PEEK (218) + 256 *  PEEK (219)
> > 1040  END
> > 1050 C =  PEEK (EA): IF C > 0 AND C < 128 THEN  PRINT  CHR$ (C);:EA = EA + 1: GOTO 1050
> > 1055  IF C >  = 128 THEN  PRINT  CHR$ (C);
> > 1060  RETURN
> 
> Just curious why you are checking for C being from 1 to 127 and then 
> later checking to see if it is greater than 127.  In both cases you are 
> printing CHR$(C).
> 
> C will always be between 0 and 255 so the first check could be reduced 
> to just "IF C < 128 THEN PRINT CHR$(C);".
> 
> I'm assuming you did this to avoid printing the high ASCII last 
> character so line 1055 should probably be "IF C > 127 THEN PRINT 
> CHR$(C-128);".  However, as we know that the condition that exits the 
> loop is that C is greater than 127 all you really need on line 1055 is 
> "PRINT CHR$(C-128);".


No need to duplicate the CHR$(C)or have multiple lines.

1050 C= PEEK(EA): PRINT CHR$(C): EA = EA + 1: ON C < 128 GOTO 1050: RETURN

Thread

Call Address to Print BASIC Error Message Bill Chatfield <billchatfield1@gmail.com> - 2019-01-30 15:16 -0800
  Re: Call Address to Print BASIC Error Message James Davis <JPD.Enterprises@outlook.com> - 2019-01-30 18:21 -0800
  Re: Call Address to Print BASIC Error Message gids.rs@sasktel.net - 2019-01-30 21:05 -0800
  Re: Call Address to Print BASIC Error Message Tom Porter <laseractiveguy@gmail.com> - 2019-01-31 00:35 -0800
    Re: Call Address to Print BASIC Error Message kegs@provalid.com (Kent Dickey) - 2019-01-31 21:58 -0600
      Re: Call Address to Print BASIC Error Message Michael Pohoreski <michael.pohoreski@gmail.com> - 2019-01-31 22:31 -0800
  Call Address to Print BASIC Error Message Michael Pohoreski <michael.pohoreski@gmail.com> - 2019-01-31 23:01 -0800
    Re: Call Address to Print BASIC Error Message awanderin <awanderin@gmail.com> - 2019-02-02 11:32 -0700
      Re: Call Address to Print BASIC Error Message Jeff Blakeney <CUTjeffrey_blakeney@yahoo.ca> - 2019-02-02 22:56 -0500
        Re: Call Address to Print BASIC Error Message gids.rs@sasktel.net - 2019-02-03 10:19 -0800
          Re: Call Address to Print BASIC Error Message Michael Barry <barrym95838@yahoo.com> - 2019-02-04 00:42 -0800
        Re: Call Address to Print BASIC Error Message Michael Barry <barrym95838@yahoo.com> - 2019-02-04 00:31 -0800
          Re: Call Address to Print BASIC Error Message Jeff Blakeney <CUTjeffrey_blakeney@yahoo.ca> - 2019-02-04 10:27 -0500
            Re: Call Address to Print BASIC Error Message Bill Chatfield <billchatfield1@gmail.com> - 2019-02-09 09:28 -0800
              Re: Call Address to Print BASIC Error Message Michael Pohoreski <michael.pohoreski@gmail.com> - 2019-02-09 13:57 -0800
      Re: Call Address to Print BASIC Error Message Michael Barry <barrym95838@yahoo.com> - 2019-02-04 01:06 -0800

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