From @mail.uunet.ca:beejay@micor Mon Dec  7 00:37:00 1992
Received: from calvin.sfasu.edu by umaxc.weeg.uiowa.edu (5.61.jnf/920629)
	  on Mon, 7 Dec 92 00:36:57 -0600 id AA10689 with SMTP 
Received: from mail.uunet.ca (uunet.ca) by calvin.sfasu.EDU with SMTP (5.59/25-eef)
	id AA04123; Mon, 7 Dec 92 00:32:56 CST
Return-Path: <@mail.uunet.ca:beejay@micor>
Received: from ocunix by mail.uunet.ca with UUCP id <9864>; Mon, 7 Dec 1992 01:29:18 -0500
Received: by micor.OCUnix.On.Ca (smail2.5)
	id AA20910; 7 Dec 92 00:13:11 EST (Mon)
To: hyperc-l@calvin.sfasu.edu
Subject: Re:C quiz
Date: 	Sun, 6 Dec 1992 19:13:11 -0500
Message-Id: <9212070013.AA20907@micor.OCUnix.On.Ca>
From: beejay@micor.ocunix.on.ca (Basil Johnson)
Status: R

 
ST2975@SIUCVMB.SIU.EDU writes:
 
>I think I got this to work with a minimum of
>manipulation.  Don't ask me why I did what I did.
>
>:-)
 
I won't. :-)  Yes, it works!  I was seeking analysis 
not alternatives, but I'll take it.  However, I'm still 
looking for an explanation.  Perhaps you could comment 
on the different '.s' code produced for the inkey() 
function in the following three situations.
 
----------This is from the original quiz--------------
     .entry    _inkey
_inkey:   .lbl
     lnk  2
     pdc  1
     jsr  2,_getkey
     stb  _1
     pdb  _1
     pea  _2
     jsr  4,_printf
     pdc  -16287
     pea  _3
     jsr  4,_printf
     ldc  -16287
     lib  0               ******
     lbit -127,97         *** is 97 the lsb of 0xc061? ***
     slb  -1
     plb  -1
     pea  _4
     jsr  4,_printf
     llb  -1
     ldcb 128
     jult _5
     ldb  _1
     inc  128
     stb  _1
     ldw  _trace_sw
     ldcb 1
     jne  _6
     ldc  0
     stw  _trace_sw
     jmp  _7
_6:  .lbl
     ldc  1
     stw  _trace_sw
_7:  .lbl
_5:  .lbl
     ldb  _1
     rtn
 
------------This is from your solution----------------
     .entry    _inkey
_inkey:   .lbl
     lnk  2
     pdc  1
     jsr  2,_getkey
     stb  _1
     pdb  _1
     pea  _2
     jsr  4,_printf
     pdc  -16287
     pea  _3
     jsr  4,_printf
     ldc  -16287
     slw  -2
     psh
     pea  _4
     jsr  4,_printf
     llw  -2
     ldcb 128
     jult _5
     ldb  _1
     inc  128
     stb  _1
     ldw  _trace_sw
     ldcb 1
     jne  _6
     ldc  0
     stw  _trace_sw
     jmp  _7
_6:  .lbl
     ldc  1
     stw  _trace_sw
_7:  .lbl
_5:  .lbl
     ldb  _1
     rtn
 
----This is the same as original but uses an assembly lang peekb -----
     .entry    _inkey
_inkey:   .lbl
     lnk  2
     pdc  1
     jsr  2,_getkey
     stb  _1
     pdb  _1
     pea  _2
     jsr  4,_printf
     pdc  -16287
     pea  _3
     jsr  4,_printf
     pdc  -16287
     jsr  2,_peekb
     slb  -1
     plb  -1
     pea  _4
     jsr  4,_printf
     llb  -1
     ldcb 128
     jult _5
     ldb  _1
     inc  128
     stb  _1
     ldw  _trace_sw
     ldcb 1
     jne  _6
     ldc  0
     stw  _trace_sw
     jmp  _7
_6:  .lbl
     ldc  1
     stw  _trace_sw
_7:  .lbl
_5:  .lbl
     ldb  _1
     rtn
 
The problem lies between the 2nd and 3rd jsr  4, printf.  When I changed the 
#define OA_KEY 0xc061 to the explicit declaration unsigned OA_KEY = 0xc061; 
the program worked OK.  So the problem is not with the macro.  
Here's the code that that version generated and a comparison with the first.
 
     jsr  4, printf
     llw  -2             (not in the incorrect version)
     lib  0
                         (lbit  -127, 97 in the incorrect version)
     slb  -3             (slb  -1)
     plb  -3             (plb  -1)
     pea  _4
     jsr  4, printf
 
I'm not familiar enough with the opcodes to decipher what's happening.
However, since one can't do '#define unsigned OA_KEY 0xc061', my guess 
is that either #define does not accept an unsigned integer (what do the 
gurus say) or HyperC is generating incorrect code in this instance.  
Looks like I am getting 0x7f61 instead of 0xc061.  
 
So, is this a bug? 
 
Basil Johnson           UUCP: micor!beejay        |Oh, Fate! ...
Nepean, Ontario         InterNet:                 |Such a stupid thing:
CANADA  K2B 8E9         beejay@micor.ocunix.on.ca |Command a bird to fly
(613) 820-0804                                    |Then clip its wing!
--