/ Developer CD Series 1996 June: Reference Library / Dev.CD Jun 96 RL / Dev.CD Jun 96 RL.toast / Technical Documentation / develop / develop Issue 8 / develop Issue 8 code / Macintosh Debugging.sea / Macintosh Debugging / EvenBetterBusError / EvenBetterBusError Readme

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MacOS 8.1

Win98

DOS

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+--------+-------------------------+-------------------------+--------+--------+
|00000000| 00 19 45 76 65 6e 42 65 | 74 74 65 72 42 75 73 45 |..EvenBe|tterBusE|
|00000010| 72 72 6f 72 20 52 65 61 | 64 6d 65 00 00 00 00 00 |rror Rea|dme.....|
|00000020| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00000030| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00000040| 00 54 45 58 54 4d 50 53 | 20 01 00 00 00 00 00 00 |.TEXTMPS| .......|
|00000050| 00 00 00 00 00 05 e9 00 | 00 01 ac a5 19 52 cb a5 |........|.....R..|
|00000060| 19 52 cb 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |.R......|........|
|00000070| 00 00 00 00 00 00 00 00 | 00 00 81 81 92 5b 00 00 |........|.....[..|
|00000080| 45 76 65 6e 42 65 74 74 | 65 72 42 75 73 45 72 72 |EvenBett|erBusErr|
|00000090| 6f 72 20 2d 20 61 20 73 | 79 73 74 65 6d 20 65 78 |or - a s|ystem ex|
|000000a0| 74 65 6e 73 69 6f 6e 20 | 74 6f 20 68 65 6c 70 20 |tension |to help |
|000000b0| 63 61 74 63 68 20 72 65 | 6e 65 67 61 64 65 20 72 |catch re|negade r|
|000000c0| 65 66 65 72 65 6e 63 65 | 73 20 74 6f 20 4e 49 4c |eference|s to NIL|
|000000d0| 2e 2e 2e 0d 0d 4d 61 6e | 79 20 6f 66 20 79 6f 75 |.....Man|y of you|
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|000000f0| 72 2e 20 42 75 73 45 72 | 72 6f 72 2c 20 61 20 73 |r. BusEr|ror, a s|
|00000100| 79 73 74 65 6d 20 65 78 | 74 65 6e 73 69 6f 6e 20 |ystem ex|tension |
|00000110| 64 65 73 69 67 6e 65 64 | 20 74 6f 20 68 65 6c 70 |designed| to help|
|00000120| 20 63 61 74 63 68 20 70 | 72 6f 67 72 61 6d 73 20 | catch p|rograms |
|00000130| 74 68 61 74 0d 64 65 2d | 72 65 66 65 72 65 6e 63 |that.de-|referenc|
|00000140| 65 20 4e 49 4c 20 28 74 | 68 69 6e 6b 69 6e 67 20 |e NIL (t|hinking |
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|00000170| 20 4d 72 2e 20 42 75 73 | 45 72 72 6f 72 20 70 65 | Mr. Bus|Error pe|
|00000180| 72 69 6f 64 69 63 61 6c | 6c 79 20 77 72 69 74 65 |riodical|ly write|
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|000001c0| 64 2c 20 77 69 6c 6c 20 | 63 61 75 73 65 20 61 20 |d, will |cause a |
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|000001e0| 72 65 73 73 20 65 72 72 | 6f 72 2e 20 20 41 63 74 |ress err|or.  Act|
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|00000230| 20 7a 65 72 6f 20 77 69 | 6c 6c 20 6f 6e 6c 79 20 | zero wi|ll only |
|00000240| 63 61 75 73 65 20 62 75 | 73 20 65 72 72 6f 72 73 |cause bu|s errors|
|00000250| 20 6f 6e 20 6d 61 63 68 | 69 6e 65 73 0d 72 75 6e | on mach|ines.run|
|00000260| 6e 69 6e 67 20 69 6e 20 | 32 34 2d 62 69 74 20 6d |ning in |24-bit m|
|00000270| 6f 64 65 2e 20 20 49 74 | 20 64 6f 65 73 6e 27 74 |ode.  It| doesn't|
|00000280| 20 63 61 75 73 65 20 61 | 20 62 75 73 20 65 72 72 | cause a| bus err|
|00000290| 6f 72 20 69 6e 20 33 32 | 2d 62 69 74 20 6d 6f 64 |or in 32|-bit mod|
|000002a0| 65 2e 0d 0d 53 6f 2c 20 | 61 6c 6f 6e 67 20 63 6f |e...So, |along co|
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|00000320| 6c 75 65 20 69 74 20 73 | 74 75 66 66 73 20 69 6e |lue it s|tuffs in|
|00000330| 74 6f 20 6c 6f 63 61 74 | 69 6f 6e 20 7a 65 72 6f |to locat|ion zero|
|00000340| 20 69 73 20 61 20 22 62 | 61 64 22 20 61 64 64 72 | is a "b|ad" addr|
|00000350| 65 73 73 20 69 6e 20 33 | 32 2d 62 69 74 0d 6d 6f |ess in 3|2-bit.mo|
|00000360| 64 65 20 61 73 20 77 65 | 6c 6c 20 61 73 20 32 34 |de as we|ll as 24|
|00000370| 2d 62 69 74 20 6d 6f 64 | 65 2e 20 20 53 65 63 6f |-bit mod|e.  Seco|
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|00000390| 6b 73 20 74 6f 20 73 65 | 65 20 69 66 20 61 6e 79 |ks to se|e if any|
|000003a0| 6f 6e 65 20 68 61 73 20 | 77 72 69 74 74 65 6e 20 |one has |written |
|000003b0| 64 61 74 61 20 74 6f 20 | 6c 6f 63 61 74 69 6f 6e |data to |location|
|000003c0| 0d 7a 65 72 6f 20 28 61 | 6e 6f 74 68 65 72 20 63 |.zero (a|nother c|
|000003d0| 6f 6d 6d 6f 6e 20 70 72 | 6f 67 72 61 6d 6d 69 6e |ommon pr|ogrammin|
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|000003f0| 66 61 72 2c 20 73 6f 20 | 67 6f 6f 64 2e 2e 2e 0d |far, so |good....|
|00000400| 0d 57 65 6c 6c 2c 20 75 | 6e 66 6f 72 74 75 6e 61 |.Well, u|nfortuna|
|00000410| 74 65 6c 79 2c 20 74 68 | 65 20 6d 65 6d 6f 72 79 |tely, th|e memory|
|00000420| 20 6d 61 6e 61 67 65 72 | 20 69 6e 20 74 68 65 20 | manager| in the |
|00000430| 33 32 2d 62 69 74 20 63 | 6c 65 61 6e 20 52 4f 4d |32-bit c|lean ROM|
|00000440| 73 20 68 61 73 20 61 20 | 62 75 67 20 77 68 69 63 |s has a |bug whic|
|00000450| 68 20 63 61 75 73 65 73 | 20 69 74 20 74 6f 20 0d |h causes| it to .|
|00000460| 77 72 69 74 65 20 74 6f | 20 6c 6f 63 61 74 69 6f |write to| locatio|
|00000470| 6e 20 7a 65 72 6f 20 65 | 76 65 72 79 20 74 69 6d |n zero e|very tim|
|00000480| 65 20 53 65 74 50 74 72 | 53 69 7a 65 20 69 73 20 |e SetPtr|Size is |
|00000490| 63 61 6c 6c 65 64 20 77 | 68 69 6c 65 20 72 75 6e |called w|hile run|
|000004a0| 6e 69 6e 67 20 69 6e 20 | 32 34 2d 62 69 74 20 6d |ning in |24-bit m|
|000004b0| 6f 64 65 2e 20 20 54 68 | 69 73 20 63 61 75 73 65 |ode.  Th|is cause|
|000004c0| 73 0d 42 65 74 74 65 72 | 42 75 73 45 72 72 6f 72 |s.Better|BusError|
|000004d0| 20 74 6f 20 62 72 65 61 | 6b 20 69 6e 74 6f 20 74 | to brea|k into t|
|000004e0| 68 65 20 64 65 62 75 67 | 67 65 72 20 73 68 6f 75 |he debug|ger shou|
|000004f0| 74 69 6e 67 20 d2 57 72 | 69 74 65 20 74 6f 20 4e |ting .Wr|ite to N|
|00000500| 49 4c 21 d3 2e 20 20 41 | 63 74 75 61 6c 6c 79 2c |IL!..  A|ctually,|
|00000510| 20 69 74 27 73 20 6f 6e | 6c 79 20 74 68 65 0d d2 | it's on|ly the..|
|00000520| 68 69 67 68 d3 20 62 69 | 74 20 6f 66 20 74 68 65 |high. bi|t of the|
|00000530| 20 6c 6f 6e 67 20 61 74 | 20 6c 6f 63 61 74 69 6f | long at| locatio|
|00000540| 6e 20 7a 65 72 6f 20 77 | 68 69 63 68 20 69 73 20 |n zero w|hich is |
|00000550| 63 68 61 6e 67 65 64 20 | 28 74 68 65 20 6d 65 6d |changed |(the mem|
|00000560| 6f 72 79 20 6d 61 6e 61 | 67 65 72 20 69 73 20 d2 |ory mana|ger is .|
|00000570| 6c 6f 63 6b 69 6e 67 d3 | 20 74 68 65 0d d2 68 61 |locking.| the..ha|
|00000580| 6e 64 6c 65 d3 20 28 77 | 68 69 63 68 20 69 73 6e |ndle. (w|hich isn|
|00000590| d5 74 20 74 68 65 72 65 | 2e 2e 2e 29 2e 0d 0d 45 |.t there|...)...E|
|000005a0| 76 65 6e 42 65 74 74 65 | 72 42 75 73 45 72 72 6f |venBette|rBusErro|
|000005b0| 72 20 28 45 42 42 45 29 | 20 74 6f 20 74 68 65 20 |r (EBBE)| to the |
|000005c0| 72 65 73 63 75 65 21 20 | 20 45 42 42 45 20 64 6f |rescue! | EBBE do|
|000005d0| 65 73 20 65 76 65 72 79 | 74 68 69 6e 67 20 74 68 |es every|thing th|
|000005e0| 65 20 6f 74 68 65 72 20 | 74 77 6f 20 65 78 74 65 |e other |two exte|
|000005f0| 6e 73 69 6f 6e 73 20 64 | 6f 2c 0d 61 6e 64 20 61 |nsions d|o,.and a|
|00000600| 6c 73 6f 20 6b 6e 6f 77 | 73 20 74 6f 20 69 67 6e |lso know|s to ign|
|00000610| 6f 72 65 20 74 68 65 20 | 68 69 67 68 20 62 69 74 |ore the |high bit|
|00000620| 20 61 74 20 7a 65 72 6f | 20 73 69 6e 63 65 20 74 | at zero| since t|
|00000630| 68 65 20 6d 65 6d 6f 72 | 79 20 6d 61 6e 61 67 65 |he memor|y manage|
|00000640| 72 20 77 69 6c 6c 20 63 | 68 61 6e 67 65 20 69 74 |r will c|hange it|
|00000650| 2e 2e 2e 0d 0d 45 6e 6a | 6f 79 2e 0d 47 72 65 67 |.....Enj|oy..Greg|
|00000660| 20 4d 61 72 72 69 6f 74 | 74 00 00 00 00 00 00 00 | Marriot|t.......|
|00000670| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00000680| 00 00 01 00 00 00 01 6e | 00 00 00 6e 00 00 00 3e |.......n|...n...>|
|00000690| 57 46 30 31 54 48 30 32 | 01 00 00 00 00 00 00 00 |WF01TH02|........|
|000006a0| fd d0 01 00 0b 01 57 46 | 30 31 54 48 30 33 01 00 |......WF|01TH03..|
|000006b0| 19 45 76 65 6e 42 65 74 | 74 65 72 42 75 73 45 72 |.EvenBet|terBusEr|
|000006c0| 72 6f 72 20 52 65 61 64 | 6d 65 02 00 00 00 54 45 |ror Read|me....TE|
|000006d0| 00 00 54 45 58 54 4d 50 | 53 20 01 00 00 34 00 40 |..TEXTMP|S ...4.@|
|000006e0| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|000006f0| 00 00 a4 25 4c 47 00 00 | 05 e9 00 00 01 ac 57 49 |...%LG..|......WI|
|00000700| 4c 44 53 54 41 4b 01 00 | 00 00 00 00 00 00 63 84 |LDSTAK..|......c.|
|00000710| 01 00 0b 01 57 49 4c 44 | 70 61 75 6c ff 00 00 00 |....WILD|paul....|
|00000720| 00 00 00 00 64 84 00 04 | 0b 01 58 43 45 4c 41 50 |....d...|..XCELAP|
|00000730| 50 4c 01 00 00 00 00 00 | 00 00 7a bc 01 00 0b 01 |PL......|..z.....|
|00000740| 58 43 45 4c 4d 43 42 4e | 01 00 00 00 00 00 00 00 |XCELMCBN|........|
|00000750| 82 bc 01 00 0b 01 58 43 | 45 4c 58 4c 42 4e 01 00 |......XC|ELXLBN..|
|00000760| 00 00 00 00 00 00 81 bc | 01 00 0b 01 58 43 45 4c |........|....XCEL|
|00000770| 58 4c 43 20 01 00 00 00 | 00 00 00 00 7d bc 01 00 |XLC ....|....}...|
|00000780| 00 00 00 48 00 09 4d 6f | 6e 61 63 6f 00 00 02 b6 |...H..Mo|naco....|
|00000790| 00 00 00 a4 00 01 ed 24 | 00 0a 01 13 01 8f 01 1e |.......$|........|
|000007a0| 01 90 01 13 00 00 00 06 | 00 04 00 2c 00 07 01 8c |........|...,....|
|000007b0| 02 7b 00 2c 00 07 01 8c | 02 7b a4 f5 38 78 00 00 |.{.,....|.{..8x..|
|000007c0| 01 f6 00 00 01 f6 00 00 | 00 00 01 00 00 00 00 1e |........|........|
|000007d0| 00 2c 00 07 01 8c 02 7b | 00 2c 00 07 01 8c 02 7b |.,.....{|.,.....{|
|000007e0| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|000007f0| 01 00 00 00 01 6e 00 00 | 00 6e 00 00 00 3e 00 4d |.....n..|.n...>.M|
|00000800| 13 a0 0b c2 00 00 00 1c | 00 3e 00 00 4d 50 53 52 |........|.>..MPSR|
|00000810| 00 01 00 0a 03 ed ff ff | 00 00 00 00 00 00 00 00 |........|........|
|00000820| 03 f0 ff ff 00 00 00 4c | 00 4f 14 b8 00 00 00 00 |.......L|.O......|
|00000830| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00000840| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00000850| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00000860| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
|00000870| 00 00 00 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |........|........|
+--------+-------------------------+-------------------------+--------+--------+