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| MacBinary | 1994-10-19 | 110.9 KB | [ONLN/HLX2] |
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This file was processed as: MacBinary
(archive/macBinary).
| Confidence | Program | Detection | Match Type | Support
|
|---|
| 10%
| dexvert
| MacBinary (archive/macBinary)
| fallback
| Supported |
| 100%
| file
| MacBinary II, inited, Tue Oct 4 11:00:08 1994, modified Wed Oct 19 07:57:29 1994, creator 'HLX2', type 'ONLN', 109870 bytes "HW23 FPU Operations on Quad" , at 0x1adae 3354 bytes resource
| default (weak)
| |
| 99%
| file
| data
| default
| |
| 100%
| TrID
| MacBinary 2
| default (weak)
| |
| 100%
| siegfried
| fmt/1762 MacBinary (II)
| default
| |
| 100%
| lsar
| MacBinary
| default
|
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| id metadata |
|---|
| key | value |
|---|
| macFileType | [ONLN] |
| macFileCreator | [HLX2] |
hex view+--------+-------------------------+-------------------------+--------+--------+
|00000000| 00 1b 48 57 32 33 20 46 | 50 55 20 4f 70 65 72 61 |..HW23 F|PU Opera|
|00000010| 74 69 6f 6e 73 20 6f 6e | 20 51 75 61 64 00 00 00 |tions on| Quad...|
|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 4f 4e 4c 4e 48 4c 58 | 32 01 00 00 00 00 00 00 |.ONLNHLX|2.......|
|00000050| 00 00 00 00 01 ad 2e 00 | 00 0d 1a aa b7 1e 78 aa |........|......x.|
|00000060| ca ba 29 00 00 00 00 00 | 00 00 00 00 00 00 00 00 |..).....|........|
|00000070| 00 00 00 00 00 00 00 00 | 00 00 81 81 8a 8b 00 00 |........|........|
|00000080| 48 57 20 32 33 20 2d 20 | 46 50 55 20 4f 70 65 72 |HW 23 - |FPU Oper|
|00000090| 61 74 69 6f 6e 73 20 6f | 6e 20 4d 61 63 69 6e 74 |ations o|n Macint|
|000000a0| 6f 73 68 20 51 75 61 64 | 72 61 20 43 6f 6d 70 75 |osh Quad|ra Compu|
|000000b0| 74 65 72 73 0d 48 61 72 | 64 77 61 72 65 09 0d 52 |ters.Har|dware..R|
|000000c0| 65 76 69 73 65 64 20 62 | 79 3a 09 54 69 6d 20 44 |evised b|y:.Tim D|
|000000d0| 69 65 72 6b 73 09 53 65 | 70 74 65 6d 62 65 72 20 |ierks.Se|ptember |
|000000e0| 31 39 39 32 0d 57 72 69 | 74 74 65 6e 20 62 79 3a |1992.Wri|tten by:|
|000000f0| 09 4a 6f 6e 20 4f 6b 61 | 64 61 2c 20 53 41 4e 45 |.Jon Oka|da, SANE|
|00000100| 69 74 61 74 69 6f 6e 20 | 45 6e 67 69 6e 65 65 72 |itation |Engineer|
|00000110| 2c 20 44 54 45 09 4a 75 | 6e 65 20 31 39 39 32 0d |, DTE.Ju|ne 1992.|
|00000120| 54 68 69 73 20 54 65 63 | 68 6e 69 63 61 6c 20 4e |This Tec|hnical N|
|00000130| 6f 74 65 20 64 69 73 63 | 75 73 73 65 73 20 66 6c |ote disc|usses fl|
|00000140| 6f 61 74 69 6e 67 2d 70 | 6f 69 6e 74 20 75 6e 69 |oating-p|oint uni|
|00000150| 74 20 28 46 50 55 29 20 | 69 6e 73 74 72 75 63 74 |t (FPU) |instruct|
|00000160| 69 6f 6e 20 73 75 70 70 | 6f 72 74 20 6f 6e 20 4d |ion supp|ort on M|
|00000170| 61 63 69 6e 74 6f 73 68 | 20 51 75 61 64 72 61 20 |acintosh| Quadra |
|00000180| 70 6c 61 74 66 6f 72 6d | 73 20 77 69 74 68 20 73 |platform|s with s|
|00000190| 70 65 63 69 61 6c 20 65 | 6d 70 68 61 73 69 73 20 |pecial e|mphasis |
|000001a0| 67 69 76 65 6e 20 74 6f | 20 63 6f 6d 70 61 74 69 |given to| compati|
|000001b0| 62 69 6c 69 74 79 20 61 | 6e 64 20 70 65 72 66 6f |bility a|nd perfo|
|000001c0| 72 6d 61 6e 63 65 20 63 | 6f 6e 63 65 72 6e 73 2e |rmance c|oncerns.|
|000001d0| 0d 43 68 61 6e 67 65 73 | 20 73 69 6e 63 65 20 4a |.Changes| since J|
|000001e0| 75 6e 65 20 31 39 39 32 | 3a 20 41 64 64 65 64 20 |une 1992|: Added |
|000001f0| 77 61 72 6e 69 6e 67 20 | 74 6f 20 63 68 65 63 6b |warning |to check|
|00000200| 20 66 6f 72 20 61 6e 20 | 46 50 55 20 62 65 66 6f | for an |FPU befo|
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|00000220| 20 65 78 65 63 75 74 65 | 20 46 50 55 20 69 6e 73 | execute| FPU ins|
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|00000240| 64 75 63 74 69 6f 6e 0d | 54 68 65 20 4d 61 63 69 |duction.|The Maci|
|00000250| 6e 74 6f 73 68 20 51 75 | 61 64 72 61 20 63 6f 6d |ntosh Qu|adra com|
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|00000270| 69 72 73 74 20 41 70 70 | 6c 65 20 70 72 6f 64 75 |irst App|le produ|
|00000280| 63 74 73 20 74 6f 20 75 | 73 65 20 74 68 65 20 4d |cts to u|se the M|
|00000290| 6f 74 6f 72 6f 6c 61 20 | 36 38 30 34 30 20 6d 69 |otorola |68040 mi|
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|00000300| 20 70 65 72 66 6f 72 6d | 20 62 61 73 69 63 20 66 | perform| basic f|
|00000310| 6c 6f 61 74 69 6e 67 2d | 70 6f 69 6e 74 20 6f 70 |loating-|point op|
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|00000360| 43 36 38 38 38 31 2f 32 | 20 66 6c 6f 61 74 69 6e |C68881/2| floatin|
|00000370| 67 2d 70 6f 69 6e 74 20 | 63 6f 70 72 6f 63 65 73 |g-point |coproces|
|00000380| 73 6f 72 20 77 6f 72 6b | 69 6e 67 20 69 6e 20 63 |sor work|ing in c|
|00000390| 6f 6e 6a 75 6e 63 74 69 | 6f 6e 20 77 69 74 68 20 |onjuncti|on with |
|000003a0| 61 6e 20 4d 43 36 38 30 | 32 30 2f 30 33 30 20 6d |an MC680|20/030 m|
|000003b0| 69 63 72 6f 70 72 6f 63 | 65 73 73 6f 72 2e 20 54 |icroproc|essor. T|
|000003c0| 68 69 73 20 4e 6f 74 65 | 20 61 64 64 72 65 73 73 |his Note| address|
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|000003e0| 20 61 6e 64 20 70 65 72 | 66 6f 72 6d 61 6e 63 65 | and per|formance|
|000003f0| 20 69 73 73 75 65 73 20 | 66 6f 72 20 51 75 61 64 | issues |for Quad|
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|00000410| 63 75 74 69 6e 67 20 46 | 50 55 20 69 6e 73 74 72 |cuting F|PU instr|
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|00000440| 69 74 6c 79 20 69 6e 20 | 61 73 73 65 6d 62 6c 79 |itly in |assembly|
|00000450| 20 6c 61 6e 67 75 61 67 | 65 20 6f 72 20 67 65 6e | languag|e or gen|
|00000460| 65 72 61 74 65 64 20 62 | 79 20 63 6f 6d 70 69 6c |erated b|y compil|
|00000470| 65 72 73 20 28 2d 6d 63 | 36 38 38 38 31 20 61 6e |ers (-mc|68881 an|
|00000480| 64 20 2d 65 6c 65 6d 73 | 38 38 31 20 6d 6f 64 65 |d -elems|881 mode|
|00000490| 73 20 66 6f 72 20 4d 50 | 57 20 63 6f 6d 70 69 6c |s for MP|W compil|
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|000004b0| 63 75 72 72 65 6e 74 6c | 79 20 61 76 61 69 6c 61 |currentl|y availa|
|000004c0| 62 6c 65 20 36 38 30 34 | 30 20 70 72 6f 63 65 73 |ble 6804|0 proces|
|000004d0| 73 6f 72 73 20 68 61 76 | 65 20 61 6e 20 6f 6e 62 |sors hav|e an onb|
|000004e0| 6f 61 72 64 20 46 50 55 | 2c 20 69 74 20 69 73 20 |oard FPU|, it is |
|000004f0| 69 6d 70 6f 72 74 61 6e | 74 20 74 6f 20 75 73 65 |importan|t to use|
|00000500| 20 47 65 73 74 61 6c 74 | 20 74 6f 20 76 65 72 69 | Gestalt| to veri|
|00000510| 66 79 20 74 68 65 20 65 | 78 69 73 74 65 6e 63 65 |fy the e|xistence|
|00000520| 20 6f 66 20 61 20 66 6c | 6f 61 74 69 6e 67 2d 70 | of a fl|oating-p|
|00000530| 6f 69 6e 74 20 63 6f 70 | 72 6f 63 65 73 73 6f 72 |oint cop|rocessor|
|00000540| 20 62 65 66 6f 72 65 20 | 61 74 74 65 6d 70 74 69 | before |attempti|
|00000550| 6e 67 20 74 6f 20 75 73 | 65 20 61 6e 79 20 46 50 |ng to us|e any FP|
|00000560| 55 20 69 6e 73 74 72 75 | 63 74 69 6f 6e 73 2e 20 |U instru|ctions. |
|00000570| 4d 6f 74 6f 72 6f 6c 61 | 20 68 61 73 20 61 6e 6e |Motorola| has ann|
|00000580| 6f 75 6e 63 65 64 20 61 | 20 76 61 72 69 61 6e 74 |ounced a| variant|
|00000590| 20 6f 66 20 74 68 65 20 | 36 38 30 34 30 20 77 69 | of the |68040 wi|
|000005a0| 74 68 6f 75 74 20 61 6e | 20 46 50 55 20 75 6e 69 |thout an| FPU uni|
|000005b0| 74 3b 20 74 68 69 73 20 | 63 68 69 70 20 68 61 73 |t; this |chip has|
|000005c0| 20 6d 6f 73 74 20 6f 66 | 20 74 68 65 20 63 61 63 | most of| the cac|
|000005d0| 68 69 6e 67 20 63 68 61 | 72 61 63 74 65 72 69 73 |hing cha|racteris|
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|00000600| 6f 65 73 20 6e 6f 74 20 | 73 75 70 70 6f 72 74 20 |oes not |support |
|00000610| 74 68 65 20 36 38 38 38 | 31 2f 32 20 6f 70 63 6f |the 6888|1/2 opco|
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|00000640| 69 72 63 75 69 74 72 79 | 20 69 6e 20 74 68 65 20 |ircuitry| in the |
|00000650| 36 38 30 34 30 20 64 6f | 65 73 20 6e 6f 74 20 62 |68040 do|es not b|
|00000660| 79 20 69 74 73 65 6c 66 | 20 73 75 70 70 6f 72 74 |y itself| support|
|00000670| 20 74 68 65 20 66 75 6c | 6c 20 66 75 6e 63 74 69 | the ful|l functi|
|00000680| 6f 6e 61 6c 69 74 79 20 | 6f 66 20 74 68 65 20 4d |onality |of the M|
|00000690| 43 36 38 38 38 31 2f 32 | 2e 20 4d 6f 74 6f 72 6f |C68881/2|. Motoro|
|000006a0| 6c 61 20 68 61 73 20 70 | 72 6f 76 69 64 65 64 20 |la has p|rovided |
|000006b0| 61 20 66 6c 6f 61 74 69 | 6e 67 2d 70 6f 69 6e 74 |a floati|ng-point|
|000006c0| 20 73 6f 66 74 77 61 72 | 65 20 70 61 63 6b 61 67 | softwar|e packag|
|000006d0| 65 20 28 46 50 53 50 29 | 20 77 68 69 63 68 20 65 |e (FPSP)| which e|
|000006e0| 6d 75 6c 61 74 65 73 20 | 61 6c 6c 20 6f 66 20 74 |mulates |all of t|
|000006f0| 68 65 20 4d 43 36 38 38 | 38 31 2f 32 20 66 75 6e |he MC688|81/2 fun|
|00000700| 63 74 69 6f 6e 61 6c 69 | 74 79 20 74 68 61 74 20 |ctionali|ty that |
|00000710| 69 73 20 6e 6f 74 20 70 | 72 6f 76 69 64 65 64 20 |is not p|rovided |
|00000720| 62 79 20 74 68 65 20 36 | 38 30 34 30 2e 20 54 68 |by the 6|8040. Th|
|00000730| 69 73 20 70 61 63 6b 61 | 67 65 20 72 65 73 69 64 |is packa|ge resid|
|00000740| 65 73 20 69 6e 20 74 68 | 65 20 6f 70 65 72 61 74 |es in th|e operat|
|00000750| 69 6e 67 20 73 79 73 74 | 65 6d 20 6f 66 20 74 68 |ing syst|em of th|
|00000760| 65 20 51 75 61 64 72 61 | 2e 20 57 68 65 6e 20 74 |e Quadra|. When t|
|00000770| 68 65 20 36 38 30 34 30 | 20 72 65 71 75 69 72 65 |he 68040| require|
|00000780| 73 20 65 6d 75 6c 61 74 | 69 6f 6e 20 73 65 72 76 |s emulat|ion serv|
|00000790| 69 63 65 73 20 69 6e 20 | 74 68 65 20 63 6f 75 72 |ices in |the cour|
|000007a0| 73 65 20 6f 66 20 65 78 | 65 63 75 74 69 6e 67 20 |se of ex|ecuting |
|000007b0| 61 6e 20 46 50 55 20 69 | 6e 73 74 72 75 63 74 69 |an FPU i|nstructi|
|000007c0| 6f 6e 2c 20 69 74 20 74 | 72 61 70 73 20 74 6f 20 |on, it t|raps to |
|000007d0| 74 68 65 20 46 50 53 50 | 20 76 69 61 20 6f 6e 65 |the FPSP| via one|
|000007e0| 20 6f 66 20 73 65 76 65 | 72 61 6c 20 65 78 63 65 | of seve|ral exce|
|000007f0| 70 74 69 6f 6e 20 76 65 | 63 74 6f 72 73 2c 20 64 |ption ve|ctors, d|
|00000800| 65 70 65 6e 64 69 6e 67 | 20 6f 6e 20 74 68 65 20 |epending| on the |
|00000810| 74 79 70 65 20 6f 66 20 | 65 6d 75 6c 61 74 69 6f |type of |emulatio|
|00000820| 6e 20 74 68 61 74 20 69 | 73 20 6e 65 65 64 65 64 |n that i|s needed|
|00000830| 2e 20 54 68 65 20 63 6f | 6d 62 69 6e 61 74 69 6f |. The co|mbinatio|
|00000840| 6e 20 6f 66 20 74 68 65 | 20 36 38 30 34 30 20 61 |n of the| 68040 a|
|00000850| 6e 64 20 46 50 53 50 20 | 65 6e 61 62 6c 65 73 20 |nd FPSP |enables |
|00000860| 51 75 61 64 72 61 20 63 | 6f 6d 70 75 74 65 72 73 |Quadra c|omputers|
|00000870| 20 74 6f 20 72 75 6e 20 | 6f 6c 64 20 75 73 65 72 | to run |old user|
|00000880| 20 63 6f 64 65 20 77 69 | 74 68 6f 75 74 20 6d 6f | code wi|thout mo|
|00000890| 64 69 66 69 63 61 74 69 | 6f 6e 20 75 6e 6c 65 73 |dificati|on unles|
|000008a0| 73 20 74 68 65 20 63 6f | 64 65 20 75 73 65 73 20 |s the co|de uses |
|000008b0| 66 6c 6f 61 74 69 6e 67 | 2d 70 6f 69 6e 74 20 65 |floating|-point e|
|000008c0| 78 63 65 70 74 69 6f 6e | 20 68 61 6e 64 6c 65 72 |xception| handler|
|000008d0| 73 2e 20 0d 49 66 20 75 | 73 65 72 20 63 6f 64 65 |s. .If u|ser code|
|000008e0| 20 69 6e 63 6c 75 64 65 | 73 20 66 6c 6f 61 74 69 | include|s floati|
|000008f0| 6e 67 2d 70 6f 69 6e 74 | 20 65 78 63 65 70 74 69 |ng-point| excepti|
|00000900| 6f 6e 20 68 61 6e 64 6c | 65 72 73 2c 20 74 68 65 |on handl|ers, the|
|00000910| 20 68 61 6e 64 6c 65 72 | 73 20 6d 75 73 74 20 62 | handler|s must b|
|00000920| 65 20 6d 6f 64 69 66 69 | 65 64 20 74 6f 20 72 65 |e modifi|ed to re|
|00000930| 66 6c 65 63 74 20 74 68 | 65 20 46 53 41 56 45 20 |flect th|e FSAVE |
|00000940| 73 74 61 74 65 20 66 72 | 61 6d 65 73 20 6f 66 20 |state fr|ames of |
|00000950| 74 68 65 20 36 38 30 34 | 30 2c 20 77 68 69 63 68 |the 6804|0, which|
|00000960| 20 64 69 66 66 65 72 20 | 66 72 6f 6d 20 74 68 6f | differ |from tho|
|00000970| 73 65 20 6f 66 20 74 68 | 65 20 4d 43 36 38 38 38 |se of th|e MC6888|
|00000980| 31 2f 32 2e 20 49 6e 20 | 61 64 64 69 74 69 6f 6e |1/2. In |addition|
|00000990| 2c 20 76 65 63 74 6f 72 | 69 6e 67 20 74 6f 20 73 |, vector|ing to s|
|000009a0| 75 63 68 20 68 61 6e 64 | 6c 65 72 73 20 66 6f 72 |uch hand|lers for|
|000009b0| 20 74 68 65 20 36 38 30 | 34 30 20 6d 75 73 74 20 | the 680|40 must |
|000009c0| 62 65 20 64 6f 6e 65 20 | 77 69 74 68 20 63 61 72 |be done |with car|
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|000009e0| 65 6e 74 72 79 20 74 6f | 20 74 68 65 20 46 50 53 |entry to| the FPS|
|000009f0| 50 20 6e 6f 74 20 62 65 | 20 63 6f 6d 70 72 6f 6d |P not be| comprom|
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|00000a10| 68 65 20 36 38 30 34 30 | 20 69 6e 20 61 20 51 75 |he 68040| in a Qu|
|00000a20| 61 64 72 61 20 69 6e 76 | 6f 6b 65 73 20 74 68 65 |adra inv|okes the|
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|00000a50| 6c 6c 20 73 75 66 66 65 | 72 20 72 65 6c 61 74 69 |ll suffe|r relati|
|00000a60| 76 65 20 74 6f 20 61 6e | 20 4d 43 36 38 38 38 31 |ve to an| MC68881|
|00000a70| 2f 32 20 70 6c 61 74 66 | 6f 72 6d 20 62 65 63 61 |/2 platf|orm beca|
|00000a80| 75 73 65 20 74 68 65 20 | 73 6f 66 74 77 61 72 65 |use the |software|
|00000a90| 20 65 6d 75 6c 61 74 69 | 6f 6e 20 6f 66 20 63 6f | emulati|on of co|
|00000aa0| 6d 70 6c 65 78 20 61 6c | 67 6f 72 69 74 68 6d 73 |mplex al|gorithms|
|00000ab0| 20 69 6e 76 6f 6c 76 69 | 6e 67 20 66 6c 6f 61 74 | involvi|ng float|
|00000ac0| 69 6e 67 2d 70 6f 69 6e | 74 20 63 61 6c 63 75 6c |ing-poin|t calcul|
|00000ad0| 61 74 69 6f 6e 73 20 61 | 6e 64 20 65 78 63 65 70 |ations a|nd excep|
|00000ae0| 74 69 6f 6e 20 73 74 61 | 74 65 20 73 69 6d 70 6c |tion sta|te simpl|
|00000af0| 79 20 63 61 6e 6e 6f 74 | 20 6f 75 74 70 65 72 66 |y cannot| outperf|
|00000b00| 6f 72 6d 20 64 65 64 69 | 63 61 74 65 64 20 68 61 |orm dedi|cated ha|
|00000b10| 72 64 77 61 72 65 20 61 | 6e 64 20 6d 69 63 72 6f |rdware a|nd micro|
|00000b20| 63 6f 64 65 2e 20 49 6e | 20 61 64 64 69 74 69 6f |code. In| additio|
|00000b30| 6e 2c 20 74 68 65 20 69 | 6e 73 74 72 75 63 74 69 |n, the i|nstructi|
|00000b40| 6f 6e 20 63 61 63 68 65 | 20 6d 75 73 74 20 63 6f |on cache| must co|
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|00000b60| 74 72 75 63 74 69 6f 6e | 73 20 6f 66 20 65 6d 75 |truction|s of emu|
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|00000b80| 63 63 6f 6d 70 6c 69 73 | 68 20 77 68 61 74 20 74 |ccomplis|h what t|
|00000b90| 68 65 20 4d 43 36 38 38 | 38 31 2f 32 20 64 6f 65 |he MC688|81/2 doe|
|00000ba0| 73 20 69 6e 20 61 20 73 | 69 6e 67 6c 65 20 46 50 |s in a s|ingle FP|
|00000bb0| 55 20 69 6e 73 74 72 75 | 63 74 69 6f 6e 2e 20 46 |U instru|ction. F|
|00000bc0| 69 6e 61 6c 6c 79 2c 20 | 46 50 53 50 20 69 6e 74 |inally, |FPSP int|
|00000bd0| 65 72 76 65 6e 74 69 6f | 6e 20 66 6c 75 73 68 65 |erventio|n flushe|
|00000be0| 73 20 74 68 65 20 46 50 | 55 20 70 69 70 65 6c 69 |s the FP|U pipeli|
|00000bf0| 6e 65 2c 20 74 68 75 73 | 20 6e 65 67 61 74 69 6e |ne, thus| negatin|
|00000c00| 67 20 61 6e 79 20 70 65 | 72 66 6f 72 6d 61 6e 63 |g any pe|rformanc|
|00000c10| 65 20 65 6e 68 61 6e 63 | 65 6d 65 6e 74 73 20 61 |e enhanc|ements a|
|00000c20| 63 68 69 65 76 61 62 6c | 65 20 74 68 72 6f 75 67 |chievabl|e throug|
|00000c30| 68 20 6f 76 65 72 6c 61 | 70 70 69 6e 67 20 65 78 |h overla|pping ex|
|00000c40| 65 63 75 74 69 6f 6e 20 | 6f 66 20 46 50 55 20 69 |ecution |of FPU i|
|00000c50| 6e 73 74 72 75 63 74 69 | 6f 6e 73 2e 0d 46 50 55 |nstructi|ons..FPU|
|00000c60| 20 49 6e 73 74 72 75 63 | 74 69 6f 6e 73 20 50 72 | Instruc|tions Pr|
|00000c70| 6f 76 69 64 65 64 20 62 | 79 20 74 68 65 20 36 38 |ovided b|y the 68|
|00000c80| 30 34 30 0d 54 68 65 20 | 66 6f 6c 6c 6f 77 69 6e |040.The |followin|
|00000c90| 67 20 46 50 55 20 69 6e | 73 74 72 75 63 74 69 6f |g FPU in|structio|
|00000ca0| 6e 73 20 61 72 65 20 73 | 75 70 70 6f 72 74 65 64 |ns are s|upported|
|00000cb0| 20 62 79 20 74 68 65 20 | 36 38 30 34 30 3a 0d 09 | by the |68040:..|
|00000cc0| 09 46 41 42 53 09 09 09 | 41 62 73 6f 6c 75 74 65 |.FABS...|Absolute|
|00000cd0| 20 76 61 6c 75 65 0d 09 | 09 46 44 41 42 53 2a 09 | value..|.FDABS*.|
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|00000cf0| 72 6f 75 6e 64 65 64 20 | 74 6f 20 64 6f 75 62 6c |rounded |to doubl|
|00000d00| 65 20 70 72 65 63 69 73 | 69 6f 6e 0d 09 09 46 53 |e precis|ion...FS|
|00000d10| 41 42 53 2a 09 09 41 62 | 73 6f 6c 75 74 65 20 76 |ABS*..Ab|solute v|
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|00000d30| 73 69 6e 67 6c 65 20 70 | 72 65 63 69 73 69 6f 6e |single p|recision|
|00000d40| 0d 09 09 46 41 44 44 09 | 09 09 41 64 64 69 74 69 |...FADD.|..Additi|
|00000d50| 6f 6e 0d 09 09 46 44 41 | 44 44 2a 09 09 41 64 64 |on...FDA|DD*..Add|
|00000d60| 69 74 69 6f 6e 20 72 6f | 75 6e 64 65 64 20 74 6f |ition ro|unded to|
|00000d70| 20 64 6f 75 62 6c 65 20 | 70 72 65 63 69 73 69 6f | double |precisio|
|00000d80| 6e 0d 09 09 46 53 41 44 | 44 2a 09 09 41 64 64 69 |n...FSAD|D*..Addi|
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|000053a0| 69 6e 69 6d 61 6c 20 42 | 53 55 4e 20 68 61 6e 64 |inimal B|SUN hand|
|000053b0| 6c 65 72 20 77 6f 75 6c | 64 20 72 65 71 75 69 72 |ler woul|d requir|
|000053c0| 65 20 61 64 64 69 74 69 | 6f 6e 61 6c 20 69 6e 74 |e additi|onal int|
|000053d0| 65 72 76 65 6e 74 69 6f | 6e 20 28 76 69 61 20 6f |erventio|n (via o|
|000053e0| 6e 65 20 6f 66 20 66 6f | 75 72 20 6d 65 74 68 6f |ne of fo|ur metho|
|000053f0| 64 73 20 6f 75 74 6c 69 | 6e 65 64 20 69 6e 20 74 |ds outli|ned in t|
|00005400| 68 65 20 75 73 65 72 20 | 6d 61 6e 75 61 6c 73 20 |he user |manuals |
|00005410| 66 6f 72 20 74 68 65 20 | 36 38 30 34 30 20 61 6e |for the |68040 an|
|00005420| 64 20 74 68 65 20 4d 43 | 36 38 38 38 31 2f 32 29 |d the MC|68881/2)|
|00005430| 20 74 6f 20 70 72 65 76 | 65 6e 74 20 69 6e 66 69 | to prev|ent infi|
|00005440| 6e 69 74 65 20 6c 6f 6f | 70 69 6e 67 20 6f 6e 20 |nite loo|ping on |
|00005450| 74 68 65 20 42 53 55 4e | 20 74 72 61 70 2e 0d 3b |the BSUN| trap..;|
|00005460| 20 2a 2a 2a 2a 2a 2a 2a | 2a 2a 2a 2a 2a 2a 2a 2a | *******|********|
|00005470| 2a 2a 2a 2a 2a 2a 2a 2a | 2a 2a 2a 2a 2a 2a 2a 2a |********|********|
|00005480| 2a 2a 2a 2a 2a 2a 2a 2a | 2a 2a 2a 2a 2a 2a 2a 2a |********|********|
|00005490| 2a 2a 2a 2a 2a 2a 2a 2a | 2a 2a 2a 2a 2a 2a 2a 2a |********|********|
|000054a0| 2a 2a 2a 2a 2a 2a 2a 2a | 2a 0d 3b 20 4d 69 6e 69 |********|*.; Mini|
|000054b0| 6d 75 6d 20 75 73 65 72 | 20 68 61 6e 64 6c 65 72 |mum user| handler|
|000054c0| 20 66 6f 72 20 65 6e 61 | 62 6c 65 64 20 49 4e 45 | for ena|bled INE|
|000054d0| 58 2c 20 44 5a 2c 20 55 | 4e 46 4c 2c 20 4f 50 45 |X, DZ, U|NFL, OPE|
|000054e0| 52 52 2c 20 4f 56 46 4c | 2c 0d 3b 20 6f 72 20 53 |RR, OVFL|,.; or S|
|000054f0| 4e 41 4e 20 66 6c 6f 61 | 74 69 6e 67 2d 70 6f 69 |NAN floa|ting-poi|
|00005500| 6e 74 20 65 78 63 65 70 | 74 69 6f 6e 20 6f 6e 20 |nt excep|tion on |
|00005510| 65 69 74 68 65 72 20 4d | 43 36 38 38 38 31 2f 32 |either M|C68881/2|
|00005520| 20 6f 72 20 0d 3b 20 4d | 61 63 69 6e 74 6f 73 68 | or .; M|acintosh|
|00005530| 20 51 75 61 64 72 61 20 | 70 6c 61 74 66 6f 72 6d | Quadra |platform|
|00005540| 73 2e 20 0d 3b 0d 3b 20 | 4e 4f 54 45 3a 20 20 46 |s. .;.; |NOTE: F|
|00005550| 6f 72 20 65 6e 61 62 6c | 65 64 20 44 5a 2c 20 4f |or enabl|ed DZ, O|
|00005560| 50 45 52 52 2c 20 61 6e | 64 20 53 4e 41 4e 20 65 |PERR, an|d SNAN e|
|00005570| 78 63 65 70 74 69 6f 6e | 73 20 66 6f 72 20 69 6e |xception|s for in|
|00005580| 73 74 72 75 63 74 69 6f | 6e 73 0d 3b 20 20 20 20 |structio|ns.; |
|00005590| 20 20 20 20 77 69 74 68 | 20 46 50 20 72 65 67 69 | with| FP regi|
|000055a0| 73 74 65 72 20 64 65 73 | 74 69 6e 61 74 69 6f 6e |ster des|tination|
|000055b0| 73 2c 20 6e 6f 20 72 65 | 73 75 6c 74 20 69 73 20 |s, no re|sult is |
|000055c0| 64 65 6c 69 76 65 72 65 | 64 20 61 74 20 61 6c 6c |delivere|d at all|
|000055d0| 20 74 6f 20 74 68 65 0d | 3b 20 20 20 20 20 20 20 | to the.|; |
|000055e0| 20 64 65 73 74 69 6e 61 | 74 69 6f 6e 20 72 65 67 | destina|tion reg|
|000055f0| 69 73 74 65 72 2e 0d 3b | 20 2a 2a 2a 2a 2a 2a 2a |ister..;| *******|
|00005600| 2a 2a 2a 2a 2a 2a 2a 2a | 2a 2a 2a 2a 2a 2a 2a 2a |********|********|
|00005610| 2a 2a 2a 2a 2a 2a 2a 2a | 2a 2a 2a 2a 2a 2a 2a 2a |********|********|
|00005620| 2a 2a 2a 2a 2a 2a 2a 2a | 2a 2a 2a 2a 2a 2a 2a 2a |********|********|
|00005630| 2a 2a 2a 2a 2a 2a 2a 2a | 2a 2a 2a 2a 2a 2a 2a 2a |********|********|
|00005640| 2a 0d 48 41 4e 44 4c 45 | 52 3a 0d 09 09 46 53 41 |*.HANDLE|R:...FSA|
|00005650| 56 45 09 09 2d 28 53 50 | 29 09 09 3b 20 73 61 76 |VE..-(SP|)..; sav|
|00005660| 65 20 69 6e 74 65 72 6e | 61 6c 20 46 50 55 20 73 |e intern|al FPU s|
|00005670| 74 61 74 65 0d 09 09 4d | 4f 56 45 2e 4c 09 09 44 |tate...M|OVE.L..D|
|00005680| 30 2c 2d 28 53 50 29 09 | 3b 20 73 61 76 65 20 44 |0,-(SP).|; save D|
|00005690| 30 2c 20 53 54 41 43 4b | 3a 20 20 44 30 20 73 61 |0, STACK|: D0 sa|
|000056a0| 76 65 20 3c 20 46 53 41 | 56 45 20 66 72 61 6d 65 |ve < FSA|VE frame|
|000056b0| 0d 09 09 4d 4f 56 45 51 | 09 09 23 30 2c 44 30 09 |...MOVEQ|..#0,D0.|
|000056c0| 09 3b 20 7a 65 72 6f 20 | 44 30 0d 09 09 4d 4f 56 |.; zero |D0...MOV|
|000056d0| 45 2e 42 09 09 34 28 53 | 50 29 2c 44 30 09 3b 20 |E.B..4(S|P),D0.; |
|000056e0| 4e 55 4c 4c 20 66 72 61 | 6d 65 3f 0d 09 09 42 45 |NULL fra|me?...BE|
|000056f0| 51 2e 42 09 09 40 4e 55 | 4c 4c 09 09 3b 20 79 65 |Q.B..@NU|LL..; ye|
|00005700| 73 2c 20 72 65 73 74 6f | 72 65 20 44 30 20 61 6e |s, resto|re D0 an|
|00005710| 64 20 46 50 55 20 73 74 | 61 74 65 0d 09 09 43 4d |d FPU st|ate...CM|
|00005720| 50 49 2e 42 09 09 23 24 | 34 31 2c 44 30 09 3b 20 |PI.B..#$|41,D0.; |
|00005730| 51 75 61 64 72 61 20 28 | 36 38 30 34 30 29 20 49 |Quadra (|68040) I|
|00005740| 44 3f 0d 09 09 42 4e 45 | 2e 42 09 09 40 43 4f 50 |D?...BNE|.B..@COP|
|00005750| 52 4f 43 09 3b 20 6e 6f | 2c 20 61 73 73 75 6d 65 |ROC.; no|, assume|
|00005760| 20 4d 43 36 38 38 38 31 | 2f 32 0d 3b 20 51 75 61 | MC68881|/2.; Qua|
|00005770| 64 72 61 20 46 53 41 56 | 45 20 66 72 61 6d 65 0d |dra FSAV|E frame.|
|00005780| 09 09 4d 4f 56 45 2e 42 | 09 09 35 28 53 50 29 2c |..MOVE.B|..5(SP),|
|00005790| 44 30 09 3b 20 44 30 20 | 3c 2d 20 66 72 61 6d 65 |D0.; D0 |<- frame|
|000057a0| 20 73 69 7a 65 0d 09 09 | 42 45 51 2e 42 09 09 40 | size...|BEQ.B..@|
|000057b0| 4e 55 4c 4c 09 09 3b 20 | 72 65 73 74 6f 72 65 20 |NULL..; |restore |
|000057c0| 73 74 61 74 65 20 69 66 | 20 36 38 30 34 30 20 49 |state if| 68040 I|
|000057d0| 44 4c 45 20 66 72 61 6d | 65 0d 3b 20 51 75 61 64 |DLE fram|e.; Quad|
|000057e0| 72 61 20 55 4e 49 4d 50 | 4c 45 4d 45 4e 54 45 44 |ra UNIMP|LEMENTED|
|000057f0| 20 49 4e 53 54 52 55 43 | 54 49 4f 4e 20 6f 72 20 | INSTRUC|TION or |
|00005800| 42 55 53 59 20 46 53 41 | 56 45 20 66 72 61 6d 65 |BUSY FSA|VE frame|
|00005810| 0d 09 09 53 55 42 49 2e | 42 09 09 23 32 30 2c 44 |...SUBI.|B..#20,D|
|00005820| 30 09 09 3b 20 44 30 20 | 3c 2d 20 6f 66 66 73 65 |0..; D0 |<- offse|
|00005830| 74 20 6f 66 20 45 31 2f | 45 33 20 62 79 74 65 20 |t of E1/|E3 byte |
|00005840| 66 72 6f 6d 20 28 53 50 | 29 0d 09 09 42 43 4c 52 |from (SP|)...BCLR|
|00005850| 2e 42 09 09 23 31 2c 28 | 53 50 2c 44 30 29 09 3b |.B..#1,(|SP,D0).;|
|00005860| 20 74 65 73 74 20 61 6e | 64 20 63 6c 65 61 72 20 | test an|d clear |
|00005870| 45 33 20 62 79 74 65 0d | 09 09 42 4e 45 2e 42 09 |E3 byte.|..BNE.B.|
|00005880| 09 40 4e 55 4c 4c 09 09 | 3b 20 72 65 73 74 6f 72 |.@NULL..|; restor|
|00005890| 65 20 73 74 61 74 65 20 | 69 66 20 45 33 20 77 61 |e state |if E3 wa|
|000058a0| 73 20 73 65 74 0d 09 09 | 42 43 4c 52 2e 42 09 09 |s set...|BCLR.B..|
|000058b0| 23 32 2c 28 53 50 2c 44 | 30 29 09 3b 20 45 31 20 |#2,(SP,D|0).; E1 |
|000058c0| 65 78 63 65 70 74 69 6f | 6e 2c 20 63 6c 65 61 72 |exceptio|n, clear|
|000058d0| 20 45 31 20 62 79 74 65 | 0d 3b 20 52 65 73 74 6f | E1 byte|.; Resto|
|000058e0| 72 65 20 73 74 61 74 65 | 20 61 6e 64 20 72 65 73 |re state| and res|
|000058f0| 75 6d 65 20 65 78 65 63 | 75 74 69 6f 6e 0d 40 4e |ume exec|ution.@N|
|00005900| 55 4c 4c 3a 09 4d 4f 56 | 45 2e 4c 09 09 28 53 50 |ULL:.MOV|E.L..(SP|
|00005910| 29 2b 2c 44 30 09 3b 20 | 72 65 73 74 6f 72 65 20 |)+,D0.; |restore |
|00005920| 44 30 2c 20 53 54 41 43 | 4b 3a 20 20 46 53 41 56 |D0, STAC|K: FSAV|
|00005930| 45 20 66 72 61 6d 65 0d | 09 09 46 52 45 53 54 4f |E frame.|..FRESTO|
|00005940| 52 45 09 28 53 50 29 2b | 09 09 3b 20 72 65 73 74 |RE.(SP)+|..; rest|
|00005950| 6f 72 65 20 46 50 55 20 | 73 74 61 74 65 0d 09 09 |ore FPU |state...|
|00005960| 52 54 45 09 09 09 09 3b | 20 72 65 73 75 6d 65 20 |RTE....;| resume |
|00005970| 70 72 6f 63 65 73 73 69 | 6e 67 0d 3b 20 4d 43 36 |processi|ng.; MC6|
|00005980| 38 38 38 31 2f 32 20 49 | 44 4c 45 20 46 53 41 56 |8881/2 I|DLE FSAV|
|00005990| 45 20 66 72 61 6d 65 0d | 40 43 4f 50 52 4f 43 3a |E frame.|@COPROC:|
|000059a0| 09 4d 4f 56 45 2e 42 09 | 09 35 28 53 50 29 2c 44 |.MOVE.B.|.5(SP),D|
|000059b0| 30 09 3b 20 44 30 20 3c | 2d 20 49 44 4c 45 20 66 |0.; D0 <|- IDLE f|
|000059c0| 72 61 6d 65 20 73 69 7a | 65 0d 09 09 41 44 44 51 |rame siz|e...ADDQ|
|000059d0| 2e 42 09 09 23 34 2c 44 | 30 09 09 3b 20 63 6f 6d |.B..#4,D|0..; com|
|000059e0| 70 65 6e 73 61 74 65 20 | 66 6f 72 20 44 30 20 73 |pensate |for D0 s|
|000059f0| 61 76 65 20 76 61 6c 75 | 65 20 6f 6e 20 73 74 61 |ave valu|e on sta|
|00005a00| 63 6b 0d 09 09 42 53 45 | 54 2e 42 09 09 23 33 2c |ck...BSE|T.B..#3,|
|00005a10| 28 53 50 2c 44 30 29 09 | 3b 20 73 65 74 20 62 69 |(SP,D0).|; set bi|
|00005a20| 74 20 32 37 20 6f 66 20 | 42 49 55 0d 09 09 42 52 |t 27 of |BIU...BR|
|00005a30| 41 2e 42 09 09 40 4e 55 | 4c 4c 09 09 3b 20 72 65 |A.B..@NU|LL..; re|
|00005a40| 73 74 6f 72 65 20 73 74 | 61 74 65 0d 49 6e 73 74 |store st|ate.Inst|
|00005a50| 61 6c 6c 61 74 69 6f 6e | 20 6f 66 20 55 73 65 72 |allation| of User|
|00005a60| 20 46 6c 6f 61 74 69 6e | 67 2d 50 6f 69 6e 74 20 | Floatin|g-Point |
|00005a70| 45 78 63 65 70 74 69 6f | 6e 20 48 61 6e 64 6c 65 |Exceptio|n Handle|
|00005a80| 72 73 0d 43 75 72 72 65 | 6e 74 20 4d 50 57 20 6c |rs.Curre|nt MPW l|
|00005a90| 61 6e 67 75 61 67 65 20 | 6c 69 62 72 61 72 69 65 |anguage |librarie|
|00005aa0| 73 20 28 4d 50 57 20 32 | 2e 30 2e 32 20 6f 72 20 |s (MPW 2|.0.2 or |
|00005ab0| 6c 61 74 65 72 20 72 65 | 6c 65 61 73 65 73 20 61 |later re|leases a|
|00005ac0| 6e 64 20 4c 61 6e 67 75 | 61 67 65 20 53 79 73 74 |nd Langu|age Syst|
|00005ad0| 65 6d 73 20 46 4f 52 54 | 52 41 4e 20 76 65 72 73 |ems FORT|RAN vers|
|00005ae0| 69 6f 6e 20 33 2e 30 29 | 20 70 72 6f 76 69 64 65 |ion 3.0)| provide|
|00005af0| 20 66 6f 72 20 74 68 65 | 20 76 65 63 74 6f 72 69 | for the| vectori|
|00005b00| 6e 67 20 6f 66 20 75 73 | 65 72 20 66 6c 6f 61 74 |ng of us|er float|
|00005b10| 69 6e 67 2d 70 6f 69 6e | 74 20 65 78 63 65 70 74 |ing-poin|t except|
|00005b20| 69 6f 6e 20 68 61 6e 64 | 6c 65 72 73 20 69 6e 20 |ion hand|lers in |
|00005b30| 61 20 63 6f 6e 73 69 73 | 74 65 6e 74 20 61 6e 64 |a consis|tent and|
|00005b40| 20 70 6f 72 74 61 62 6c | 65 20 66 61 73 68 69 6f | portabl|e fashio|
|00005b50| 6e 20 66 6f 72 20 62 6f | 74 68 20 51 75 61 64 72 |n for bo|th Quadr|
|00005b60| 61 20 61 6e 64 20 4d 43 | 36 38 38 38 31 2f 32 20 |a and MC|68881/2 |
|00005b70| 4d 61 63 69 6e 74 6f 73 | 68 20 70 6c 61 74 66 6f |Macintos|h platfo|
|00005b80| 72 6d 73 2e 20 54 68 65 | 20 43 20 66 75 6e 63 74 |rms. The| C funct|
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|00005bb0| 63 74 6f 72 2c 20 74 68 | 65 20 50 61 73 63 61 6c |ctor, th|e Pascal|
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|00005bf0| 20 74 68 65 20 4c 61 6e | 67 75 61 67 65 20 53 79 | the Lan|guage Sy|
|00005c00| 73 74 65 6d 73 20 46 4f | 52 54 52 41 4e 20 73 75 |stems FO|RTRAN su|
|00005c10| 62 72 6f 75 74 69 6e 65 | 73 20 53 65 74 54 72 61 |broutine|s SetTra|
|00005c20| 70 56 65 63 74 6f 72 20 | 61 6e 64 20 47 65 74 54 |pVector |and GetT|
|00005c30| 72 61 70 56 65 63 74 6f | 72 20 61 6c 6c 6f 77 20 |rapVecto|r allow |
|00005c40| 75 73 65 72 73 20 74 6f | 20 69 6e 73 74 61 6c 6c |users to| install|
|00005c50| 20 61 6e 64 20 72 65 61 | 64 20 76 65 63 74 6f 72 | and rea|d vector|
|00005c60| 73 20 74 6f 20 74 68 65 | 69 72 20 66 6c 6f 61 74 |s to the|ir float|
|00005c70| 69 6e 67 2d 70 6f 69 6e | 74 20 65 78 63 65 70 74 |ing-poin|t except|
|00005c80| 69 6f 6e 20 68 61 6e 64 | 6c 65 72 73 20 76 69 61 |ion hand|lers via|
|00005c90| 20 74 68 65 20 75 73 65 | 20 6f 66 20 74 68 65 20 | the use| of the |
|00005ca0| 54 72 61 70 56 65 63 74 | 6f 72 20 73 74 72 75 63 |TrapVect|or struc|
|00005cb0| 74 75 72 65 2e 20 54 68 | 65 20 72 65 6c 65 76 61 |ture. Th|e releva|
|00005cc0| 6e 74 20 69 6e 74 65 72 | 66 61 63 65 20 66 69 6c |nt inter|face fil|
|00005cd0| 65 73 20 66 6f 72 20 74 | 68 65 73 65 20 6f 70 65 |es for t|hese ope|
|00005ce0| 72 61 74 69 6f 6e 73 20 | 61 72 65 20 7b 43 49 6e |rations |are {CIn|
|00005cf0| 63 6c 75 64 65 73 7d 53 | 41 4e 45 2e 68 2c 20 7b |cludes}S|ANE.h, {|
|00005d00| 50 49 6e 74 65 72 66 61 | 63 65 73 7d 53 41 4e 45 |PInterfa|ces}SANE|
|00005d10| 2e 70 2c 20 61 6e 64 20 | 7b 46 49 6e 63 6c 75 64 |.p, and |{FInclud|
|00005d20| 65 73 7d 53 41 4e 45 2e | 66 2e 20 0d 41 20 54 72 |es}SANE.|f. .A Tr|
|00005d30| 61 70 56 65 63 74 6f 72 | 20 73 74 72 75 63 74 75 |apVector| structu|
|00005d40| 72 65 20 69 73 20 63 6f | 6d 70 6f 73 65 64 20 6f |re is co|mposed o|
|00005d50| 66 20 73 65 76 65 6e 20 | 34 2d 62 79 74 65 20 66 |f seven |4-byte f|
|00005d60| 69 65 6c 64 73 20 74 68 | 61 74 20 72 65 70 72 65 |ields th|at repre|
|00005d70| 73 65 6e 74 20 74 68 65 | 20 65 6e 74 72 79 2d 70 |sent the| entry-p|
|00005d80| 6f 69 6e 74 20 61 64 64 | 72 65 73 73 65 73 20 6f |oint add|resses o|
|00005d90| 66 20 74 68 65 20 75 73 | 65 72 d5 73 20 42 53 55 |f the us|er.s BSU|
|00005da0| 4e 2c 20 49 4e 45 58 2c | 20 44 5a 2c 20 55 4e 46 |N, INEX,| DZ, UNF|
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|00005dd0| 6f 6e 20 68 61 6e 64 6c | 65 72 73 2c 20 72 65 73 |on handl|ers, res|
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|00005e10| 6e 74 20 66 6c 6f 61 74 | 69 6e 67 2d 70 6f 69 6e |nt float|ing-poin|
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|00005e40| 65 63 74 6f 72 20 73 74 | 72 75 63 74 75 72 65 2e |ector st|ructure.|
|00005e50| 20 49 6e 20 6f 72 64 65 | 72 20 74 6f 20 69 6e 73 | In orde|r to ins|
|00005e60| 74 61 6c 6c 20 74 68 65 | 69 72 20 6f 77 6e 20 65 |tall the|ir own e|
|00005e70| 78 63 65 70 74 69 6f 6e | 20 68 61 6e 64 6c 65 72 |xception| handler|
|00005e80| 73 2c 20 75 73 65 72 73 | 20 6d 75 73 74 20 66 69 |s, users| must fi|
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|00005eb0| 63 74 75 72 65 20 77 69 | 74 68 20 65 6e 74 72 79 |cture wi|th entry|
|00005ec0| 20 70 6f 69 6e 74 73 20 | 6f 66 20 74 68 65 69 72 | points |of their|
|00005ed0| 20 68 61 6e 64 6c 65 72 | 20 72 6f 75 74 69 6e 65 | handler| routine|
|00005ee0| 73 20 61 6e 64 20 74 68 | 65 6e 20 69 6e 76 6f 6b |s and th|en invok|
|00005ef0| 65 20 61 20 53 65 74 54 | 72 61 70 56 65 63 74 6f |e a SetT|rapVecto|
|00005f00| 72 20 72 6f 75 74 69 6e | 65 20 77 69 74 68 20 74 |r routin|e with t|
|00005f10| 68 61 74 20 73 74 72 75 | 63 74 75 72 65 20 61 73 |hat stru|cture as|
|00005f20| 20 74 68 65 20 6f 70 65 | 72 61 6e 64 2e 0d 47 65 | the ope|rand..Ge|
|00005f30| 74 54 72 61 70 56 65 63 | 74 6f 72 20 61 6e 64 20 |tTrapVec|tor and |
|00005f40| 53 65 74 54 72 61 70 56 | 65 63 74 6f 72 20 72 6f |SetTrapV|ector ro|
|00005f50| 75 74 69 6e 65 73 20 69 | 6e 76 6f 6c 76 65 20 70 |utines i|nvolve p|
|00005f60| 72 69 76 69 6c 65 67 65 | 64 20 6f 70 65 72 61 74 |rivilege|d operat|
|00005f70| 69 6f 6e 73 20 62 65 63 | 61 75 73 65 20 74 68 65 |ions bec|ause the|
|00005f80| 79 20 61 63 63 65 73 73 | 20 4d 6f 74 6f 72 6f 6c |y access| Motorol|
|00005f90| 61 20 6c 6f 77 2d 6d 65 | 6d 6f 72 79 20 76 65 63 |a low-me|mory vec|
|00005fa0| 74 6f 72 20 74 61 62 6c | 65 20 6c 6f 63 61 74 69 |tor tabl|e locati|
|00005fb0| 6f 6e 73 2e 20 46 6f 72 | 20 51 75 61 64 72 61 20 |ons. For| Quadra |
|00005fc0| 70 6c 61 74 66 6f 72 6d | 73 2c 20 74 68 65 20 73 |platform|s, the s|
|00005fd0| 69 74 75 61 74 69 6f 6e | 20 69 73 20 66 75 72 74 |ituation| is furt|
|00005fe0| 68 65 72 20 63 6f 6d 70 | 6c 69 63 61 74 65 64 20 |her comp|licated |
|00005ff0| 62 79 20 74 68 65 20 66 | 61 63 74 20 74 68 61 74 |by the f|act that|
|00006000| 20 66 69 76 65 20 6f 66 | 20 74 68 65 20 73 65 76 | five of| the sev|
|00006010| 65 6e 20 75 73 65 72 20 | 66 6c 6f 61 74 69 6e 67 |en user |floating|
|00006020| 2d 70 6f 69 6e 74 20 65 | 78 63 65 70 74 69 6f 6e |-point e|xception|
|00006030| 20 76 65 63 74 6f 72 73 | 20 61 72 65 20 73 74 6f | vectors| are sto|
|00006040| 72 65 64 20 62 79 20 74 | 68 65 20 73 79 73 74 65 |red by t|he syste|
|00006050| 6d 20 69 6e 20 73 65 63 | 6f 6e 64 61 72 79 20 6c |m in sec|ondary l|
|00006060| 6f 63 61 74 69 6f 6e 73 | 20 62 65 63 61 75 73 65 |ocations| because|
|00006070| 20 74 68 65 20 46 50 53 | 50 20 68 61 73 20 70 72 | the FPS|P has pr|
|00006080| 65 65 6d 70 74 65 64 20 | 74 68 65 20 6f 72 69 67 |eempted |the orig|
|00006090| 69 6e 61 6c 20 76 65 63 | 74 6f 72 20 74 61 62 6c |inal vec|tor tabl|
|000060a0| 65 20 6c 6f 63 61 74 69 | 6f 6e 73 2e 20 47 65 74 |e locati|ons. Get|
|000060b0| 54 72 61 70 56 65 63 74 | 6f 72 20 61 6e 64 20 53 |TrapVect|or and S|
|000060c0| 65 74 54 72 61 70 56 65 | 63 74 6f 72 20 69 6d 70 |etTrapVe|ctor imp|
|000060d0| 6c 65 6d 65 6e 74 61 74 | 69 6f 6e 73 20 63 69 72 |lementat|ions cir|
|000060e0| 63 75 6d 76 65 6e 74 20 | 74 68 65 73 65 20 64 69 |cumvent |these di|
|000060f0| 66 66 69 63 75 6c 74 69 | 65 73 20 62 79 20 63 61 |fficulti|es by ca|
|00006100| 6c 6c 69 6e 67 20 61 20 | 73 79 73 74 65 6d 20 75 |lling a |system u|
|00006110| 74 69 6c 69 74 79 2c 20 | 50 72 69 76 54 72 61 70 |tility, |PrivTrap|
|00006120| 2c 20 77 68 69 63 68 20 | 64 6f 65 73 20 61 6c 6c |, which |does all|
|00006130| 20 6f 66 20 74 68 65 20 | 77 6f 72 6b 20 6f 66 20 | of the |work of |
|00006140| 71 75 65 72 79 69 6e 67 | 20 6f 72 20 69 6e 73 74 |querying| or inst|
|00006150| 61 6c 6c 69 6e 67 20 74 | 68 65 20 75 73 65 72 d5 |alling t|he user.|
|00006160| 73 20 76 65 63 74 6f 72 | 73 2e 0d 54 68 65 20 50 |s vector|s..The P|
|00006170| 72 69 76 54 72 61 70 20 | 4d 65 63 68 61 6e 69 73 |rivTrap |Mechanis|
|00006180| 6d 0d 50 72 69 76 54 72 | 61 70 20 69 73 20 69 6d |m.PrivTr|ap is im|
|00006190| 70 6c 65 6d 65 6e 74 65 | 64 20 61 73 20 61 20 73 |plemente|d as a s|
|000061a0| 79 73 74 65 6d 20 74 72 | 61 70 2c 20 24 41 30 39 |ystem tr|ap, $A09|
|000061b0| 37 2e 20 55 70 6f 6e 20 | 65 6e 74 72 79 2c 20 69 |7. Upon |entry, i|
|000061c0| 74 20 65 78 70 65 63 74 | 73 20 61 20 73 65 6c 65 |t expect|s a sele|
|000061d0| 63 74 6f 72 20 76 61 6c | 75 65 20 69 6e 20 72 65 |ctor val|ue in re|
|000061e0| 67 69 73 74 65 72 20 44 | 30 2e 57 20 61 6e 64 20 |gister D|0.W and |
|000061f0| 61 20 54 72 61 70 56 65 | 63 74 6f 72 20 73 74 72 |a TrapVe|ctor str|
|00006200| 75 63 74 75 72 65 20 61 | 64 64 72 65 73 73 20 69 |ucture a|ddress i|
|00006210| 6e 20 61 64 64 72 65 73 | 73 20 72 65 67 69 73 74 |n addres|s regist|
|00006220| 65 72 20 41 30 2e 20 54 | 68 65 20 47 65 74 54 72 |er A0. T|he GetTr|
|00006230| 61 70 56 65 63 74 6f 72 | 20 6f 70 65 72 61 74 69 |apVector| operati|
|00006240| 6f 6e 20 72 65 71 75 69 | 72 65 73 20 61 20 73 65 |on requi|res a se|
|00006250| 6c 65 63 74 6f 72 20 76 | 61 6c 75 65 20 6f 66 20 |lector v|alue of |
|00006260| 31 3b 20 69 6e 20 74 68 | 69 73 20 63 61 73 65 2c |1; in th|is case,|
|00006270| 20 50 72 69 76 54 72 61 | 70 20 72 65 61 64 73 20 | PrivTra|p reads |
|00006280| 74 68 65 20 63 75 72 72 | 65 6e 74 20 66 6c 6f 61 |the curr|ent floa|
|00006290| 74 69 6e 67 2d 70 6f 69 | 6e 74 20 65 78 63 65 70 |ting-poi|nt excep|
|000062a0| 74 69 6f 6e 20 76 65 63 | 74 6f 72 73 20 69 6e 74 |tion vec|tors int|
|000062b0| 6f 20 74 68 65 20 54 72 | 61 70 56 65 63 74 6f 72 |o the Tr|apVector|
|000062c0| 20 73 74 72 75 63 74 75 | 72 65 20 61 74 20 28 41 | structu|re at (A|
|000062d0| 30 29 2e 20 54 68 65 20 | 73 65 6c 65 63 74 6f 72 |0). The |selector|
|000062e0| 20 76 61 6c 75 65 20 6f | 66 20 32 20 69 6e 76 6f | value o|f 2 invo|
|000062f0| 6b 65 73 20 74 68 65 20 | 53 65 74 54 72 61 70 56 |kes the |SetTrapV|
|00006300| 65 63 74 6f 72 20 6f 70 | 65 72 61 74 69 6f 6e 3b |ector op|eration;|
|00006310| 20 74 68 65 20 75 73 65 | 72 d5 73 20 65 78 63 65 | the use|r.s exce|
|00006320| 70 74 69 6f 6e 20 76 65 | 63 74 6f 72 73 20 69 6e |ption ve|ctors in|
|00006330| 20 74 68 65 20 54 72 61 | 70 56 65 63 74 6f 72 20 | the Tra|pVector |
|00006340| 73 74 72 75 63 74 75 72 | 65 20 61 74 20 28 41 30 |structur|e at (A0|
|00006350| 29 20 61 72 65 20 69 6e | 73 74 61 6c 6c 65 64 20 |) are in|stalled |
|00006360| 61 70 70 72 6f 70 72 69 | 61 74 65 6c 79 20 69 6e |appropri|ately in|
|00006370| 20 74 68 65 20 73 79 73 | 74 65 6d 2e 20 49 6e 20 | the sys|tem. In |
|00006380| 65 69 74 68 65 72 20 63 | 61 73 65 2c 20 72 65 67 |either c|ase, reg|
|00006390| 69 73 74 65 72 73 20 41 | 30 20 61 6e 64 20 41 31 |isters A|0 and A1|
|000063a0| 20 61 72 65 20 6d 6f 64 | 69 66 69 65 64 20 75 70 | are mod|ified up|
|000063b0| 6f 6e 20 65 78 69 74 2e | 0d 41 73 20 6f 66 20 74 |on exit.|.As of t|
|000063c0| 68 65 20 64 72 61 66 74 | 69 6e 67 20 6f 66 20 74 |he draft|ing of t|
|000063d0| 68 69 73 20 4e 6f 74 65 | 2c 20 6f 6e 6c 79 20 74 |his Note|, only t|
|000063e0| 68 65 20 51 75 61 64 72 | 61 20 61 6e 64 20 50 6f |he Quadr|a and Po|
|000063f0| 77 65 72 42 6f 6f 6b 20 | 31 37 30 20 70 6c 61 74 |werBook |170 plat|
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