Differences
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qdosmsq:fs:qlwa [2019/08/17 15:31] norman Split out qwa_rndm from qwa_uchk. |
qdosmsq:fs:qlwa [2019/08/22 13:59] (current) norman A few corrections based on qxltool experiments! |
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| |qwa_name|$0004|DC.W $0004,<html><br></html>DC.B 'WIN2'|Disc label| | |qwa_name|$0004|DC.W $0004,<html><br></html>DC.B 'WIN2'|Disc label| | ||
| |qwa_spr0|$001A|DC.W $0000|Spare| | |qwa_spr0|$001A|DC.W $0000|Spare| | ||
| - | |qwa_uchk|$001C|DC.L $EE8C00CE|update check.| | + | |qwa_rndm|$001C|DC.W $EE8C|format random number.| |
| + | |qwa_uchk|$001E|DC.W $00CE|update check.| | ||
| |qwa_intl|$0020|DC.W $0000|interleave factor.| | |qwa_intl|$0020|DC.W $0000|interleave factor.| | ||
| |qwa_sctg|$0022|DC.W $0004|sectors per group.| | |qwa_sctg|$0022|DC.W $0004|sectors per group.| | ||
| Line 135: | Line 136: | ||
| There are not always 65,536 entries in the map - it can be smaller according to the size of the QLWA disc. | There are not always 65,536 entries in the map - it can be smaller according to the size of the QLWA disc. | ||
| + | |||
| + | Given that only (!) 65536 map entries are allowed, this makes an upper limit on the size of a | ||
| + | QXL file. This works out at 255.9 MB which gives an actual maximum size of 255 Mb which results | ||
| + | in 8 sectors per group. | ||
| Each entry in the group has two purposes. The first is to determine where the data is | Each entry in the group has two purposes. The first is to determine where the data is | ||
| Line 518: | Line 523: | ||
| Formatting a QXL.WIN file as a new hard disc is quite a simple process. From a few tests of various sizes of hard disc, I have determined the following process. Each and every sector group in the formatted disc has an entry in the map. | Formatting a QXL.WIN file as a new hard disc is quite a simple process. From a few tests of various sizes of hard disc, I have determined the following process. Each and every sector group in the formatted disc has an entry in the map. | ||
| - | * The size of the disc is used to determine the number of sectors in a group. The minimum appears to be 4 (for a 1 MB disc) and increases by 1 each time the file gets too big to fit into the maximum of 65,536 map entries. | + | * The size of the disc is used to determine the number of sectors in a group. The minimum appears to be 4 (for a 1 MB disc) and increases by 1 each time the file gets too big to fit into the maximum of 65,536 map entries. There is an upper limit of 255 Mb though - otherwise qwa_ngrp will overflow to zero at 256 Mb. (Ask me how I found out!) |
| * The number of sectors in each map entry is calculated as the smallest number that fits into a maximum of 65,536 map entries. Roughly it is the larger of 4 or ((SizeInMb / 32) rounded up to the next whole number if not an exact multiple). | * The number of sectors in each map entry is calculated as the smallest number that fits into a maximum of 65,536 map entries. Roughly it is the larger of 4 or ((SizeInMb / 32) rounded up to the next whole number if not an exact multiple). | ||
| * The map is created in memory as a linked list of words, all pointing at the next word. The last one is set to zero. | * The map is created in memory as a linked list of words, all pointing at the next word. The last one is set to zero. | ||
| Line 589: | Line 594: | ||
| //In order to reduce the length of the page, I've created the table with 4 pairs of columns rather than one. This means that there are not 124 lines, only 32. LOL Read across then down.// | //In order to reduce the length of the page, I've created the table with 4 pairs of columns rather than one. This means that there are not 124 lines, only 32. LOL Read across then down.// | ||
| - | ^ Group Size^ Disc size (Mb)^ ^ Group Size^ Disc size (Mb)^ ^ Group Size^ Disc size (Mb)^ ^ Group Size^ Disc size (Mb)^ | + | ^ Group Size^ Disc size (Mb)^ ^ Group Size^ Disc size (Mb)^ |
| - | | 4| 128| | 5| 160| | 6| 192| | 7| 224| | + | | 4| 128| | 5| 160| |
| - | | 8| 256| | 9| 288| | 10| 320| | 11| 352| | + | | 6| 192| | 7| 224| |
| - | | 12| 384| | 13| 416| | 14| 448| | 15| 480| | + | | 8| 256| | | | |
| - | | 16| 512| | 17| 544| | 18| 576| | 19| 608| | + | |
| - | | 20| 640| | 21| 672| | 22| 704| | 23| 736| | + | |
| - | | 24| 768| | 25| 800| | 26| 832| | 27| 864| | + | |
| - | | 28| 896| | 29| 928| | 30| 960| | 31| 992| | + | |
| - | | 32| 1024| | 33| 1056| | 34| 1088| | 35| 1120| | + | |
| - | | 36| 1152| | 37| 1184| | 38| 1216| | 39| 1248| | + | |
| - | | 40| 1280| | 41| 1312| | 42| 1344| | 43| 1376| | + | |
| - | | 44| 1408| | 45| 1440| | 46| 1472| | 47| 1504| | + | |
| - | | 48| 1536| | 49| 1568| | 50| 1600| | 51| 1632| | + | |
| - | | 52| 1664| | 53| 1696| | 54| 1728| | 55| 1760| | + | |
| - | | 56| 1792| | 57| 1824| | 58| 1856| | 59| 1888| | + | |
| - | | 60| 1920| | 61| 1952| | 62| 1984| | 63| 2016| | + | |
| - | | 64| 2048| | 65| 2080| | 66| 2112| | 67| 2144| | + | |
| - | | 68| 2176| | 69| 2208| | 70| 2240| | 71| 2272| | + | |
| - | | 72| 2304| | 73| 2336| | 74| 2368| | 75| 2400| | + | |
| - | | 76| 2432| | 77| 2464| | 78| 2496| | 79| 2528| | + | |
| - | | 80| 2560| | 81| 2592| | 82| 2624| | 83| 2656| | + | |
| - | | 84| 2688| | 85| 2720| | 86| 2752| | 87| 2784| | + | |
| - | | 88| 2816| | 89| 2848| | 90| 2880| | 91| 2912| | + | |
| - | | 92| 2944| | 93| 2976| | 94| 3008| | 95| 3040| | + | |
| - | | 96| 3072| | 97| 3104| | 98| 3136| | 99| 3168| | + | |
| - | | 100| 3200| | 101| 3232| | 102| 3264| | 103| 3296| | + | |
| - | | 104| 3328| | 105| 3360| | 106| 3392| | 107| 3424| | + | |
| - | | 108| 3456| | 109| 3488| | 110| 3520| | 111| 3552| | + | |
| - | | 112| 3584| | 113| 3616| | 114| 3648| | 115| 3680| | + | |
| - | | 116| 3712| | 117| 3744| | 118| 3776| | 119| 3808| | + | |
| - | | 120| 3840| | 121| 3872| | 122| 3904| | 123| 3936| | + | |
| - | | 124| 3968| | 125| 4000| | 126| 4032| | 127| 4064| | + | |
| - | | 128| 4096| | | | | | | | | | | + | |
norman