Thomas Harte
4c62487e6e
Merge pull request #91 from TomHarte/TableCRC
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Switches to a table-based implementation of CRC generation
2016-12-31 14:16:17 -05:00
Thomas Harte
a147d56ce6
Switched to a table-based implementation of CRC generation, adding construction cost to cheapen running cost.
2016-12-31 14:15:20 -05:00
Thomas Harte
df6e98fa52
Merge pull request #89 from TomHarte/OricDiskWrites
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Adds write support for the Oric .DSK file format
2016-12-31 12:53:43 -05:00
Thomas Harte
52b850a3f5
Quick extra: make sure parsed tracks don't overflow the 6400 byte space available in an MFM disk. Which might be better expressed as 6250?
2016-12-31 12:51:52 -05:00
Thomas Harte
cfbab1448c
Switched to a track parsing that disallows synchronisation values within sector contents.
2016-12-31 12:23:08 -05:00
Thomas Harte
12549ff412
Might as well get the file offset before entering the critical section; also moved the lock guard down more explicitly to group with the second set of actions.
2016-12-31 11:48:46 -05:00
Thomas Harte
6f0b5427e4
Made an attempt to avoid repetition of sync bytes.
2016-12-31 00:20:00 -05:00
Thomas Harte
0123b37213
Made an attempt to include sync values in the stream and properly to align.
2016-12-31 00:11:31 -05:00
Thomas Harte
ea4d85e1cd
The virtual disk constructed is the same across all tracks. So why not just request zero?
2016-12-31 00:10:35 -05:00
Thomas Harte
f217d508b8
Completed first attempt at write support for Oric disk images.
2016-12-30 23:12:46 -05:00
Thomas Harte
1f625fad66
Decided that if this is an [M]FM parsing function then it should be something more intelligent than a mere PLL record. Which I guess conveniently implies Oric DSK-esque behaviour. But properly defined, rather than very vaguely.
2016-12-30 23:10:52 -05:00
Thomas Harte
632b3c63b1
Added the infrastructure necessary for Oric disks to appear writeable to the machine and to receive changed tracks.
2016-12-30 22:51:48 -05:00
Thomas Harte
d581294479
Added get_track
to get the PLL output for a complete track.
2016-12-30 19:59:23 -05:00
Thomas Harte
0f399b0a0c
Made type conversion explicit.
2016-12-30 19:59:01 -05:00
Thomas Harte
c6fcc40ac5
Merge pull request #88 from TomHarte/WDWrites
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Implements write support for the WD.
2016-12-30 18:11:00 -05:00
Thomas Harte
3b29e6a473
Ensured SSD and ADFs are grown if required.
2016-12-30 18:08:12 -05:00
Thomas Harte
07dacff42d
Added writing for Acorn ADF disks, plus appropriate TODOs in both similar bits of boilerplate.
2016-12-30 18:03:30 -05:00
Thomas Harte
c85450648f
Fix: make sure copies have proper event lengths. Also made it much clearer what's going on with the initial copy to the heap.
2016-12-30 17:55:46 -05:00
Thomas Harte
c740d9655a
Fixed: index_count_ may have been left high by a previous call; reset it just in case.
2016-12-30 17:55:06 -05:00
Thomas Harte
d09e7ac1e8
Made an attempt at reacting appropriately if the very first thing that looks like a sector doesn't pan out.
2016-12-30 17:44:35 -05:00
Thomas Harte
5d63556870
Period
s need a custom copy constructor too, if they're going to avoid sharing an event_source.
2016-12-30 17:39:52 -05:00
Thomas Harte
e5cc77f22d
Added an extra sanity check.
2016-12-30 17:29:51 -05:00
Thomas Harte
81a3cbac45
Ensured a copy is passed for writing back rather than the original.
2016-12-30 17:26:44 -05:00
Thomas Harte
63ff5165a4
After a quick bit of reading, discovered the virtual copy constructor pattern really is only a convention in C++, and conformed to it. Which hopefully gives copyable tracks.
2016-12-30 17:25:39 -05:00
Thomas Harte
71dbd78cf2
If asynchronous background processing is to occur on tracks then, given that they inherently have state, they'll need to be copyable, and ideally 'cheaply' (though it's not too great a priority). So started implementing appropriate copy constructors. Also introduced an extra level of indirection to PCMSegmentEventSource
so that it can copy itself without copying the underlying PCMSegment
, which is 95% of the heft of a track in all currently-implemented cases.
2016-12-30 14:23:26 -05:00
Thomas Harte
f88f3c65e9
Removed duplicated newline.
2016-12-30 14:21:36 -05:00
Thomas Harte
82bb78fb2d
Ensured that get_sector copes even if any invalid sectors are encountered.
2016-12-30 14:21:14 -05:00
Thomas Harte
6fc692cd34
Attempted to switch to an asynchronous means for continuous file updates. Testing with SSD, as usual.
2016-12-29 22:15:58 -05:00
Thomas Harte
bbd94749f4
... and I guess an instant maximal simplification is also easy if length ends up being 0
2016-12-29 11:02:21 -05:00
Thomas Harte
54900ca3fb
Addition and subtraction can end immediately without performing any extra work if the operand is 0
2016-12-29 11:00:47 -05:00
Thomas Harte
a8bc9d830e
Removed leftover very temporary debugging aid.
2016-12-28 23:03:05 -05:00
Thomas Harte
b9fad184d7
Added just enough for a complete manual test of writing to a .ADF with the 1770 then getting the correct result parsing it back on the host side in order potentially to update a file.
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... which means that now it's time to worry about when and how mounted files should actually update themselves. Which will make for some fun with threading, I dare say.
2016-12-28 23:00:47 -05:00
Thomas Harte
af1b396c9e
Found an ugly issue with Storage::Time
as implemented (i) to be unsigned; and (ii) automatically to simplify. Will need to fix. Here's a quick workaround for this one segment of code.
2016-12-28 22:57:11 -05:00
Thomas Harte
9cb902cc4f
Experimentally marked ADF as writable too, immediately discovering a mistake in the analysing MFM decoder.
2016-12-28 22:34:22 -05:00
Thomas Harte
e4000bd060
Added some even more verbose logging; slightly simplified write loop logic, and decided it's definitely write_byte
that's responsible for CRC generator feeding.
2016-12-28 21:24:19 -05:00
Thomas Harte
ce814c9e99
These can be const.
2016-12-28 21:23:22 -05:00
Thomas Harte
bfe6c0a0c1
Ensured that FileHolder
gets a writeable file reference if one is possible, and records whether the file in hand is read-only. So now the SSD class can answer honestly.
2016-12-28 20:09:14 -05:00
Thomas Harte
4adcb46665
Fixed FM-mode CRC generation.
2016-12-28 19:51:27 -05:00
Thomas Harte
46a93d2e12
Fixed errors to ensure that FM disks, at least, follow the same CRC generation rules when being built from sectors and when being parsed.
2016-12-28 19:48:46 -05:00
Thomas Harte
1277a67f9a
Introduced data_mode_ to replace is_reading_data_, representing that there are now three possible modes. When writing, any input from the read head won't affect the CRC generator.
2016-12-28 19:26:21 -05:00
Thomas Harte
720b1e5802
Attempted to ensure proper CRC generation for FM-format input.
2016-12-28 18:56:53 -05:00
Thomas Harte
8cd1575891
Similar fix to that over in Oric land: ensure a known, effective initial value for the Plus 3's control register.
2016-12-28 18:52:36 -05:00
Thomas Harte
3a9ad3fb08
Fixed Oric .DSK handling, per my latest understanding. Which creates a desire to write shorts directly to the disk surface, so exposed that in the encoder.
2016-12-28 18:50:28 -05:00
Thomas Harte
90151e2094
Fixed to ensure a known initial control register value, which has taken effect.
2016-12-28 18:49:32 -05:00
Thomas Harte
7a627b782d
Reintroduced writing of MFM sync marks when writing a sector.
2016-12-28 18:48:50 -05:00
Thomas Harte
a568172758
Made steps towards proper CRC generation. Am currently comparing against Oric disk images, as — amongst other things — they include precomputed CRCs.
2016-12-28 18:29:37 -05:00
Thomas Harte
99993a1b24
Since it's about to become important that objective results match, added a couple of objective-result tests for the CRC generator.
2016-12-27 19:03:46 -05:00
Thomas Harte
9c0f622a2e
Started working CRC checking into the 1770. Discovered immediately that my generated CRC does not match that built into the Oric disk images. So mine is pretty-much certainly wrong. An opportunity for learning!
2016-12-26 16:46:26 -05:00
Thomas Harte
0490a47058
Worked on the all-around framework for decoding sectors back from tracks when closing down a file. Hit the wall that the parser is more observant of CRCs than the WD. No, really. So I guess I have to stop avoiding that whole issue.
2016-12-26 14:24:33 -05:00
Thomas Harte
83c433c142
Deviated from the data sheet, which seems likely to be correct. Hence removed a whole load of the temporary logging.
2016-12-26 12:48:49 -05:00