487fe83dca
Ensures that vertical sync and end-of-visible-lines conditions potentially trigger whenever line_counter_ changes, not only when it increments.
2017-08-26 17:54:54 -04:00
6c5a03187b
Relocates the HSYNC start test, in order to pass Arnold's cpctest HSYNC start position conformance test.
2017-08-26 17:22:48 -04:00
7d7aa2f5d5
Eliminates repetition of the unpacking of register 3 into a horizontal sync count.
2017-08-26 14:37:03 -04:00
28550c0227
Breaks the 6845 bus cycle into a phase 1 and a phase 2 per the belief that sync line changes, which are observable, happen at the end of the first phase rather than at the beginning of the next. This may have interrupt timing effects, as machines often derive an interrupt from sync.
2017-08-26 13:56:23 -04:00
6e99169348
Permits the 6845's bus state to be examined by an owner, eliminating the need to buffer it in the bus handler. But more than that it allows the CRTC to decide when it adjusts the various outputs respective to the main phase. So a net effect of the change is that the CPC now sees vsync a cycle earlier, because my current reading of the 6845 datasheet is that it is set at the end of phase 1, not the beginning of the next phase 1.
2017-08-26 12:59:59 -04:00
3caa4705ca
Limits sync counter size.
2017-08-26 12:31:19 -04:00
039aed1bd1
Switches the two sync counters to upward-going rather than downward, as a more likely match to the way the rest of the 6845 implementation.
2017-08-25 21:26:01 -04:00
a914eadc85
Ensured that register 6 is checked on every loop.
2017-08-22 22:17:45 -04:00
e956740c56
Refactors the 6845 more clearly to break out the acts of ending a line and ending a frame, changing the way the memory address is altered — the end-of-line value is provisionally stored and then used if necessary — in order to do so.
2017-08-22 21:54:48 -04:00
e88a51e75e
Worked logic all the way down to the CPC. If the 8272 announces that it is asleep, it is now no longer clocked. Also very slightly cut down on IRQ line chatter to the Z80.
2017-08-20 12:05:00 -04:00
2d9efccc98
Introduced a master 'is sleeping' flag. I'm starting to think there's a pattern forming here.
2017-08-20 10:43:53 -04:00
8ce46b6e49
Having spotted that I was using my single-character loop counter names incorrectly (quelle surprise!), got a bit more explicit. Also flattened into a single loop so that I can break rather than returning.
2017-08-20 10:32:09 -04:00
669e0caff5
Ensured the head_unload_delay values are properly seeded, and generalised the quick escape.
2017-08-19 22:06:56 -04:00
e208f03636
Corrects the US colour palette, effectively undoing what was a mistaken adjustment for the time when Oric-centric phase alignment was built into the CRT based on a false calculation that it wouldn't affect the machines that generate chrominance functionally.
2017-08-16 09:58:34 -04:00
cc9d23f23b
Inverted meaning of register_masks, as it's a bit weird that the mask is inverted immediately upon usage. It's a left-over from thinking the unused bits should be 1s; unit tests reveal they should be 0s. Comment updated appropriately.
2017-08-16 09:29:48 -04:00
1a831bcf9b
Quick fix: supply the port being written to correctly.
2017-08-16 09:15:57 -04:00
82367a2246
Added documentation.
2017-08-16 09:14:56 -04:00
3947347d88
Introduces active input handling for the AY and uses it in the CPC to give proper, active keyboard input, rather than push-on-select, which was only ever a temporary hack. Also maps a few more keys for the Amstrad.
2017-08-15 22:47:17 -04:00
aefbafa18d
Centralised the 8272's actions of setting the non-DMA execution flag, picking the drive and head and loading the head for accessing commands, and switched error flag if read ID doesn't find anything.
2017-08-15 21:49:10 -04:00
d12c834f9c
Increased amount reported.
2017-08-15 20:35:33 -04:00
56de5cb2b3
Removed one further logging event.
2017-08-15 20:18:32 -04:00
709257a0c5
Quick fix: also treat reception of sync as a reason not to stop looking for a data address mark.
2017-08-15 20:16:56 -04:00
75a9d2bb33
Started withdrawing logging, reduced index hole count back to the correct number and tried to increase read_data rigour.
2017-08-15 20:12:01 -04:00
73080d6c36
Added an easy way for disk controllers to clamp termination of written data exactly to the index hole.
...
This commit also temporarily provides a whole load of extra logging and minor logic improvements from the 8272. I'm mid-flow on finding a particularly vicious error in its handling of writing; wait for the pull request. But, at least: now waits for the first part of a post-ID gap before writing data, and attempts partially to handle appearance of the index hole during writing a track. More work to do on that though.
2017-08-15 16:05:10 -04:00
9d77f33611
Dealt with another source of repeating magic constants: the command numbers.
2017-08-15 11:06:10 -04:00
7d132f81f7
Increased logging by quite a distance and made an attempt once again to allow the processor some time to supply the first byte when writing before declaring overrun.
2017-08-15 10:50:28 -04:00
6553bf05b4
Corrected multi-sector reads: ensured the incremented sector number isn't replaced by the original, and that the controller returns to scanning mode.
2017-08-14 22:27:31 -04:00
0816d3f5a9
Corrected 'read deleted data' command. It's 0xc, not 0xb.
2017-08-14 21:41:20 -04:00
55055c7847
Minor: ensured immediate line comparison works. But I think my problem might be trying to do this as straight line logic?
2017-08-14 19:08:20 -04:00
cddcd0fb79
Put my money where my mouth is and switched the superclass of WD1770 to MFMController, eliminating duplicated (/factored out) code.
2017-08-14 16:32:53 -04:00
a366298022
Factored out the standard [M]FM gap and mark groups, to increase 8272 readability and because it's pretty-much certain I'll need them again if ever I try to tackle e.g. the 8271.
2017-08-14 16:03:35 -04:00
4df9307d25
Factored out the dull and repetitious stuff of writing n bytes of the same value.
2017-08-14 15:50:36 -04:00
9038ba622e
Added a quick version of read track.
2017-08-14 14:34:56 -04:00
7b8bb0297a
Implemented single density version of format track.
2017-08-14 13:03:17 -04:00
0da02d3902
Added read/write escape clauses if faced with a read-only disk.
2017-08-14 12:53:18 -04:00
2e5ad19fe1
Minor tidying.
2017-08-14 12:42:48 -04:00
a10389a22c
Factored out the stuff of stuffing the bus.
2017-08-14 12:42:22 -04:00
cefec7a19f
Sought more robustly (i.e. less repetitively) to handle dispatch, including cancelling seeks where appropriate.
2017-08-14 10:37:39 -04:00
7264fbb3d2
read_id now clears status. I probably need to find a way to generalise this.
2017-08-14 09:58:55 -04:00
8a7b23dc9e
Ensured data-accessing commands cancel seeks on their drives. Also introduced a count of drives currently seeking in order to make for a slightly better broad-phase test in run_for.
2017-08-14 09:45:39 -04:00
b7065575f3
Added (empty) call-ins for DMA usage; switched to having the 'is seeking' bit in the status register stay high until sense interrupt status, but now it goes high even for seeks that don't actually go anywhere, and corrected interpretation of the specify command, with a positive result: the received step rate time, now that it's being interpreted correctly, is much shorter.
2017-08-14 09:04:22 -04:00
7ea703f150
Started making provisions for a DMA-compatible implementation. Re: the CPC, it sounds like DMA acknowledge might be permanently wired, causing DMA mode seemingly to work from the 8272's point of view.
2017-08-14 08:38:00 -04:00
1011143dbe
Sought to correct my interpretation of 'gap 3'.
2017-08-13 21:52:48 -04:00
9ace6e1f71
Applied minimum constraints for specified parameters.
2017-08-13 19:25:57 -04:00
5221837be8
Fixed Non-DMA flag for the format track execution phase. The emulated machine now provides sector details.
2017-08-13 18:51:06 -04:00
e1e9a06712
Made an attempt at format a track.
2017-08-13 18:05:19 -04:00
b0a7208cc7
Strung together a very basic version of 8272 write [/deleted] data. Lots of cases as-yet unhandled.
2017-08-13 12:50:07 -04:00
eec42aa7ae
Entrusted further status to drives; also adjusted them to report read only if diskless, which I now believe to be correct.
2017-08-13 11:50:49 -04:00
5f42022c1d
Added a tester for the control mark.
2017-08-12 17:35:14 -04:00
11d0c37506
Attempted to find a more expressive way for maintaining state — macros for all conditions, to bind both values and destinations.
2017-08-12 17:33:52 -04:00
Thomas Harte