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378 Commits

Author SHA1 Message Date
Thomas Harte
d9071ee9f1 Starts sketching out the asynchronous bus. 2019-04-29 13:45:53 -04:00
Thomas Harte
97e118abfa Corrects accidental exclusion of MOVE.bw (xxx).w, [(xxx).w/(xxx).l]. 2019-04-28 23:25:46 -04:00
Thomas Harte
412f091d76 Implements a missing form of BTST. 2019-04-28 23:20:50 -04:00
Thomas Harte
ca1f669e64 Implements MOVEP. 
371 is now the alleged number of missing opcodes. But I'd dare imagine it's more like three or four.
 2019-04-28 22:52:54 -04:00
Thomas Harte
0298b1b3b7 Implements LINK and UNLINK. 
Also starts excluding opcodes that I can't determine the mapping of from the list of those tested against.

Due to those two things together, the latter incomplete: 627 opcodes outstanding. But only STOP and MOVEP remain on my list of things to implement prior to exceptions.
 2019-04-28 17:12:31 -04:00
Thomas Harte
4b1324de77 Takes a run at TRAPV. 
... to leave 1466 as the unimplemented count.
 2019-04-28 15:52:58 -04:00
Thomas Harte
8e8dce9bec Attempts an implementation of CHK. 
1467 is now the official count of things to implement, though I'm starting to get suspicious.
 2019-04-28 15:47:21 -04:00
Thomas Harte
f4350522bf Implements NBCD. 
Now outstanding: 1891.
 2019-04-27 21:29:50 -04:00
Thomas Harte
e2abb66a11 Adds missing addressing modes for ADDA and SUBA. 
... reducing missing opcodes to 1941.
 2019-04-27 17:22:26 -04:00
Thomas Harte
ab5fcab9bf Attempts an implementation of ADDX and SUBX. 
Leaving 2005 non-[A/F]-line instructions.
 2019-04-27 16:57:47 -04:00
Thomas Harte
e75b386f7d Attempts DIVU and DIVS. 
Reportedly leaving 10965 operations now unimplemented.
 2019-04-26 22:22:35 -04:00
Thomas Harte
796203859f Implements PEA. 
This decreases the unimplemented count by 28 from 11841 to 11813.
 2019-04-26 13:49:59 -04:00
Thomas Harte
a3b6d2d16e Corrects test and resolves all instances of opcodes that are valid but shouldn't be. 
The converse case will require implementation of the remaining instructions.
 2019-04-25 22:54:58 -04:00
Thomas Harte
3983f8303f Introduces failing test of 68000 opcode coverage. 2019-04-25 22:06:05 -04:00
Thomas Harte
dab9bb6575 Implements EXT. 2019-04-25 18:22:19 -04:00
Thomas Harte
c132bda01c Implements MOVE from SR. 2019-04-25 14:39:32 -04:00
Thomas Harte
4e25bcfcdc Corrects decoding of AND/OR x, Dn. 2019-04-25 14:19:13 -04:00
Thomas Harte
ea463549c7 Corrects overflow flag for LSL and LSR. 2019-04-25 13:59:10 -04:00
Thomas Harte
723acb31b3 Corrects various flag issues with ADD, SUB and NEG. 2019-04-25 13:53:23 -04:00
Thomas Harte
5725db9234 Corrects calculated-address TAS. 2019-04-25 12:42:05 -04:00
Thomas Harte
8557e563bc Takes a run at TAS, clarifying bus cycles. 2019-04-25 12:19:40 -04:00
Thomas Harte
d2491633ce Ensures MOVEM to M .w correctly updates A7. 2019-04-24 23:21:15 -04:00
Thomas Harte
002796e5f5 Takes a run at BSET and BCHG. 2019-04-24 23:01:32 -04:00
Thomas Harte
fa0accf251 Attempts to correct flags for ASL, ASR, LSL, LSR. 2019-04-24 21:04:47 -04:00
Thomas Harte
dcb8176d90 Corrects potential failure properly to set stack pointer state. 2019-04-24 17:58:27 -04:00
Thomas Harte
be32b1a198 Fixes JSR (An) return address [again]. 2019-04-24 17:50:38 -04:00
Thomas Harte
582e4acc11 Implements ANDI/ORI/EOR to SR/CCR. 2019-04-24 17:38:59 -04:00
Thomas Harte
10f75acf71 Causes EXG to function. 2019-04-24 16:32:16 -04:00
Thomas Harte
b9933f512f Fixed: the word/long-word bit works the other way around. 2019-04-24 16:30:15 -04:00
Thomas Harte
75a7f7ab22 Inserts missing program fetch for CMPI.bw #, (d8/16...). 2019-04-24 14:45:24 -04:00
Thomas Harte
e214584c76 SWAP should clear overflow and carry. 2019-04-24 13:19:56 -04:00
Thomas Harte
0bb6b498ce Simplifies and fixes post-inc MOVE behaviour. 2019-04-24 13:14:25 -04:00
Thomas Harte
958d44a20d Causes SWAP actually to perform. 2019-04-24 13:06:12 -04:00
Thomas Harte
bb9424d944 Corrects byte increment/decrement actions for A7. 2019-04-24 13:01:08 -04:00
Thomas Harte
11bf706aa2 Attempts to fix LT and LTE conditions. 2019-04-24 10:07:17 -04:00
Thomas Harte
033b8e6b36 ADD/SUBQ #, An shouldn't set flags. 
Also, temporarily at least, adds a new means for observing CPU behaviour.
 2019-04-24 09:59:54 -04:00
Thomas Harte
7c3ea7b2ea Resolves additional byte accesses being signalled as word. 2019-04-23 21:23:20 -04:00
Thomas Harte
a08043ae88 Ensures that MOVE.b #, (xxx).l writes only a byte. 
Also rearranges some of the temporary logging functionality.
 2019-04-23 19:01:58 -04:00
Thomas Harte
7c132a3ed5 Ensures 16-bit values of Xn for (d8, An, Xn) are sign extended. 2019-04-22 22:13:02 -04:00
Thomas Harte
20e774be1e Corrects return address of JSR (An). 2019-04-22 21:11:49 -04:00
Thomas Harte
6d6046757d Fixes predecrementing MOVEM to leave the proper address in the relevant register. 2019-04-22 15:41:09 -04:00
Thomas Harte
55073b0a52 Corrects a bunch of MOVEs to (d8/16, PC/An, [Xn]). 2019-04-21 22:55:23 -04:00
Thomas Harte
44eb4e51ed Ensures DBcc properly signals program fetches. 2019-04-21 22:54:20 -04:00
Thomas Harte
3cb042a49d Corrects the carry and extend flags for various long-word operations. 2019-04-21 22:08:18 -04:00
Thomas Harte
b78ea7d24c Further simplifies CMPA. 2019-04-20 21:23:36 -04:00
Thomas Harte
c66728dce2 Corrects decoding of CMPA. 2019-04-20 21:21:33 -04:00
Thomas Harte
0be9a0cb88 Corrects Scc (and other conditionals) for complex addressing modes. 2019-04-20 18:35:19 -04:00
Thomas Harte
a90f12dab7 Corrects return address for TRAP. 2019-04-20 15:49:32 -04:00
Thomas Harte
ef33b004f9 Corrects word access order of MOVEM.l. 2019-04-20 15:13:12 -04:00
Thomas Harte
2cac4b0d74 Corrects EA usage for ADDA and SUBA. 2019-04-19 23:02:41 -04:00
Thomas Harte
a49f516265 Corrects direction of MOVE [to/from] USP. 2019-04-19 22:41:06 -04:00
Thomas Harte
2d97fc1f59 Beefs up documentation and developer support. 2019-04-19 13:29:35 -04:00
Thomas Harte
9ef7743205 Attempts to unify type decoding a little further. 2019-04-19 13:29:20 -04:00
Thomas Harte
ee7ae11e90 Implements EXG and SWAP. 2019-04-19 11:27:43 -04:00
Thomas Harte
f67d7f1db5 Adds the final (!) set of missing MOVEs. 2019-04-19 11:11:38 -04:00
Thomas Harte
99981751a2 Adds the official NOP. 
Which is a freebie.
 2019-04-18 23:46:01 -04:00
Thomas Harte
ffdf02c5df Adds MOVE XXX.lw, -(An) 2019-04-18 23:40:54 -04:00
Thomas Harte
27c7d00a05 Commutes final missing MOVEs to TODOs. 2019-04-18 23:35:32 -04:00
Thomas Harte
64c4137e5b Begins a cleanup procedure on MOVE. 2019-04-18 23:25:19 -04:00
Thomas Harte
8c26d0c6e6 Makes an attempt at RTE and RTR. 2019-04-18 20:50:58 -04:00
Thomas Harte
81dcfd9f85 Implements AND, OR and EOR. 
As well as introducing a little more nuance to the double-decoding test.
 2019-04-18 16:34:48 -04:00
Thomas Harte
9334557fbf Added important TODO. 2019-04-17 23:12:32 -04:00
Thomas Harte
b09de8efce Attempts to fill in the rest of MOVE x, -(An). 2019-04-17 23:05:16 -04:00
Thomas Harte
5a50eb56dd Marginally increases coverage of MOVE x, -(An). 2019-04-17 22:30:07 -04:00
Thomas Harte
e49b257e94 Takes a run at TRAP. 2019-04-17 22:21:56 -04:00
Thomas Harte
b8a0f4e831 Implements MOVE to/from USP. 2019-04-17 16:58:59 -04:00
Thomas Harte
29f8dcfb40 Fixes a bunch of (d16, An)-type MOVEs and implements MOVE (XXX).wl, (d16,An)/etc. 2019-04-17 16:13:35 -04:00
Thomas Harte
0c05983617 Shortens impact of MULU on the instruction stream to correct parsing. 
I need to look into this.
 2019-04-17 15:15:48 -04:00
Thomas Harte
0bd653708c Corrects MOVE.bw Dn, (An)[+]. 2019-04-17 14:31:20 -04:00
Thomas Harte
41d800cb63 Fixes ADD/SUB Dn,x to use the proper destination value. 2019-04-17 10:23:47 -04:00
Thomas Harte
cadc0bd509 Mental delusion lifted: JSR doesn't look enough like BSR. 2019-04-17 10:02:14 -04:00
Thomas Harte
b64da2710a Corrects a few MOVE #s. 2019-04-17 10:00:14 -04:00
Thomas Harte
82b08d0e3a Corrects addressing behaviour of nRd[+-]. 2019-04-17 08:53:34 -04:00
Thomas Harte
8f77d1831b Implements MULU and MULS. 2019-04-16 22:16:43 -04:00
Thomas Harte
be722143e1 Completes addressing modes for ADDI/etc/etc. 2019-04-16 21:34:16 -04:00
Thomas Harte
d8d974e2d7 Consolidates JSR and BSR preparation. 2019-04-16 21:29:37 -04:00
Thomas Harte
9b7ca6f271 Implements the basics of EORI, ORI, ANDI, SUBI and ADDI. 
Also corrects the BSR return address.
 2019-04-16 19:50:10 -04:00
Thomas Harte
8ce018dbab Adds the necessary runtime support for AND, EOR and OR. 2019-04-16 15:17:40 -04:00
Thomas Harte
180062c58c Finishes fleshing out [ADD/SUB]Q. 2019-04-16 14:28:31 -04:00
Thomas Harte
37656f14d8 Adds basic addressing modes for [ADD/SUB]Q. 2019-04-16 11:19:45 -04:00
Thomas Harte
dec5535e54 Implements (arguably: fixes) BSR. 2019-04-15 23:20:36 -04:00
Thomas Harte
1f0e3b157a Corrects a couple of JSR and JMP addressing modes. 2019-04-15 22:37:11 -04:00
Thomas Harte
d802e83f49 Fills in further MOVEs. 2019-04-15 22:25:22 -04:00
Thomas Harte
ebcae25762 Adjusts JSR behaviour and further extends MOVE. 2019-04-15 22:02:52 -04:00
Thomas Harte
5330267d16 Implements BCLR. 2019-04-15 18:11:02 -04:00
Thomas Harte
892476973b Attempts RO{X}[L/R]. 2019-04-15 17:31:58 -04:00
Thomas Harte
84f4a25bc9 Completes TST. 2019-04-15 16:28:20 -04:00
Thomas Harte
1460a88bb3 Takes a run at JSR and RTS. 2019-04-15 15:14:38 -04:00
Thomas Harte
d25ab35d58 Finally gets setw usage correct. 2019-04-15 12:41:56 -04:00
Thomas Harte
a223cd90a1 Adds predecrement TSTs, increases QL running time, reduces logging. 2019-04-15 12:36:08 -04:00
Thomas Harte
aef92ba29c Corrects immediate shift count. 2019-04-15 12:25:45 -04:00
Thomas Harte
328d297490 Implements the first few addressing modes for TST. 2019-04-15 10:03:52 -04:00
Thomas Harte
3d240f3f18 Corrects decoding of DBcc. 2019-04-15 09:49:23 -04:00
Thomas Harte
45f35236a7 Corrects decoding of ADDA and SUBA. 2019-04-15 09:44:06 -04:00
Thomas Harte
fba210f7ce Corrects MOVE.l Dn, (An)[+]. 2019-04-15 09:30:49 -04:00
Thomas Harte
8a09e5fc16 Implements Scc. 2019-04-14 22:39:13 -04:00
Thomas Harte
75d8824e6b Eliminates implicit type conversion. 2019-04-14 21:02:28 -04:00
Thomas Harte
325af677d3 Implements MOVEM to M with an implicit type conversion. 2019-04-14 20:53:27 -04:00
Thomas Harte
1003e70b5e Implements MOVEM to R. 2019-04-14 20:02:18 -04:00
Thomas Harte
d70229201d Advances right up to the lack of MOVEM actions being the final piece. 2019-04-14 14:45:29 -04:00
Thomas Harte
823f91605b Still slow pedalling slightly, adds further MOVEM storage. 2019-04-14 14:31:13 -04:00
Thomas Harte
53f75034fc Commits at least to decoding MOVEM. 2019-04-14 14:09:28 -04:00
Thomas Harte
78649a5b54 Fleshes out MOVE, (XXX) a little further. 2019-04-12 17:16:03 -04:00
Thomas Harte
f48db625a0 Corrects write-back and zero flag for ADD/SUB.l. 2019-04-12 16:41:00 -04:00
Thomas Harte
2ba66c4457 Corrects MOVEA, adds extra test safeguards. 2019-04-12 16:10:17 -04:00
Thomas Harte
2c78ea1a4e Completes conversion away from magic constants. 2019-04-12 15:48:29 -04:00
Thomas Harte
73f50ac44e Commits further to elimination of magic constants. 2019-04-12 13:45:28 -04:00
Thomas Harte
9ce48953c1 Improves debugging printout. 2019-04-12 13:45:03 -04:00
Thomas Harte
1098cd0c6b Begins rooting out magic constants. 2019-04-11 22:31:17 -04:00
Thomas Harte
652ebd143c
Corrects addressing mode support for LEA. 2019-04-11 11:58:34 -04:00
Thomas Harte
8e9d7c0f40 Corrects register-relative address calculation. 2019-04-10 23:09:03 -04:00
Thomas Harte
a64948a2ba Permits zero-bus-op non-terminals. 2019-04-10 22:42:43 -04:00
Thomas Harte
43f619a081 Implements ASL, ASR, LSL and LSR. 2019-04-10 22:31:04 -04:00
Thomas Harte
a07de97df4 Implements the fixed part of register shifts. 2019-04-09 22:12:37 -04:00
Thomas Harte
85d25068a8 Attempts a full implementation of memory shifts. 2019-04-09 22:04:25 -04:00
Thomas Harte
7a0319cfe5 Kicks the work of dealing with ASL/etc into the runtime. 2019-04-09 21:48:08 -04:00
Thomas Harte
f750671f33 Stepping gingerly onwards, adds a double-decoding test. 
As a result of that, collapses BRA into Bcc. Which provisionally looks correct.
 2019-04-09 16:54:41 -04:00
Thomas Harte
7886fe677a Cleans up commenting. 2019-04-08 22:51:18 -04:00
Thomas Harte
73c027f8e3 Implements CMPA and CMPM. [Provisionally] completing the CMPs. 2019-04-08 22:40:38 -04:00
Thomas Harte
eda88cc462 Implements MOVE to CCR. 2019-04-07 22:24:17 -04:00
Thomas Harte
652f4ebfed Implements CLR, NEG, NEGX and NOT. 2019-04-07 22:07:39 -04:00
Thomas Harte
06a2f59bd0 Implements DBcc. 2019-04-06 23:21:01 -04:00
Thomas Harte
03f365e696 Corrects source/destination order of CMP setup. 2019-04-06 20:00:15 -04:00
Thomas Harte
49a22674ba Corrects MOVE destinations. 2019-04-06 18:33:53 -04:00
Thomas Harte
ec494511ec Implements CMP. 2019-04-06 10:41:19 -04:00
Thomas Harte
af02ce9c6e Attempts to correct various instances of PC-relative addressing. 2019-04-05 23:49:13 -04:00
Thomas Harte
56e42859ab Ensures the supervisor flag is updated properly on MOVE to SR. 2019-04-05 23:21:50 -04:00
Thomas Harte
2d153359f8 Adds BTST. 2019-04-04 21:43:22 -04:00
Thomas Harte
068ce23716 Adds a few more MOVEs. 2019-04-04 19:49:19 -04:00
Thomas Harte
03be2e3652 Adds decoding of ADDA and SUBA. 2019-04-03 22:39:01 -04:00
Thomas Harte
4ef2c0bed8 Completes ADD and SUB. 2019-04-03 21:41:59 -04:00
Thomas Harte
bfd405613c Reuse of addresses is also no longer implicit. 2019-04-03 21:27:11 -04:00
Thomas Harte
73e1c8c780 Corrects now-unimplemented ADD/SUB. 2019-04-03 19:43:54 -04:00
Thomas Harte
689ba1d4a2 Effective address adjustments now have to be explicit. 2019-04-03 19:13:10 -04:00
Thomas Harte
39b9d00550 Moves some way towards mapping out ADD and SUB, fixing a bug with address register modification. 2019-04-02 21:50:58 -04:00
Thomas Harte
64f99d83a4 Takes a stab at offering ADD, ADDA, SUB and SUBA operations. 
Not yet decoded.
 2019-04-01 21:21:26 -04:00
Thomas Harte
8f1faefa1c Implements further MOVEs and fixes a potential error in program formation. 2019-03-31 22:34:28 -04:00
Thomas Harte
a9ceef5c37 Improves communication slightly. 2019-03-31 22:27:33 -04:00
Thomas Harte
c6f977ed4b Corrects CMPI and documentation; implements JMP. 2019-03-31 21:13:26 -04:00
Thomas Harte
cb240cd32a Switches to a more explicit tokeniser, to allow for greater flexibility momentarily. 2019-03-30 23:11:39 -04:00
Thomas Harte
bc6349f823 Adds RESET, fixes branches and attempts to fix CMPI. 2019-03-29 23:40:54 -04:00
Thomas Harte
a93a1ae40f Completes MOVE.blw <ea>, Dn/An/(An)/(An)+, implements MOVEq. 2019-03-29 23:13:41 -04:00
Thomas Harte
25254255fe Implements a few additional MOVEs. 2019-03-27 21:26:04 -04:00
Thomas Harte
42634b500c Implements LEA. 2019-03-26 22:07:28 -04:00
Thomas Harte
be4b38c76a Adds BRA and Bcc. 2019-03-25 22:54:49 -04:00
Thomas Harte
7163b1132c Takes a run at CMPI. 
Also factors out a couple of mode things, clarifies on where things from the
prefetch are assembled to, and switches to ordering implemented instructions
alphabetically.
 2019-03-24 23:05:57 -04:00
Thomas Harte
3ccec1c996 Implements MOVE to SR, fleshing out the final bits of storage for the status word. 2019-03-24 18:20:54 -04:00
Thomas Harte
47359dc8f1 Adds tests for MOVE.l (An), Dn, and thereby correct their implementation. 2019-03-23 21:41:47 -04:00
Thomas Harte
43532c8455 Starts to make incursions into MOVE[A].l. 2019-03-23 21:03:52 -04:00
Thomas Harte
d7c3d4ce52 Adds test for MOVEA.w (0x1000), A1 and fixes implementation thereof. 2019-03-22 23:27:48 -04:00
Thomas Harte
ed7060a105 Made an initial stab at completing MOVEA.w. 
I think I'm probably peeking into the prefetch queue incorrectly.
 2019-03-22 21:43:51 -04:00
Thomas Harte
db0da4b741 Improves get/set state. 2019-03-22 19:34:17 -04:00
Thomas Harte
c9c16968bb Implements MOVEA as distinct from MOVE. 
At least as far as MOVE is implemented, that is.
 2019-03-22 19:25:53 -04:00
Thomas Harte
fdc598f2e1 Starts MOVE tests; in pursuit of which talks the 68000 into obeying run lengths. 2019-03-21 22:30:41 -04:00
Thomas Harte
f679145bd1 Makes a further push into the MOVEs. 
With some quick notation shortening.
 2019-03-20 23:21:02 -04:00
Thomas Harte
eeb161ec51 Converts the prefetch queue into a 32-bit quantity. 2019-03-19 21:33:52 -04:00
Thomas Harte
21cb7307d0 Adds MOVE #, Dn and MOVEA An, An. 
As well as the scheduling for `(d16,PC), Dd` and `MOVE (d8,As,Xn), Dd` other than the .ls.
 2019-03-19 11:53:37 -04:00
Thomas Harte
412a1eb7ee Takes an initial run at (An)+, -(An), (d16,An) and (d8,An,Xn) addressing modes. 
With only MOVEs from those to a data register implemented so far.
 2019-03-18 22:51:32 -04:00
Thomas Harte
1d801acf72 Switched to a better ABCD fix. 2019-03-17 22:04:32 -04:00
Thomas Harte
0d7bbdad54 Begins a basic get/set state API, allowing some actual unit tests, implying an ABCD fix. 2019-03-17 21:57:00 -04:00
Thomas Harte
53b3d9cf9d Implements a few more MOVE variants, plus MOVEA. 2019-03-17 14:34:16 -04:00
Thomas Harte
c3ebbfb10e Implements all MOVE Dn, Dn. 2019-03-16 23:14:18 -04:00
Thomas Harte
58f035e31a Makes error more communicative. 2019-03-16 23:05:12 -04:00
Thomas Harte
a8f1d98d40 Small further adjustments; seems likely to be correct now. 2019-03-16 23:01:56 -04:00
Thomas Harte
cf6fa98433 Corrects detection of terminal micro-ops. 2019-03-16 22:50:44 -04:00
Thomas Harte
937b3ca81d Attempts properly to honour the bus-op and microcycle contract. 2019-03-16 22:36:09 -04:00
Thomas Harte
d0c5cf0d2d Starts attempting to kill the need to prepare all bus step sequences in advance. 2019-03-16 21:47:46 -04:00
Thomas Harte
4cbf2bef82 By way of a friend, clears a bunch of transient stuff out of 68000Storage.hpp. 
As, even if not in the programmer's eye, this does affect recompilation times.
 2019-03-16 19:41:07 -04:00
Thomas Harte
388d808536 Switches to providing UDS and LDS implicitly via address. 
Also makes sure that the difference between a non-data cycle that starts without the address strobe active and one that starts with it active can be discerned.
 2019-03-16 17:54:58 -04:00
Thomas Harte
720aba3f2d Adds an implementation of SBCD and slightly neatens syntax for building programs. 2019-03-14 21:22:02 -04:00
Thomas Harte
f9101de956 This might very well be the 68000's first real gasp: performing an ABCD. 2019-03-14 19:32:15 -04:00
Thomas Harte
bb04981280 I'm still dithering on address management, but this seeks fully to implement ABCD and SUBD bus programs. 2019-03-13 21:08:13 -04:00
Thomas Harte
57898ed6dd This is where my thinking now resides. Two levels of indirection, and consolidated collections. 2019-03-12 22:46:31 -04:00
Thomas Harte
33b53e7605 Settles upon disassembly as the route in, and begins work in that direction. 2019-03-11 22:47:58 -04:00
Thomas Harte
89c71f9119 Introduces EmuTOS, and starts constructing test cases around it. 2019-03-10 18:40:12 -04:00
Thomas Harte
98aa597510 A theoretical 68000 could now perform its /RESET. That's all though. 2019-03-10 17:42:13 -04:00
Thomas Harte
de56d48b2f Embraces a more communicative 68000 bus. 2019-03-10 17:27:34 -04:00
Thomas Harte
b9b52b7c8b Begins some very early sketching out of a 68000. 2019-03-09 00:00:23 -05:00