Peter Evans
b2bfee7f96
The SLOTCXROM switch seems to work opposite
...
Which seems weird, but I've verified this in some other places.
2018-01-29 00:30:12 -06:00
Peter Evans
418688cd15
Lock disk drives during disassembly
2018-01-28 18:06:14 -06:00
Peter Evans
33b44d1a70
selected_drive will now have a default value (of drive1)
2018-01-27 21:53:12 -06:00
Peter Evans
2c3d6a4dfa
Reimplement idx and idy to use 16-bit addresses
...
While I have found some conflicting details on how this should be done,
it seems pretty clear to me that IDX and IDY work with 16-bit addresses,
not 8-bit. The inability to do so was preventing us from probing
peripheral ROM (e.g. at $C705, for the disk controller).
2018-01-27 19:54:55 -06:00
Peter Evans
4165c1cefc
Make idx, idy clearer
...
I'm still not confident this is how it _should_ work, but I have found
conflicting accounts online for the behavior of these two modes. The
current code is what allows the Apple II to bootstrap as it should.
2018-01-27 13:04:19 -06:00
Peter Evans
76e4d3797f
By default SLOTCXROM should be high
2018-01-26 22:01:46 -06:00
Peter Evans
ca5276cb6b
It turns out we don't use carry for addr modes.
...
This fix actually corrects a rather irritating bug where the Apple ][
logo was displaying one-off--e.g., as "pple ][D".
2018-01-26 21:18:42 -06:00
Peter Evans
9c0e01ecd2
Add drive phases, switches for control and i/o
2018-01-26 19:49:19 -06:00
Peter Evans
e901bcf54d
Add docblock comments
2018-01-25 14:12:49 -06:00
Peter Evans
217b27b040
Handle inversed text
2018-01-24 20:05:47 -06:00
Peter Evans
2ae272af3a
Stop flickering issue by clearing before drawing
2018-01-24 20:04:53 -06:00
Peter Evans
d581194bbc
Add apple text functions and refactor draw logic for text
2018-01-24 16:11:08 -06:00
Peter Evans
6069ab4d1b
Add inverse font
2018-01-24 14:26:28 -06:00
Peter Evans
cfee8baf25
Refresh once every thirtieth of a second
...
And also refresh on keypress
2018-01-23 23:14:26 -06:00
Peter Evans
882cf2c166
Comment out cycles
2018-01-23 21:41:43 -06:00
Peter Evans
9f518d5141
We should not resolv the address a second time
2018-01-23 21:41:30 -06:00
Peter Evans
1751a7af1f
Don't try to call resolv() if resolv is NULL
2018-01-23 21:18:42 -06:00
Peter Evans
9215600148
Don't attempt to render a glyph if render is NULL
2018-01-23 16:09:27 -06:00
Peter Evans
766aea9c96
Change dbuf switches to work off correct addresses
2018-01-23 15:51:06 -06:00
Peter Evans
8f516db42b
Remove arbitrary counter and allow escape to exit
2018-01-23 15:04:11 -06:00
Peter Evans
775a145480
Rework screen display logic for more efficiency
2018-01-23 14:52:16 -06:00
Peter Evans
b5e1e09a35
Bump up counter by a ton
2018-01-22 21:43:18 -06:00
Peter Evans
b97af6cb16
Disable active refresh
2018-01-22 21:43:01 -06:00
Peter Evans
47d7483297
Disable usleep delay for now
2018-01-22 21:42:42 -06:00
Peter Evans
e0b4fd27e8
Better logging
2018-01-22 21:42:30 -06:00
Peter Evans
56433e2ebe
Show nothing if no value is associated with an instruction
2018-01-22 12:31:19 -06:00
Peter Evans
945bf23f22
Use correct default status and memory mode
2018-01-21 21:33:12 -06:00
Peter Evans
c2debec4d3
Make output more compact
2018-01-21 21:32:43 -06:00
Peter Evans
ef7977c18b
Only set or unset DHIRES if IOUDIS is on
2018-01-21 21:32:22 -06:00
Peter Evans
d119854631
Carry is set by left- or right-most bits
...
Don't rely on modify_status() to get it right.
2018-01-21 16:21:15 -06:00
Peter Evans
3206332a7d
Set carry if the right-most bit is 1
...
Don't consider the left-most bit
2018-01-21 16:17:31 -06:00
Peter Evans
5d8403aaa7
Only set negative if operand has it set
...
That is, don't consider A & operand for negative.
2018-01-21 16:12:03 -06:00
Peter Evans
ecd8a7974a
Add "BAD" instruction to crash when we hit an invalid opcode
2018-01-21 12:48:34 -06:00
Peter Evans
1334e34e76
Use A & oper here
2018-01-21 12:47:58 -06:00
Peter Evans
f9a95827f5
Change carry flag strategy according to docs
2018-01-21 12:47:36 -06:00
Peter Evans
5f93bdae25
Try to match technical behavior described for JSR/RTS
2018-01-21 01:17:04 -06:00
Peter Evans
0581ed6b44
Fix stack in several ways
...
1. The stack should descend, not ascend;
2. The stack should be pushed byte for byte; meaning, when pushing P or
A, those should consume one byte, not two;
3. The MSB should be pushed first when doing JSR and BRK, which makes
some sense if you were reading the stack from $0100 - $01FF.
2018-01-21 01:09:42 -06:00
Peter Evans
42c7fcbb47
XOR the orig and result bit 7 for overflow
...
We should have done this all along. We hadn't accounted for if orig >=
0x80 and result < 0x80, but at that point, it's kind of silly to have a
long complicated condition that we can satisfy simply with an XOR.
(Which is what the machine would do anyway.)
2018-01-21 00:05:49 -06:00
Peter Evans
809e6ca7c6
Overflow should simply be bit 6's value
2018-01-20 23:47:02 -06:00
Peter Evans
fcd25f6385
Use set16 to push items to the stack.
...
The previous method was not incorrect, but set16 already handles the
little-endian logic for us, and there's no need to do something bespoke
here that we then need to test for separately.
2018-01-20 23:43:58 -06:00
Peter Evans
2f777ce881
Several core changes to status, soft switches
...
Regarding soft switches, we had several we should have been listening
for on both reads and writes, but were only doing so on writes; this is
now fixed.
Regarding statuses, we were incorrectly calculating both carry and
overflow. This should now be fixed, although some quick examinations of
disassembly output suggest there is something else amiss. Debugging will
continue shortly.
2018-01-20 21:01:26 -06:00
Peter Evans
103a188faf
Add an extra line break
...
Mostly for vim to make it easier to skip over blocks with '}'.
2018-01-19 19:14:59 -06:00
Peter Evans
a9cf25853d
Show the individual flags of the P register
2018-01-19 13:14:02 -06:00
Peter Evans
6b160c6ca2
Show the dereferenced value for a given address
2018-01-19 12:18:24 -06:00
Peter Evans
2c319399d2
Change disassembly to add more info
2018-01-19 00:34:57 -06:00
Peter Evans
e286ba34f5
Greatly increase counter
2018-01-18 22:19:31 -06:00
Peter Evans
8d9a990997
Remove addresses that aren't handled in dbuf
2018-01-18 22:19:15 -06:00
Peter Evans
0ae4f041e5
Increase counter amount
2018-01-18 16:21:56 -06:00
Peter Evans
d4bf5da480
Draw text in 40 column mode
2018-01-18 16:21:25 -06:00
Peter Evans
a55fd2f71f
Remove log message
2018-01-18 16:20:53 -06:00
