Peter Evans
a614c1e5df
Add new file, vm_debug.c, and help command for it
2018-02-23 21:58:30 -06:00
Peter Evans
ac5d532a7f
Fix length bug with s_bytes (one too short)
...
This also fixes tests for disassembly so that they account for changed
output. Finally this also exits if we have to perror in the setup
function.
2018-02-23 21:35:53 -06:00
Peter Evans
395ac4a841
Disassembler now outputs more idiomatic code
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It also no longer prints out register and address state
2018-02-23 20:46:24 -06:00
Peter Evans
0d1e22a348
Add support for decimal mode ADC/SBC.
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This also corrects a bug where SBC set carry incorrectly in binary mode.
2018-02-23 00:46:07 -06:00
Peter Evans
2669460c6d
Resolve potential bad dereference on sectab
2018-02-22 14:11:54 -06:00
Peter Evans
bee2a0e86a
Add missing docblocks for NP2 and NP3
2018-02-22 14:10:19 -06:00
Peter Evans
978ad1faaf
Formerly "BAD" instructions are now forms of NOPs
...
But weird forms. In most cases they basically are NOPs, except with
different opcodes. In other cases, we call them NP2 and NP3s, and do so
because they consume 2 or 3 bytes respectively (vs. just 1 with NOP).
We had to teach some arcane magic to the emulator for this to work. We
may want to refactor to decouple the number of bytes consumed from the
address mode.
2018-02-22 14:07:05 -06:00
Peter Evans
691387894a
ASL, LSR, ROL, ROR in ABX now consume only 6 cycles
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(Down from 7 cycles.)
2018-02-22 13:45:36 -06:00
Peter Evans
e35ff91fa7
Clear the decimal bit in BRK; also improve test logic for BRK
2018-02-22 13:44:13 -06:00
Peter Evans
90892c32e4
Add TSB (Test and Set Bits) instruction
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This commit also moves the TRB code from loadstor to bits, which is
where it should have been all along.
2018-02-22 13:39:48 -06:00
Peter Evans
a4c3d1c4ef
Implement the TRB (Test and Reset Bits) instruction
2018-02-22 00:39:33 -06:00
Peter Evans
807362e871
Add STZ instruction (to store zero)
2018-02-22 00:02:57 -06:00
Peter Evans
7363547608
Add PHX/Y and PLX/Y to the opcode, addr mode, cycle tables
2018-02-21 23:35:36 -06:00
Peter Evans
8e1ab0e950
Add support for PHX, PHY, PLX, PLY
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These instructions allow you to push and pull (pop) the X and Y
registers via the stack.
2018-02-21 23:32:57 -06:00
Peter Evans
f9a277e7bc
Add new Branch Always instruction
2018-02-21 21:57:21 -06:00
Peter Evans
58a1e31f58
Allow JMP to work with ABX address mode
2018-02-21 21:46:41 -06:00
Peter Evans
8623945bbf
Add the ability to INC or DEC the accumulator
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This is an oversight from the 6502 processor that was rectified in the
65c02 model.
2018-02-21 21:20:05 -06:00
Peter Evans
7b65dc1657
Add new BIM instruction (BIt imMediate mode)
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This is not a real instruction in the 65c02 processor; I invented it for
the sole purpose of handling the specialized logic that is performed by
BIT in IMM mode. To be fair--I can imagine this really _was_ implemented
as a "separate" instruction on the chip! But I don't know that for sure.
2018-02-21 21:01:46 -06:00
Peter Evans
5ba5f91442
Add new address modes for BIT
2018-02-21 20:46:28 -06:00
Peter Evans
e1f11fc266
Add cycle counts
2018-02-21 20:43:04 -06:00
Peter Evans
739451366f
Add zero-page instructions
2018-02-21 20:42:05 -06:00
Peter Evans
48872cf8d1
Add docblock comment for apple2_dd_sector_num
2018-02-21 11:23:25 -06:00
Peter Evans
61eb880f49
Refactor code to pass image type in
2018-02-21 00:23:12 -06:00
Peter Evans
8706a81d1f
Remove spurious printf
2018-02-20 15:55:40 -06:00
Peter Evans
1091ec6e2a
Pass image type into enc_dos; use sector_num instead of a table pointer
2018-02-20 15:36:23 -06:00
Peter Evans
c2e90651ac
Again, latch data must be > 128 (0x80)
2018-02-20 14:44:17 -06:00
Peter Evans
e826fc05d9
We can only write latch data that is > 128
2018-02-20 14:43:33 -06:00
Peter Evans
98f640f0d1
Use the proper sector header length (20 bytes)
2018-02-20 14:35:07 -06:00
Peter Evans
08f3899de4
Tracks don't move from shifting; sector work
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The sector work being:
- We only wrap around if we go beyond the length of an encoded track, so
use ENC_ETRACK.
- If we DO wrap around, we don't use modulus; we simply reset to zero.
2018-02-20 14:33:36 -06:00
Peter Evans
c7fbb4aa50
Backward steps require adjacent phases
2018-02-20 14:30:20 -06:00
Peter Evans
28061c1d11
Adjust length/data for sectors; cleanup some magic numbers
2018-02-20 01:00:46 -06:00
Peter Evans
2318b1917a
This form needs two RORs to work
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That's because the first ROR pushes the 1 in bit0 into the carry bit;
the second moves the carry bit into the bit7 position, which will match
128.
2018-02-19 22:01:30 -06:00
Peter Evans
d590a809d8
Tests should reflect how carry is handled in ROL/R now
2018-02-19 21:59:55 -06:00
Peter Evans
65f13bb1e4
Add missing output and fix buffer size issue
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We use BUFSIZ everywhere, except in setvbuf(), which kinda needs to know
the proper buffer size. Because we were passing 256, which is (much!)
lower than BUFSIZ, we were wrapping output around in an odd, unexpected
way.
2018-02-19 21:49:58 -06:00
Peter Evans
9f0d7f5413
Fix some compile failures due to changed params
2018-02-19 20:03:25 -06:00
Peter Evans
508be6458a
Pass in sector table for logical-physical orders
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We were not encoding data properly, because in DOS 3.3 and ProDOS,
sectors must be interleaved on disk media (whereas in the original image
form, data is laid out in a linear fashion).
This solves a bug where we erroneously encountered a "bad" opcode (a7)
in the program code.
2018-02-19 18:49:37 -06:00
Peter Evans
3ab654c306
Correct note on GBASL/H address
2018-02-19 13:53:48 -06:00
Peter Evans
96e4b5d9d8
Remove JSR WAIT to speed up disk II controller
2018-02-19 00:48:11 -06:00
Peter Evans
015104bd57
Self-sync bytes should be written after a sector header
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Not after the data field marker, where the controller/RWTS don't expect
to find them.
2018-02-18 23:46:48 -06:00
Peter Evans
c89e855559
Update to use correct encoded sector length
2018-02-18 23:46:18 -06:00
Peter Evans
00854e74b9
Explain how the JSR call is handled in some impls
2018-02-18 19:49:34 -06:00
Peter Evans
0fccf552f2
Final comments
2018-02-18 11:16:09 -06:00
Peter Evans
7c2c6d5d54
Reformat and annotate disk II controller code
2018-02-18 00:50:50 -06:00
Peter Evans
0d1e949d13
Mask the result so it's never more than a byte
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This is because the eff_addr variable is a 16bit one, and adding addr +
X or addr + Y can possibly result in a 9-bit value, which is not what we
want. (You'd be pulling data from the stack instead of the zero page.)
2018-02-16 00:44:55 -06:00
Peter Evans
e9164d9872
Very minor changes to make the code simpler
2018-02-16 00:19:14 -06:00
Peter Evans
058b45e7d1
Use 9-bit rotation, not 8-bit
2018-02-15 19:32:01 -06:00
Peter Evans
067c0cea2f
Also check the N flag (i.e. set it to zero)
2018-02-15 13:01:58 -06:00
Peter Evans
e415b3e490
We should check only the first byte for zero
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We need to accept values for result that are greater than a byte so that
we can determine if carry is set, but this causes an issue when an app
uses addition to force an overflow that would set the zero bit. Masking
result for only the LSB fixes that problem.
2018-02-15 00:26:21 -06:00
Peter Evans
08b0e2e648
Show effective address
2018-02-14 22:19:35 -06:00
Peter Evans
fe70cd1f71
Remove debugging, use ENC_ETRACK for sector pos max
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Also, there's no need for a while statement; we can just reset to zero.
2018-02-14 22:09:21 -06:00
