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738 Commits

Author SHA1 Message Date
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 
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 
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 
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 
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 
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 
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 
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 
Also, there's no need for a while statement; we can just reset to zero.
 2018-02-14 22:09:21 -06:00
Peter Evans 7224698cd7 This should be EOR, not ADC 
I might as well fix the bad opcode here, too!
 2018-02-14 21:50:13 -06:00
Peter Evans 9a5c94bbbb The 49 opcode is EOR, not ADC. 
Excuse me, I just need to scream now.

AHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH
HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH
HHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH

Thank you for your indulgence. Please carry on.
 2018-02-14 21:37:02 -06:00
Peter Evans 64b9cbefcb Several changes to phase and writes 
1. The phaser algorithm was reworked, and it should be more accurate in
choosing when to step forward or backward.
2. Writes should be committed when the latch has bit 7 high. This hasn't
actually been a problem yet, since other things are broken! But we might
as well fix it now that we've seen it.
 2018-02-14 16:49:20 -06:00
Peter Evans 100621a6c6 Show second-digit row mappings for gcr62 2018-02-12 21:20:09 -06:00
Peter Evans 5b1298bded Document the gcr62 table 2018-02-12 21:19:47 -06:00
Peter Evans ec522f259e Add block comments to describe source files 2018-02-12 21:15:20 -06:00
Peter Evans 0822b2f4ba Use the correct file name 2018-02-12 21:11:50 -06:00
Peter Evans 5c0f65215b Use the correct file name 2018-02-12 20:18:17 -06:00
Peter Evans 1e3f2e5781 Use the correct name of the source file 2018-02-12 19:28:37 -06:00
Peter Evans e63d7e5d72 The file is apple2.dd.c 2018-02-12 18:24:35 -06:00
Peter Evans 9e26e215cd In which we discover that image doesn't matter 2018-02-11 20:38:51 -06:00
Peter Evans ba387c004f We should be dividing, not using modulus 2018-02-11 20:36:41 -06:00
Peter Evans 3e2d8acacf The same track/sector method works for all images 
Particularly so as the data segment is now the 6-and-2 encoded form,
which we either encode from DOS 3.3/ProDOS, or use literally from NIB
files.
 2018-02-11 20:25:44 -06:00
Peter Evans 4765dab912 Don't run erc after building it 2018-02-11 19:28:26 -06:00
Peter Evans 350a06890a Split up logic for keyboard test 
In accordance with the split in logic we had made for the source
function
 2018-02-10 18:31:38 -06:00
Peter Evans 69d425db2d Add tests for vm_di 2018-02-10 18:25:29 -06:00
Peter Evans 919869289e Add missing test for reflect functions, init 2018-02-10 18:20:50 -06:00
Peter Evans 9f60e61cfb Add missing docblock comments 2018-02-09 23:14:05 -06:00