The DCI string format uses character values where the high bit of the
last byte differs from the rest of the string. Usually all the high
bits are clear except on the last byte, but SourceGen generally allows
either polarity.
This gets a little uncertain with single-character strings, because
SourceGen can't auto-detect DCI very effectively. A series of bytes
with the high bit set could be a single high-ASCII string or a series
of single-byte DCI strings.
The motivation for allowing them is C64 PETSCII. While ASCII allows
"high ASCII" as an escape hatch, PETSCII doesn't have that option, so
there's no way to mark the data as a character or a string. We still
want to do a bit of screening, but if the user specifies a non-ASCII
character set and the selected bytes have their high bits set, we
want to just treat the whole set as 1-byte DCI.
Some minor adjustments were needed for a couple of validity checks
that expected longer strings.
This adds some short DCI strings in different character sets to the
char-encoding regression tests.
(for issue #102)
Added accelerator keys to Mixed and Null strings. (Issue #67)
Added units to string counts. (Issue #68) Added proper handling
for plural/singular for bytes and strings. Changed N/A indicator
from "xx" to "--".
(1) Added an option to limit the number of bytes per line. This is
handy for things like bitmaps, where you might want to put (say) 3
or 8 bytes per line to reflect the structure.
(2) Added an application setting that determines whether the screen
listing shows Merlin/ACME dense hex (20edfd) or 64tass/cc65 hex bytes
($20,$ed,$fd). Made the setting part of the assembler-driven display
definitions. Updated 64tass+cc65 to use ".byte" as their dense hex
pseudo-op, and to use the updated formatter code. No changes to
regression test output.
(Changes were requested in issue #42.)
Also, added a resize gripper to the bottom-right corner of the main
window. (These seem to have generally fallen out of favor, but I
like having it there.)
Update the symbol lookup in EditInstructionOperand, EditDataOperand,
and GotoBox to correctly deal with non-unique labels.
This is a little awkward because we're doing lookups by name on
a non-unique symbol, and must resolve the ambiguity. In the case of
an instruction operand that refers to an address this is pretty
straightforward. For partial bytes (LDA #>:foo) or data directives
(.DD1 :foo) we have to take a guess. We can probably make a more
informed guess than we currently are, e.g. the LDA case could find
the label that minimizes the adjustment, but I don't want to sink a
lot of time into this until I'm sure it'll be useful.
Data operands with multiple regions are something of a challenge,
but I'm not sure specifying a single symbol for multiple locations
is important.
The "goto" box just finds the match that's closest to the selection.
Unlike "find", it always grabs the closest, not the next one forward.
(Not sure if this is useful or confusing.)
Sometimes there's a bunch of junk in the binary that isn't used for
anything. Often it's there to make things line up at the start of
a page boundary.
This adds a ".junk" directive that tells the disassembler that it
can safely disregard the contents of a region. If the region ends
on a power-of-two boundary, an alignment value can be specified.
The assembly source generators will output an alignment directive
when possible, a .fill directive when appropriate, and a .dense
directive when all else fails. Because we're required to regenerate
the original data file, it's not always possible to avoid generating
a hex dump.
Changing an ASCII character operand back to default was going
through a path that tried to resolve low vs. high ASCII, which
isn't useful when you're removing the item. The root of the problem
was that the "default" button wasn't properly resetting the UI.
Also, updated keyboard shortcuts to be in sync with the instruction
operand editor.
I didn't think it made sense, but I found something that used it,
so apparently it's a thing. This updates the operand editor to
let you choose PETSCII+DCI, and updates the assemblers to handle
it correctly (really just 64tass, since the others either don't
have a DCI directive or don't deal with PETSCII at all).
Changed the char-encoding sample from "bad dcI" to "pet dcI", and
updated the documentation.
Both dialogs got a couple extra radio buttons for selection of
single character operands. The data operand editor got a combo box
that lets you specify how it scans for viable strings.
Various string scanning methods were made more generic. This got a
little strange with auto-detection of low/high ASCII, but that was
mostly a matter of keeping the previous code around as a special
case.
Made C64 Screen Code DCI strings a thing that works.
The previous code output a character in single-quotes if it was
standard ASCII, double-quotes if high ASCII, or hex if it was neither
of those. If a flag was set, high ASCII would also be output as
hex.
The new system takes the character value and an encoding identifier.
The identifier selects the character converter and delimiter
pattern, and puts the two together to generate the operand.
While doing this I realized that I could trivially support high
ASCII character arguments in all assemblers by setting the delimiter
pattern to "'#' | $80".
In FormatDescriptor, I had previously renamed the "Ascii" sub-type
"LowAscii" so it wouldn't be confused, but I dislike filling the
project file with "LowAscii" when "Ascii" is more accurate and less
confusing. So I switched it back, and we now check the project
file version number when deciding what to do with an ASCII item.
The CharEncoding tests/converters were also renamed.
Moved the default delimiter patterns to the string table.
Widened the delimiter pattern input fields slightly. Added a read-
only TextBox with assorted non-typewriter quotes and things so
people have something to copy text from.
We've been treating ASCII strings and instruction/data operands as
ambiguous, resolving low vs. high when generating output for the
display or assembler. This change splits it into two separate
formats, simplifying output generation.
The UI will continue to treat low/high ASCII as as single thing,
selecting the format appropriately based on the data. There's no
reason to have two radio buttons that are never both enabled.
The data operand string functions need some additional work, but
that overlaps substantially with the upcoming PETSCII changes, so
for now all strings set by the data operand editor are low ASCII.
The file format has changed again, but since there hasn't been a
release since the previous change, I'm leaving the file format
at v2. Code has been added to resolve the ASCII mode when loading
a v1 project file.
This removes some complexity from the assembly code generators.
We used to use type="String", with the sub-type indicating whether
the string was null-terminated, prefixed with a length, or whatever.
This didn't leave much room for specifying a character encoding,
which is orthogonal to the sub-type.
What we actually want is to have the type specify the string type,
and then have the sub-type determine the character encoding. These
sub-types can also be used with the Numeric type to specify the
encoding of character operands.
This change updates the enum definitions and the various bits of
code that use them, but does not add any code for working with
non-ASCII character encodings.
The project file version number was incremented to 2, since the new
FormatDescriptor serialization is mildly incompatible with the old.
(Won't explode, but it'll post a complaint and ignore the stuff
it doesn't recognize.)
While I was at it, I finished removing DciReverse. It's still part
of the 2005-string-types regression test, which currently fails
because the generated source doesn't match.
