Using ddrhook1, this caused DDR X to crash on startup when the
P3io client sends the currently unknown command 2B. Handling it
with the incorrect p3io command struct, any following reading
attempts from the P3IO by the game fail.
Handle the 2B case explicitly with a generic response that worked
previously before the restructuring of the code. Apply the same
to any further unknown commands with improved logging warning
about this.
Buffers are allowed to have the exact size as the max defined
P3IO buffer size. Cutting it short by one byte causes this
to fail incorrectly when using the pure raw buffer structure
Wrapper/shim library to drive another ddrio in a dedicated
IO thread. Depending on the other ddrio backend used, this
can significantly improve performance while staying
compatible to the existing ddrio API interface
This turned out to be a good solution to solve performance
problems when running MAME with ddrio-p3io that is
(currently) implemented with synchronous IO calls that are
very costly: ~12 ms for a write over the ACIO protocol, ~4 ms
for a read using an IOCTL. As this already adds up to nearly
a full frame (60 fps) regarding latency, there isn't a lot
of time left to do other stuff in a synchronous update loop.
MAME's performance was unstable and dropped all the time below
100%. The result was a choppy gameplay experience.
Combining ddrio-async with ddrio-p3io, the combined backend
is able to drive inputs/outputs at a rate of ~250hz = ~4
updates per frame. This results in an average input latency
of ~4 ms which is as good as it can get with the p3io
hardware's performance limitations that I measured (see
the 4 ms for the IOCTL mentioned above).
This is more than good enough as as update frequency of
the 573 hardware is slightly less than that (I got told
something ~180 hz?).
tl;dr: Gameplay on MAME is great, smooth frame rate, IO feels
amazing and responsive.
By hooking CreateProcessA, we can adjust the commandline to
disable any rotation, which displays the error box at the correct
place on screen (no additional x/y adjustment is needed)
The NVRAM redirection was silently failing because the prop
delete/recreate pair didn't work. This just recreates the entire
config from scratch instead, which guarantees success every time.
By making the NVRAM type "fs", we also make it easier to debug
any issues that people may have.
Initial version that supports the most important
features to operate a DDR SD cabinet with all
inputs and outputs working.
Note that the individual sensor cycling modes are
currently broken. The driver will always set the
sensor read mode to all for now.
With the overhaul of commands, some helpers needed tweaks while
new ones were added to abstract p3io command details with a
common interface, e.g. dealing with the command length field.
Using a real DDR P3IO (Dragon PCB), the overall P3IO command
structures improved significantly. Added further notes about
unknown/unclear commands that were not derivable from the
DDR 18 game binary either.
Note that this module is also used by jubeat to some extend.
The initial design apparently assumed a greater overlap in
commands. This now seems less likely as many commands appear
to be DDR specific.
Refactoring/splitting this is a major effort that is not being
addressed here.
Output the full buffer and the buffer up to the
currently set position. Makes debugging a lot
easier if you know the position set is ok to
only look at the output up to there.
Otherwise, having the full view is also important
to check if data got truncated or checking for
odd looking "garbage" data.
