Merge 8b22ef1e8c into sapling-pr-archive-icex2

doc/iidxhook/README.md

@@ -48,6 +48,8 @@ Available implementations that can be swapped out depending on which kind of IO
 use:
 
 - `iidxio`: Default implementation supporting keyboard, mouse and USB game controllers
+- [iidxio-async](iidxhook/iidxio-async.md): Shim implementation that runs another iidxio implementation in a dedicated
+  thread
 - [iidxio-bio2](iidxhook/iidxio-bio2.md): Support BIO2 hardware
 - [iidxio-ezusb](iidxhook/iidxio-ezusb.md): Support C02 ezusb FX hardware
 - [iidxio-ezusb2](iidxhook/iidxio-ezusb2.md): Support IO2 ezusb FX2 hardware

doc/iidxhook/iidxio-async.md

@@ -0,0 +1,22 @@
+# IIDXIO async API implementation
+
+This implementation of the iidxio API is a shim library that takes another iidxio library and
+runs the functions `iidx_io_ep1_send`, `iidx_io_ep2_recv` and `iidx_io_ep3_write_16seg` in a
+dedicated thread. State synchronization to the getter and setter functions is also handled
+transparently.
+
+Usage of this **may** improve performance of certain iidxio implementations or when using them
+in certain integrations, e.g. the send and receive functions of a iidxio implementation for some
+target IO hardware calls are synchronous and expensive. 
+
+This is not a fix/solution to a badly implemented iidxio library with poor performance as it cannot
+make it go faster and address potential latency issues, for example.
+
+Use with caution and know why and when you need to use it.
+
+## Setup
+
+* Add `iidxio-async.dll` in the same folder as your `iidxhookX.dll`
+* Rename your `iidxio.dll` to `iidxio-async-child.dll`
+* Rename `iidxio-async.dll` to `iidxio.dll`
+* Run the game