beep | little package that brings sound | Audio Utils library

Playing a single tone with PC speaker may use method mentioned in the quoted question. It uses square-wave generator from system timer, activated by setting mode of operation 0xB6 to I/O port 0x43. See Timer Ports. The value 182=0xB6=0y10110110 written to port 0x43 specifies

• selection of timer counter Nr.2 (bits 6-7)
• endianess: LowByte first, HighByte second (bits 4-5)
• mode 3: square-ware generation (bits 1-3)
• format 0: binary mode (bit 0). Then you are expected to specify the required frequency with OUT 0x42,LowByte and OUT 0x42,HighByte. This 16bit binary integer number actually specifies period of the square wave, i.e. the number of ticks that must elapse to flip the wave from 0 to 1 and vice versa.

When you have programmed the frequency, ask the Programmable Peripheral Interface to connect speaker to the square-wave generator. This is done by setting the two least significat bits if PPI port 0x61, see PPI Ports.

Try this for quicker row deletion:

This function takes an input file, extracts the R code in it according to a list of patterns, evaluates the code and writes the output in another file.

So the thing you are observing is due to the fact all R code in the .rmd gets evaluated before the whole process is finished. The sound plays when the beepr line is executed, since this will happen (rcode chunk) before the document is processed by pandoc (or similar) i would just advise you to put the beeper outside of the .rmd itself to trigger it after the process finished. write a 3 line r sript:

Float literals in Delphi are Extended by default. In 64 bits, that shouldn't make any difference, but in 32 bits it does. My guess is that the parser still internally represents float literals as a 10 byte float(extended), and then the 64 bits compiler "round it down" to 8 bytes(double) when compiling.

If my hypothesis is right, there might be nothing that can be done to circumvent that.

EDIT

Delphi does the following conversion

• Double(3FE56C4FB47339B3) converts to Extended(3FFEAB627DA399CD9800)
• Double(3FE56C4FB47339B4) converts to Extended(3FFEAB627DA399CDA000)
• 0.6694716 is Extended(3FFEAB627DA399CD9C00)

This is how the plot of Fourier_x alone looks like:

found some answers to my own question, sharing with community

6-sec auto-switch mode is a new feature in Android 12, which works only if (mode == AudioSystem.MODE_IN_COMMUNICATION) (check out flow related to MSG_CHECK_MODE_FOR_UID flag). This should help for MODE_IN_COMMUNICATION set to AudioManager and left after app exit, this was messing with global/system-level audio routing. There is also a brand new AudioManager.OnModeChangedListener called when mode is (auto-)changing

and setSpeakerphoneOn turns out to be deprecated, even if this isn't marked in doc... we have new method setCommunicationDevice(AudioDeviceInfo) and in its description we have info about startBluetoothSco(), stopBluetoothSco() and setSpeakerphoneOn(boolean) deprecation. I'm using all three methods and now on Android 12 I'm iterating through getAvailableCommunicationDevices(), comparing type of every item and if desired type found I'm calling setCommunicationDevice(targetAudioDeviceInfo). I'm NOT switching audio mode at all now, staying on MODE_NORMAL. All my streams are AudioManager.STREAM_VOICE_CALL type (where applicable)

for built-in earpiece audio playback aka. "ear-friendly mode" we were using

You want the play_audio function to be called every 60/bpm seconds, but the function call itself takes time: you need to read the file, open the stream, play the file (who knows how long it is) and close the stream. So that adds to the time from one click to the next.

To fix this problem, you could try subtracting the time it takes to run the play_audio function from the time you sleep. You could also experiment with running play_audio on a separate thread.

So, I solved the issue with the async / promise.

The C++ code is sending the file size before sending the file data (good), but is not doing adequate error handling (bad), and it is NOT sending the file size in an platform-agnostic format (bad).

Not that it matters, because the Java code shown is NOT even attempting to read the file size before reading the file data (very bad), nor is it paying attention to the return value of in.read() to know how many bytes are actually received. But even if it were, the C++ code is sending the size as an 8-byte integer (needed for large files > 2GB), but the Java code is using a 4-byte integer instead (bad). The C++ is also using a 4-byte integer for bytes_sent in SendFile().

Try something more like this: