On Jan 28, 2017 22:20, Ralf Mardorf <ralf.mardorf@xxxxxxxxxxxxx> wrote: > > On Sun, 29 Jan 2017 09:14:07 +0100, Ralf Mardorf wrote: > >On Sat, 28 Jan 2017 17:55:40 -1000, david wrote: > >>So I wonder. Is there some sort of upper speed limit in the MIDI > >>standard? Is the MIDI standard smart enough to negotiate speeds if > >>various MIDI devices differ? Or was the MIDI standard strict in > >>saying that your device must operate at this official speed? > > > >You are aware that MIDI data simply is send and received without a time > >stamp and without any sync. The software checks if an ACIA/UART > ^^^^^^^^^^^^^^^^ English isn't my native language, this > phrase might not be that good, but it anyway is to the point. > > >register reports that a byte was received by a short machine language > >endless loop. The endless loop is only interrupted by a branch, if a > >byte was received, to read the byte and then to continue the endless > >loop. On old computers such as the C64 a lot of MIDI operations were > >done by even disabling IRQs. The 65xx chips have a command to disable > >timer and break command/flag IRQs, named SEI. One MIDI interface must > >use the same rate on both ends, the receiver and transmitter, but if > >you use different interfaces you could ignore the MIDI standard and > >chose any other rate, as long as sender and receiver chose the same > >rate. IOW one interface could not communicate with several MIDI > >interfaces using different rates. Sorry, all I know about MIDI is how to connect cables, channels, program banks, patch sets. I have a vague idea that old-style MIDI cables had a max data rate comparable to telephone line modems. Used to program on a C64. I wrote a Mandelbrot set generator in 6510 assembler. Had to turn off interrupts to get processing time down to many many hours vs the days it took in BASIC. Fun times. David W. Jones gnome@xxxxxxxxxxxxx authenticity, honesty, community http://dancingtreefrog.com _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user
