On Monday 19 June 2006 22:53, Ron D'Eau Claire wrote: > As far as I know, there is NO such thing as a "RS232 cable".
My several Amigas have a 25 pin 'serial' port. There is also +/- 9v AC on a couple of pins to power external equipment. It's welcome: I designed my own midi interface using +9 AC to power it. An important point about RS-232, COM ports, /dev/cuad0, /dev/ttyS0 .. whatever, is that the serial data timing can be very accurately known: the time taken for a micro to load to the data registers and send the data can be used in real time control. At 115200 bits per second, a byte takes less than 100 microseconds to propagate. Midi is such a real time control and it uses the very modest speed, by today's standard, 31250 bps. USB can't guarantee such timing accuracy for control purposes - witness the mess with USB midi equipment that had 80 milliseconds delay before hearing a sound - fine if a printer doesn't start in that time but completely useless for real time music multitracking. A klutz was required, such as Steinberg's ASIO. Even so, USB still can't compete with a 23 year old standard at 31250 bps for real time midi. There is no USB on my Kurzweil PC2R. Present are midi in, out and thru, analog and 24 bit digital sound out: it's professional equipment. There's nothing wrong with Serial except that most consumers don't need it, and unfortunately, those who could use it are finding it scarce on modern equipment due to market forces. Ian, G4ICV, AB2GR, K2 #4962 -- _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
