[LAD] midi beat clock

Ralf Mardorf ralf.mardorf at alice-dsl.net
Sat Feb 20 20:59:17 UTC 2010

Gabriel M. Beddingfield wrote:
> On Sat, 20 Feb 2010, Pedro Lopez-Cabanillas wrote:
>>> this "tick" signal (0xf9) must be (is it?) some leftover from ancient
>>> midi times, if ever used effectively. i fail to recognize its use but
>>> being just, uh,... _undesirable_ noise:)
> [snip]
>> 0xf9 is Undefined (Reserved), according to:
>> http://www.midi.org/techspecs/midimessages.php
> [snip]
>> It is an useful site, because the official MIDI specification is not published
>> online my midi.org, but it is not an official source. I would like to know
>> the origin of this "tick" 0xf9 message. Is it an addition from some
>> manufacturer?
> Good point, Pedro.  I think your right, it smalls like a 
> vendor extension.  FWIW, elsewhere on the same site 0xF9 is 
> also marked as unused.
> -gabriel

Probably it was established ex 1989 or 1990?

On midi.org they also say

"Active Sensing. Use of this message is optional. When initially sent, 
the receiver will expect to receive another Active Sensing message each 
300ms (max), or it will be assume that the connection has been 
terminated. At termination, the receiver will turn off all voices and 
return to normal (non- active sensing) operation."

But e.g for this I do have the information, that there isn't the need to 
send active sensing each 300ms. I guess there are unofficial agreements.

I found a side on German. Hehe, for active sensing it differs because of 
my claim, I was a little bit more interpreting, but anyway it also 
differs to midi.org. Because of the topic, MIDI tick on that side is 
included and not undefined, resp. it isn't free for any other usage.


I never had a device understanding MIDI tick, somebody on that list has 
written that he knows a Roland, perhaps Roland is the vendor 
establishing it.

Hm, search engines aren't a help, there is just information about MIDI 
tick, e.g. 
or if e.g. searching for Roland devices, they are talking about "tick" 
for the sequencer resolution, but not because of this.

I never heard of MIDI tick before and I'm nearly sure that there is no 
usual MIDI device from the 80ies were it's implemented.

So if you like to figure out the origin of MIDI tick, you should start 
with research ex 1990 or at the end of the 80ies.

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