MIDI-SYNC (was Re: simple MIDI?)

[The Dark force of dance]

Y-ellow Y'all.

At 01:47 PM 1/19/98 +0200, Mikko Helin wrote:

>Even when it's possible to build a discrete MIDI sync out for an
>analog sequencer, it's not much easier to build that decent
>microcontroller sync box. With an Atmel 87C2051 FLASH programmable
>8051 compatible 20-pin uC chip (with UART) it's quite simple to do, and
>when you've done it once, you've learned how to use the same design
>for other purposes (and there are many like MIDI-cv, trigger-MIDI,
>MIDI controller input, DCO etc.). If the 2 kB of FLASH PROM is not
>enough, there are other models with up to 20 kB of FLASH PROM.

This is the thing isn't it. For about 10 bucks you could set it all up with
an ATMEL chip and probably program it to do half a dozen other things as
well. But! The catch for most people is that you have to have some kind of
device programmer. Whilst it's true you can build a pretty simple device
programmer for a 2051, I just had to blow 150 bucks on a little programmer.
Nice little beast it is but you've really gotta get serious with these things.

The problem is that all the iterations of these devices reqire a slightly
diferent programing technique each. Err electrically and protocol speaking
that is. I needed to program 3 devices so I needed a programmer that could
deal with them. However if you're interested, Somewhere I've collected a
circuit that uses 2 or 3 chips and runs off a PC's parallel port. It'll only
program the 89C2051 but that might be all you need.

Of course then you'll need to get all the data on the MCS51 family of micros
and dig in for the learning curve. But it's well worth it in the long run.
There is heaps of code that people have written on the net. A surprising
amount of MIDI related code. There's even 'basic' and 'C' cross-compilers
availble for these little beasts if you so desire it. Everything you need is
on the chip. UART and two counter timers. (3 in the case of the 8xC52) In
fact they range from the little ATMEL chips, which are pretty damn powerful
in their own right, through to one from Seimens which has more perpherals
that you'll probably ever need on a single chip. Not to mention running so
fast that it is equivalent to a standard 8x51 running at 76 meg. All based
on the MCS51 core. All code compatable. And all of the derivatives leave the
original INTEL part in the dust.

Once you're up to speed on the basic MCS51 device, you can pretty much
program all of them.

But if you really get thirsty you might wanna have a taste of the ATMEL AVR
series of RISC microcontrollers. They're pretty damn wicked. Or you might
absolutely drool like Homer Simpson at a doughnut looking at the DEC
Strong-ARM chips. I know I have. Very tasty.

I guess the bottom line is that once you've gone through the pain of
investing in using these devices, they become unbelievebly cost effective.
You get a lot of bang for your buck. You can do a lot of stuff in a very
small space and they cost so little that you can afford to replace boards
full of logic with a couple of little micros. Coupled with the fact that if
you don't like how it works you can reprogram them rather than having to
modify or build new hardware.

Hope this helps.

Be absolutely Icebox.
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