MIDI to trig revisited.

[Stewart Pye]

Hi...

Some of you will remember my midi to drum trigger project using an R2R DAC
and multiplexer to achieve velocity controlled pulses. Anyhow, I'm making
some major design changes as a result of discovering a cool chip....

TLC5628CN 8 channel 8bit serial input DAC. 
It is controlled via a 3 wire interface from the micro and can handle high
speed.(the full bit rate of a PIC at 8Mhz) So, It will take less than 5uS
from the time you have have the velocity byte to the time it's output.
Plenty fast enough. And....

No need for analog mux
No need for sample/hold
Runs from +5v supply
Has 8 voltage outputs.
The range is set to X1 or X2 with one of the 12 serial control bits. (And 3
for address, 8 for data)
Ties up less pins on the micro

Hope this wasn't too OT. I just had to tell somebody. I've come accross
some cheap backlit LED displays too so I think I'll do a deluxe model with
LCD, 2 DAC's for 16 outputs and 3 or 4 switches for setup with the LCD.
This will enable it to be used for midi controllers or drum triggers.(If
the 16F84 can handle all that. I think it's time to take the plunge to AVR).

Sorry for Rambling :-)

Stewart.