[sdiy] Great weekend in Cambridge

[Colin f]

> The Cirklon , nice name btw, looks groovy, nice '909' switches ! 
> Where can I order those if you don't mind sharing Colin ?

The switches are Cherry MX. I think the keycaps are also a Cherry part,
though they may be from a third party.
I get them from these guys:
http://www.apc-plc.co.uk/pagebuilder.asp?Id=469
but you might find them locally if you google for them.
The switch bodies take a 3mm LED, you can fit whatever colours you like.

> I have the 
> 909 programmer on the bench on the original NEC which I've 
> painstakingly disassembled and it would be nice to finish that part 
> of the design with some 909 ish switches, even bought the square 
> punch off a guy on ebay thats almost perfect for the original 
> switches....

You may be better to get the actual 909 switches - Technology Transplant
remake the original step and tact switches.
 
> Which micro or dev board would you suggest if you had to recommend 
> one for these types of musical applications , i.e. sequencers, 
> arpegiators... I have yet to move from 8051 based stuff mostly 
> because my dev board has been a modified Alesis MMT8 nad Eprom 
> Emulator for years and haven't found anything as much fun since what 
> with the Hitachi  2 x16 LCD, MIDI, 64 K of SRAM, and all those 
> buttons and leds....Are you using ST ARm micros in the Circlon ?

I'm using the high-density ST Cortex-M3 part.
It is a huge step up in power from an 8051, and also in ease of development.
I'm using the STM3210E-EVAL board. It has 140 pins on 2 headers to connect a
daughterboard, and you get every single CPU connection you might need on
there.
There are a couple of limitations with it, for example, you cant use UART5
and the SD-Card interface at the same time, but I figured 4 independent MIDI
ports is probably enough.
It takes a bit more effort to get started on the Cortex, mainly because the
sheer number of peripherals and corresponding configuration and control
registers is huge.
But it's worth it for the power ;-)

Cheers,
Colin f