Analogue-sequencer

Colin, on your website you mention that in the development versions
you had the interface hardware connected to a BBC Micro - is there any
chance of a bit more info on how and what you actually did here?

Thanks

--- In analogue-sequencer@yahoogroups.com, "mayday_xl" <yahoo@c...> 
wrote:
> Colin, on your website you mention that in the development versions
> you had the interface hardware connected to a BBC Micro - is there 
any
> chance of a bit more info on how and what you actually did here?

I don`t know if you`re familiar with the BBC micro, but it had very 
good interfacing capabilities, including a 1MHz bus which provided 8 
bit data and address busses for accessing external peripherals.
The P1 hardware was just a 6850 based midi interface, and 8 channels 
of CV and gate output attached to a BBC via the 1MHz bus. The 
sequencer software only drove synths via cv and gate - the midi 
interface was purely for sync, and the user interface was 
keyboard/VDU based. This hardware later evolved into a stand-alone 
midi to cv convertor with a dedicated 6502 CPU board. That was a 
long time ago - around `91 IIRC.
P2 was much closer to the current P3 hardware, with all the knobs, 
switches and so on, but still attached to a BBC.
If you look at the schematic for the main board of the P3 you`ll see 
that the user interface hardware is all connected to a separate bus 
from the main memory, that has an address decoder to select the 
various devices that drive the interface.
P2 was essentially just the electronics attached to this bus via the 
BBC micros 1MHz bus. The conversion to a stand-alone unit involved 
building a separate 8051 based CPU board which had an interface 
similar to the BBC 1MHz bus which connected to the P2 user interface 
hardware by a ribbon cable. After the prototype stage, all the logic 
moved onto a single board. In the process of being converted from a 
6502 processor driving the hardware to the 8051, it became P3. Since 
then, the hardware hasn`t changed much - just the extra support for 
the mode switches and LEDs.

Cheers,
Colin f

...currently waiting for a taxi to Cancun airport to get the 10 hour 
flight home :-(

--- In analogue-sequencer@yahoogroups.com, "colinfraser_com"
<colin@c...> wrote:
> --- In analogue-sequencer@yahoogroups.com, "mayday_xl" <yahoo@c...> 
> wrote:
> > Colin, on your website you mention that in the development versions
> > you had the interface hardware connected to a BBC Micro - is there 
> any
> > chance of a bit more info on how and what you actually did here?
> 
> I don`t know if you`re familiar with the BBC micro, but it had very 
> good interfacing capabilities, including a 1MHz bus which provided 8 
> bit data and address busses for accessing external peripherals.
> The P1 hardware was just a 6850 based midi interface, and 8 channels 
> of CV and gate output attached to a BBC via the 1MHz bus. 

[....]

> 
> Cheers,
> Colin f
> 
> ...currently waiting for a taxi to Cancun airport to get the 10 hour 
> flight home :-(


That's great, thanks - you could have waited until you got home, but I
guess writing an essay about the BBC micro is a better way than some
of killing time at an airport ;). Thanks again.