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#1 2009-02-25 15:09:42

Green
Bloody beginner
From: Germany, Marburg
Registered: 2009-02-20
Posts: 6

LEDs for selected Pattern ?

Hi,
is there any possibility to build something that show the selected pattern?
my idea is to build in Leds in the top plastik of the nuberkeys.
all you need is a singnal that send some information about the pattern,
idea cause there is this "pattern select" on User port (H to M) but is it is only input, its no help.

Posible ? in anyway


Commodore:
6x c64c
2x breadbin
Prophet 64
and 3x Gameboy Clasic mit Nanoloop 1.3

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#2 2009-02-27 11:18:01

ron
PROPHET64 GURU
From: berlin
Registered: 2006-07-08
Posts: 502
Website

Re: LEDs for selected Pattern ?

The proper way would be to:
1) find out what RAM address is connected to pattern selection.
2) build some logic circuit that is "listening" to the address bus and demultiplexing the data bits whenever the "pattern select address" gets updated.

How do you do step 1)?
Tricky... Using the prophet/mssiah cartridge, you'd probably need a memory debugging circuit hooked up to the address and data lines. Then, while running the application, watch the bus updating when you select a pattern. Or you 'just' try disassembling the modules from the free edition, or better the krack since memory banks are different in the CE.

edit: VIC video RAM always has the info about which pattern is currently active - find out the bits of the status lights (or "fake LEDs" on the screen sequencer display)?

The dirty way is to ignore the software itself, just adding a demultiplexer to the keyboard matrix so the LEDs simply follow your keystrokes of the number keys 1-8. however a 'stupid' circuit doesn't know which pattern really is selected and therefore it didnĀ“t display anything unless you select a pattern for the first time of a session (so it doesn't show when a saved state is starting with pattern X). as well, I dunno how to treat chains, the demultiplexer could be hooked up to at least light up all LEDs within a chain, but certainly not display what pattern of the chain is playing at the moment ..

Last edited by ron (2009-02-27 11:47:32)

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#3 2009-02-27 11:43:45

ron
PROPHET64 GURU
From: berlin
Registered: 2006-07-08
Posts: 502
Website

Re: LEDs for selected Pattern ?

Or, even simpler: forget about the number keys and use the pattern-select input lines at the user-port instead.

hook up a set of LED-switches (probably to some latch first) and add a multiplex CMOS to form binary values that are fed to the user port pattern selector input lines - and make the software following the "external" pattern select.

According to the "getting started" PDF, there're 5 lines for pattern select (H-M) so I guess three bits are for the patterns (1-8) and 2 bits for bank select (1-4).

However, same thing about the chains as mentioned above - the user port lines don't know what pattern of a chain is the active one. so again, no X0X way of chain play display though..

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#4 2009-02-27 15:42:14

Green
Bloody beginner
From: Germany, Marburg
Registered: 2009-02-20
Posts: 6

Re: LEDs for selected Pattern ?

ok, thanks for thinking about it
i Think the relation of work and value (or how you say it) is to big, and its not that usefull.

smile


Commodore:
6x c64c
2x breadbin
Prophet 64
and 3x Gameboy Clasic mit Nanoloop 1.3

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#5 2009-03-04 14:12:01

R64
Pac-Man
From: Melbourne, Oz
Registered: 2007-01-26
Posts: 222
Website

Re: LEDs for selected Pattern ?

What about using the Midi-sync?

The C64 on only acts as a slave yeah?

I'll shut up if this is a dumb idea smile

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#6 2009-03-05 07:34:39

ron
PROPHET64 GURU
From: berlin
Registered: 2006-07-08
Posts: 502
Website

Re: LEDs for selected Pattern ?

Midi-sync does not know what a slave is doing at all?!?

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#7 2009-03-06 17:37:10

R64
Pac-Man
From: Melbourne, Oz
Registered: 2007-01-26
Posts: 222
Website

Re: LEDs for selected Pattern ?

I was thinking if it was just the timing that you wanted to track then you could have the lights matching the tempo, but yeah you wouldn't know what is selected, so dumb idea confirmed as such!

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