LPC17 based Core - how many DIN, DOUT, AIN

Design Concepts
1

Hi,

after a long time I’m finally back here as I plan to start converting my former organ conversion into something even more advanced.

What I would like to do is replace the current MIDI-USB-soundcard built into my organ and the current MIDI interface with one single LPC17 based core.This MIDI-USB-soundcard is merging the MIDI output of the legacy PIC core and the built-in BOEHM MIDI controller that controls the manuals and pedal into one single MIDI data output.

This would mean that all manuals (61 keys upper, 61 keys lower, 30 keys pedal), approx. 100 push buttons, approx. 60 drawbars and analogue turning knobs would have to be controlled by the LPC17 based core, and it should also keep the legacy LCD panel currently connected to the PIC core.

The program to do that could be rather simple as I do not plan to implement much of dynamic parameter switching, but nevertheless particularly controlling the manuals and pedal has to be really fast so there would not be much delay.

Not only would the LPC17 core simplify the overall hardware design, but it would also enable me to eliminate the need for the soundcard merging the MIDI data streams.

I wonder if the LPC17 core is fast enough to do that?

Where can I find circuit sheets to connect the manuals in a matrix like way, or can I connect the manuals in the same way as I would connect the push buttons?

If one dares - is it really possible to run 64 AIN ports together with 128 DIN ports and approx. 1000 matrix scan buttons?

Why does the MIDIIO128 application for the LPC17 core only allow for 8 AIN ports? Is this a limitation of the software for this application, or is the hardware limited somehow?

Maybe someone here has already done such a complex conversion and can add some hints for me?

Thanks for all howtos and hints in advance, many regards and happy new year to all of you,

Crypto.

2

Of course, the LPC17 core has enough resources to handle this! :slight_smile:

Due to the USB MIDI port it especially provides the required bandwidth (more than 100 times faster) to transfer so many MIDI events concurrently.

Where can I find circuit sheets to connect the manuals in a matrix like way, or can I connect the manuals in the same way as I would connect the push buttons?

Schematic: see the MIDIO128 page, keyword “Scan Matrices”

The push buttons should be connected as matrices as well to avoid unnecessary cabling and to reduce the number of DIN modules.

Why does the MIDIIO128 application for the LPC17 core only allow for 8 AIN ports? Is this a limitation of the software for this application, or is the hardware limited somehow?

Yes and no.

http://discourse.midibox.org/t/topic/16088

Multiple MBHP_AINSER64 modules can be cascaded, also the wiring will be much easier since the modules are connected via a single ribbon cable to the core.

Btw.: I’m still searching for people who are interested to join the prototype order for this PCB.

The prototypes will be a bit more expensive than later in SmashTVs shop (I guess ca. 10 EUR per PCB), but you would help me to finance this (sparetime) development.

Best Regards, Thorsten.