Daisy Seed Interfacing with 74HC165 and 74HC595A over SPI

Hardware Development
1

Hi all!
I’m looking for tips on how to approach this project.
I’ve got a Moog Mother 32 with a bad DSP IC. I did remove it because I had issues with the 3V3 rails and it solved the problem.
I tried to get a new IC from Moog but was not possible.
That gave me an idea, to clone the behaviour of the digital part of the synth using the existing hardware.
All the analog part works, in fact, I can use it with external hardware, I modded it so the EG could receive external gates. Originally the EG is processed by the DSP IC so it can generate a gate or a trigger if the sustain is on or off.

I can receive MIDI from the circuit of the Moog into the Daisy Seed, but I need to test if I can read the buttons on the board and light up the LEDs.
All the bottons, originally, are conected to the DSP, by three 74HC165 (8-bit shift register) cascaded and the LEDs are controlled by three 74HC595A (8-bit shift register with latched 3 state output).
So my question is, how should I read and write to this chips using plugdata and hvcc?

Also I’m a little confused by the way Daisy Seed pins are addressed in plugdata, I can’t get a blink patch to work with plugdata but MIDI In is no problem. So my problem is how send the information to the pins.
Do you think plugdata is the right approach for this task?

Thanks!

2

What is it that you want the Seed to do in this project exactly?

These SPI chips are anyway not supported by libDaisy, so they will also not work with heavy/plugdata.

3

Thanks for your quick response.

To clarify, those chips are not supported or libDaisy does not support any SPI, therefore there’s no support in plugdata?

What I want to do is to first be able to use the existing hardware with the Daisy Seed, read the button press and be able to light the LEDs.

Then, ideally, use the keyboard and build a sequencer like the one in the original.

4

As I said: these chips are not supported by libDaisy. Heavy relies on libDaisy to use hardware integrations.

You can find some pd topics in this subforum: Pure Data - Daisy Forums

Also read Board JSON - Heavy Compiler Collection

5

Oh! Ok. I thought that SPI was a standard therefore supported by libDaisy since there’s a How to use the SPI on the libDaisy site.

So there goes my project hahahaha.

Just curious, why is that chip not supported?

Thanks for your time anyways.

Best Regards!

6

I never said that SPI outright doesn’t work, this is just a communication bus. What I said is that these specific chips are not supported (yet) in libDaisy. The library needs to decode the communication to/from these ICs.

You can see some of the supported ICs here: libDaisy/src/dev at master · electro-smith/libDaisy · GitHub