Hello and thanks for some help here. I am completely new to Arduino but a retired SuperCollider user so I can make "some" sense of the code. However, what I am trying to do is probably so simple I can' t really find any examples. Plus, I have no desire to do anything else with Arduino and just have been bogged down for days digging through docs, examples, etc. but there is so much and it is so spread out that I really hope one of you master users can easily alter this code so I can make music:) I have 8 NeoTrellis boards in a grid, running through a Teensy 4.0. I am using the code below and need to figure out how to: a: send MIDI noteOn/noteOff messages from each button (SuperCollider sees it as a MIDI device but no information comes through). b: change the colors for specific buttons (i.e. - button 1 is red, button 5 is green, etc.) AND I would like the buttons to be already lit with less brightness and then when selected the brightness doubles. I hope that makes sense. I have had success registering the board, changing colors with some of the example code posted below but also have a hard time tracking down what certain objects/classes do! I also tried to monitor it in the Serial Monitor but got nothing in response from Serial.println(); /* This example shows basic usage of the MultiTrellis object controlling an array of NeoTrellis boards As is this example shows use of two NeoTrellis boards connected together with the leftmost board having the default I2C address of 0x2E, and the rightmost board having the address of 0x2F (the A0 jumper is soldered) */ #include "Adafruit_NeoTrellis.h" #include "MIDIUSB.h" #define Y_DIM 8 //number of rows of key #define X_DIM 16 //number of columns of keys #define OFF (0, 0, 0) //nil //create a matrix of trellis panels Adafruit_NeoTrellis t_array[Y_DIM/2][X_DIM/4] = { { Adafruit_NeoTrellis(0x32), Adafruit_NeoTrellis(0x30), Adafruit_NeoTrellis(0x2F), Adafruit_NeoTrellis(0x2E) }, { Adafruit_NeoTrellis(0x33), Adafruit_NeoTrellis(0x31), Adafruit_NeoTrellis(0x3E), Adafruit_NeoTrellis(0x36) } }; int trellisButtonState[128] ={ 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, 0,0,0,0, }; //pass this matrix to the multitrellis object Adafruit_MultiTrellis trellis((Adafruit_NeoTrellis *)t_array, Y_DIM/2, X_DIM/4); // Input a value 0 to 255 to get a color value. // The colors are a transition r - g - b - back to r. uint32_t Wheel(byte WheelPos) { return seesaw_NeoPixel::Color(70,0,0); return 0; } //define a callback for key presses TrellisCallback blink(keyEvent evt){ if(evt.bit.EDGE == SEESAW_KEYPAD_EDGE_RISING){ if(trellisButtonState[evt.bit.NUM]==0){ trellis.setPixelColor(evt.bit.NUM, Wheel(map(evt.bit.NUM, 0, X_DIM*Y_DIM, 0, 255))); //on rising trellisButtonState[evt.bit.NUM]=1; trellis.show();} else if(trellisButtonState[evt.bit.NUM]==1){ trellis.setPixelColor(evt.bit.NUM, 0);//on rising trellisButtonState[evt.bit.NUM]=0; trellis.show();} } /* else if(evt.bit.EDGE == SEESAW_KEYPAD_EDGE_FALLING) trellis.setPixelColor(evt.bit.NUM, 0); //off falling */ // trellis.show(); return 0; } void setup() { Serial.begin(9600); //while(!Serial) delay(1); if(!trellis.begin()){ Serial.println("failed to begin trellis"); while(1) delay(1); } /* the array can be addressed as x,y or with the key number */ for(int i=0; i<Y_DIM*X_DIM; i++){ trellis.setPixelColor(i, Wheel(map(i, 0, X_DIM*Y_DIM, 0, 255))); //addressed with keynum trellis.show(); delay(50); } for(int y=0; y<Y_DIM; y++){ for(int x=0; x<X_DIM; x++){ //activate rising and falling edges on all keys trellis.activateKey(x, y, SEESAW_KEYPAD_EDGE_RISING, true); trellis.activateKey(x, y, SEESAW_KEYPAD_EDGE_FALLING, true); trellis.registerCallback(x, y, blink); trellis.setPixelColor(x, y, 0x000000); //addressed with x,y trellis.show(); //show all LEDs delay(50); } } } void noteOn(byte channel, byte pitch, byte velocity) { midiEventPacket_t noteOn = {0x09, 0x90 | channel, pitch, velocity}; MidiUSB.sendMIDI(noteOn); MidiUSB.flush(); } void noteOff(byte channel, byte pitch, byte velocity) { midiEventPacket_t noteOff = {0x08, 0x80 | channel, pitch, velocity}; MidiUSB.sendMIDI(noteOff); MidiUSB.flush(); } void loop() { trellis.read(); delay(20); }

[image] shades77: However, what I am trying to do is probably so simple I can' t really find any examples. [image] How to get the best out of this forum Programming Questions Welcome to the Arduino forum! A guide explaining how to get the best out of this forum is available at the link below. Please read it: best regards Stefan

This is one of the most unhepful responses I have ever received. Why on earth would you even bother to write such a condescending and uselss response? Have you nothing else to do? Of course I went through examples and the M4 library is not applicable to the multitrellis/neoTreliis. Maybe you should read your own links. Thanks for nothing.

"be the change you want to see in the world" - yah... so, I will hope that the bad vibes here don't spoil someone else from perhaps offering a more helpful response than Herr Ludwig offered: B: learn to program. I am pretty sure there is an alternative...like: C: here is where the MIDI info would go in the code you attached, here is a better way to address the color of buttons in the code you attached... or here is a USEFUL link to a relevant aspect related to the code you attached. Thanks in advance.

It looks to me like your defining a 4 x 4 array but only initializing it with 8 elements: [image] shades77: Adafruit_NeoTrellis t_array[Y_DIM/2][X_DIM/4] = { { Adafruit_NeoTrellis(0x32), Adafruit_NeoTrellis(0x30), Adafruit_NeoTrellis(0x2F), Adafruit_NeoTrellis(0x2E) }, { Adafruit_NeoTrellis(0x33), Adafruit_NeoTrellis(0x31), Adafruit_NeoTrellis(0x3E), Adafruit_NeoTrellis(0x36) } }; [image] shades77: I also tried to monitor it in the Serial Monitor but got nothing in response from Serial.println(); I don't see Serial.println() being used anywhere in your code except once it setup(). I don't see where you've initialized the MIDI object, or done anything with your noteOn() / noteOff() functions. If it were my project, I'd start with just getting the NeoTrellis to behave as you want and substitute Serial.print() calls for the MIDI stuff. Then go through the MIDI library's examples and really learn how to use it. Then, add the MIDI stuff to the NeoTrellis code. Keep the Serial.print calls until you're sure the MIDI calls are correlated with them. [image] shades77: Plus, I have no desire to do anything else with Arduino Then perhaps the best alternative is to pay someone to write the code for you. Start by posting the project HERE.

Thanks for this, perhaps I attached the code without some adjustments I made that included MIDI and a Serial callback (which I placed in the MIDI function). The grid works and all buttons can be addressed so I think the layout is ok. It is recognized as a MIDI device and I can reprogram the colors in masse with the example funtionc. Question is where the MIDI functions go so that they transmit to the software? Do I need to define a channel out? And, how can individual buttons be addressed. I don't quite understand the KEY address method. I just need this to send midinote 1 when I press button 1 and so on. I don't see any clear examples of this in my searches, so thought I'd ask the community. Thanks though for actually trying to be helpful and for the link to the Project forum. > /* This example shows basic usage of the > MultiTrellis object controlling an array of > NeoTrellis boards > > As is this example shows use of two NeoTrellis boards > connected together with the leftmost board having the > default I2C address of 0x2E, and the rightmost board > having the address of 0x2F (the A0 jumper is soldered) > */ > > #include "Adafruit_NeoTrellis.h" > #include "MIDIUSB.h" > > #define Y_DIM 8 //number of rows of key > #define X_DIM 16 //number of columns of keys > > #define OFF (0, 0, 0) //nil > #define RED = (255, 0, 0) // 2's > #define GREEN = (0, 255, 0) // 3's > #define CYAN = (0, 255, 255) // 5's > #define YELLOW = (255, 150, 0) // 7's > #define BLUE = (0, 0, 255) // 11's > #define PURPLE = (180, 0, 255) // 13's > > //create a matrix of trellis panels > Adafruit_NeoTrellis t_array[Y_DIM/2][X_DIM/4] = { > > { Adafruit_NeoTrellis(0x32), Adafruit_NeoTrellis(0x30), Adafruit_NeoTrellis(0x2F), Adafruit_NeoTrellis(0x2E) }, > > { Adafruit_NeoTrellis(0x33), Adafruit_NeoTrellis(0x31), Adafruit_NeoTrellis(0x3E), Adafruit_NeoTrellis(0x36) } > > }; > > int trellisButtonState[128] ={ > 0,0,0,0, 0,0,0,0, > 0,0,0,0, 0,0,0,0, > 0,0,0,0, 0,0,0,0, > 0,0,0,0, 0,0,0,0, > 0,0,0,0, 0,0,0,0, > 0,0,0,0, 0,0,0,0, > 0,0,0,0, 0,0,0,0, > 0,0,0,0, 0,0,0,0, > 0,0,0,0, 0,0,0,0, > 0,0,0,0, 0,0,0,0, > 0,0,0,0, 0,0,0,0, > 0,0,0,0, 0,0,0,0, > 0,0,0,0, 0,0,0,0, > 0,0,0,0, 0,0,0,0, > 0,0,0,0, 0,0,0,0, > 0,0,0,0, 0,0,0,0, > }; > > > //pass this matrix to the multitrellis object > Adafruit_MultiTrellis trellis((Adafruit_NeoTrellis *)t_array, Y_DIM/2, X_DIM/4); > > // Input a value 0 to 255 to get a color value. > // The colors are a transition r - g - b - back to r. > > uint32_t Wheel(byte WheelPos) { > if(WheelPos -= 170) { > return seesaw_NeoPixel::Color(WheelPos * 2, 255 - WheelPos * 3, 0); > > } > return 0; > } > > void noteOn(byte channel, byte pitch, byte velocity) { > midiEventPacket_t noteOn = {0x09, 0x90 | channel, pitch, velocity}; > MidiUSB.sendMIDI(noteOn); > MidiUSB.flush(); > Serial.println("note on"); > } > > void noteOff(byte channel, byte pitch, byte velocity) { > midiEventPacket_t noteOff = {0x08, 0x80 | channel, pitch, velocity}; > MidiUSB.sendMIDI(noteOff); > MidiUSB.flush(); > } > > > //define a callback for key presses > TrellisCallback blink(keyEvent evt){ > > if(evt.bit.EDGE == SEESAW_KEYPAD_EDGE_RISING){ > > if(trellisButtonState[evt.bit.NUM]==0){ > trellis.setPixelColor(evt.bit.NUM, Wheel(map(evt.bit.NUM, 0, X_DIM*Y_DIM, 0, 255))); //on rising > trellisButtonState[evt.bit.NUM]=1; > > trellis.show();} > > else if(trellisButtonState[evt.bit.NUM]==1){ > trellis.setPixelColor(evt.bit.NUM, 0);//on rising > trellisButtonState[evt.bit.NUM]=0; > > trellis.show();} > } > /* > else if(evt.bit.EDGE == SEESAW_KEYPAD_EDGE_FALLING) > trellis.setPixelColor(evt.bit.NUM, 0); //off falling > */ > // trellis.show(); > return 0; > } > > void setup() { > Serial.begin(9600); > //while(!Serial) delay(1); > > if(!trellis.begin()){ > Serial.println("failed to begin trellis"); > while(1) delay(1); > } > > /* the array can be addressed as x,y or with the key number */ > for(int i=0; i trellis.setPixelColor(i, Wheel(map(i, 0, X_DIM*Y_DIM, 0, 255))); //addressed with keynum > trellis.show(); > delay(50); > } > > for(int y=0; y for(int x=0; x //activate rising and falling edges on all keys > trellis.activateKey(x, y, SEESAW_KEYPAD_EDGE_RISING, true); > trellis.activateKey(x, y, SEESAW_KEYPAD_EDGE_FALLING, true); > trellis.registerCallback(x, y, blink); > trellis.setPixelColor(x, y, 0x000000); //addressed with x,y > trellis.show(); //show all LEDs > delay(50); > } > } > > } > > > > void loop() { > trellis.read(); > delay(20); > }

[image] shades77: The grid works and all buttons can be addressed so I think the layout is ok. Then can you explain why you're defining an array to hold 16 elements but only populating it with 8?

[image] shades77: I don't see any clear examples of this in my searches, so thought I'd ask the community. I have not used MIDI on T4. But there are 9 built in MIDI examples in the Arduino IDE with the T4 board selected. Are you saying none of them are helpful?

No, I can't, I'm hacking code I found. How should it be formatted? It seems to run the grid fine when uploaded and all buttons respond when pressed, etc. I thought this defined a grid of boards that was 2 by 4? Perhaps you could suggest a correction to the syntax? I am using a hacked example of the examples so, I guess it must be true that I did not find the helpful. I'm quite confused by the attitude on this forum to be honest. I mean, sorry to put you all out with some questions. Again, I appreciate your helpful suggestions.

Do you mean M4 when you write T4? From what I tried none of that code would work with a larger grid... but probably misunderstanding this because as the subject line says: beginner. Again - I am happy to hire someone, but will do that locally if need be, however, I do feel that this code only needs to be adjusted slightly to send the simple information I'm looking for. Thanks again!

[image] shades77: How should it be formatted? Presumably an array that represents a 2 x 4 grid of objects would defined as 2 x 4: Adafruit_NeoTrellis t_array[2][4] = { { Adafruit_NeoTrellis(0x32), Adafruit_NeoTrellis(0x30), Adafruit_NeoTrellis(0x2F), Adafruit_NeoTrellis(0x2E) }, { Adafruit_NeoTrellis(0x33), Adafruit_NeoTrellis(0x31), Adafruit_NeoTrellis(0x3E), Adafruit_NeoTrellis(0x36) } }; [image] shades77: running through a Teensy 4.0 T4 == Teensy 4.0 Like I said, I've not used MIDI on T4. It's unclear to me how MIDIUSB interacts with the standard MIDI library. But since you haven't attached your callback functions to any MIDI events, it's obvious that they will never be called and nothing will happen with them. You might have better luck posting your question on the PJRC forums. The users there are quite experienced.

NeoTrellis and Teensy Questions/help

Projects Programming

StefanL38 November 12, 2022, 4:31pm 2

best regards Stefan

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