For this sort of signal speed a low-impedance probe might be the best option, basically a 10:1 probe with 500 ohms input impedance and using 50 ohm setting at the scope. High impedance probes are capacitive-dividers at the top end of their...
Thanks Paul for your Tips.
My 150 MHz signal with an Rigol MSO5104 (hacked to 350 MHz). I set the probe to x10 to make the measurement more precise.
Code:
const int my_pulse_pin = 20;
void setup()
{
pinMode(my_pulse_pin, OUTPUT)...
Nice Jeannie project. I also had the idea of using the Teensy 4.0 for digital effects. But the question is, can you clone the beautiful effects from the FV-1 with the Teensy 4.0?
My prototype schematic is finished. One or two things will definitely change. For example, the decision as to which effect module will be used in the Degenerator2 isn't quite clear yet. But the time will come, and the idea will come ;-) With that...
Just wanted to report back that the code works. Thanks!
I removed the fade in Audacity, so I removed setLoopStart() and setLoopFinish() aswell.
When I extend the crossfade, the loop is almost inaudible.
Hello friends :)
The first circuit diagrams from Degenerator2. Circuit diagrams for the MCU, power supply, MIDI, and display are coming soon.
The control panel consists of seven ATiny404 modules. Each module has an analog input for four buttons...
But..there is something wrong with your calculation for the sample rate :unsure:
// map analog input 0-1023 to 0.5-3.0 pitch
double getPlaybackRate(int16_t analog) { //analog: 0..1023
return ((analog / 1023) * 2.5) + 0.5;
This is my...
The test was successful. Teensy plays the sample :)
This my code..
#include <Arduino.h>
#include <Audio.h>
#include <SD.h>
#include <TeensyVariablePlayback.h>
// GUItool: begin automatically generated code
AudioPlaySdResmp playSdWav1...
You still need to set the loop_type :unsure:
In the loop_type.h define this..
typedef enum loop_type {
looptype_none, // 0
looptype_repeat, // 1
looptype_pingpong // 2
} loop_type;
play sample..
float rate =...
My Led panel..
My Teensy code..
// LED driver
// Pin connected to ST_CP of 74HC595
int latchPin = 30;
// Pin connected to SH_CP of 74HC595
int clockPin = 31;
// Pin connected to DS of 74HC595
int dataPin = 32;
// Pin connected to OE of 74HC595...
Ok. I think it's the problem comes from the +3.3V supply voltage from Teensy Board. The Teensy gets its +5V supply voltage on pin Vin (yellow curve). After 15ms, the TLV75733P chip on the Teensy switches on the +3.3V supply voltage on the 3.3V...
It's clearly due to my power supply in the DIY project.
1st image shows a 4.7K pull-up on Teensy4.1 pin 29 with +5V and +3.3V from the Teensy.
2nd image shows a 4.7K pull-up on Teensy4.1 pin 29 with +5V and +3.3V from the DIY project's power...
As I suspected, it's the power supply. My test power supply delivers a stable 5V supply voltage immediately after switching off from standby. The voltage regulator on my DIY board takes a few milliseconds to adjust the voltage from +12V to +5V...
Mmmm :unsure:
I've now used a Teensy4.0 board and am getting different results. Since the Teensy4.0 doesn't have pin 29, I used a different pin 2 with an external 4.7K pull-up connected to +3.3V from the Teensy. The signal is almost identical...
I can't explain it either. The pull-up resistor is connected to a separate 3.3 volt line. Perhaps that's the cause. I supply the entire circuit with +12V. The Teensy is supplied with +5V via a switching regulator. I generate the +3.3V using a...
Init the light shown on my Synth project..
There are 24 status LEDs in different colors for the 24 keys. These are controlled by three 74HC595 slide switches. For some keys, the LEDs are not yet wired.
pinMode(29, INPUT_PULLUP);
pinMode(29, OUTPUT);
digitalWriteFast(29, HIGH);
4.7K and I also tried different pins on the Teensy and always tested in connection to the gate input of the 74HC595.
Measured here with 4.7K pullup on the Teensy pin...
pinMode(29, INPUT_PULLUP);
pinMode(29, OUTPUT);
digitalWriteFast(29, HIGH);
The oscilloscope shows the voltage rise of the supply voltage (blue) and pin 29 (Gate 74hc595) on the Teensy4.1 (yellow) during power-up.
The gate pin on the 74HC595...
Hallo Teensys..
I had a similar problem. I'm using three 74HC595s on the Teensy4.1. During power-up, the 74HC595 outputs had random values, and some LEDs were lit. Solution: I connected the gate pin of the 74HC595 to a Teensy control line using a...
All buttons are illuminated! Below the mod control is the fixed control for filter resonance.
With the buttons Mod 1-4 a different modulator source can be selected and controlled with the Modulation controller.
A sign of life...
I think I'll choose a dark blue as the background color for all the LEDs on the LED ring, and change to orange when I turn up the volume.
Another update...
All knobs and buttons are installed and positioned. I've reordered some black and transparent keycaps. There's also an LED ring for the modulation knob. It's sure to look great. We'll see...
LED-Ring
This is the schematic of Micro Dexed Touch Synthesizer. It also uses a PCM5102 DAC on Teensy 4.1.
Info: Vin on the PCM5102 DAC is not 3.3V but must be +5V.
For the keys, I chose nice, soft Cherry keys with transparent and black keycaps.
Since the keys can be fitted with LEDs, I will also install blue LEDs. There will also be a nice, large red modulation encoder made of aluminum to control the cutoff...
I have been using Duppa products in my projects for a long time. They work very well and allow you to connect many encoders with only 2 pins of the Teensy. Duppa also sells very easy to use i2c led rings.
To query many encoders, I use a small I2C interface for each encoder. Up to 256 encoders can be queried. It saves valuable computing time on the Teensy and is easy to query.
My video
Link...
Hi guys,
I finally managed to finish and release my DIY synthesizer project, hope it is of use or inspiration to anyone!
TeensyMix synth is an 8-voice polyphonic synthesizer based on the Teensy 4.1 development board. It is designed to be an...
Nice project :) The next step for your synth would be manual operation without a midi controller.
My Teens Synth "Jeannie"
Video 1:
Video 2:
Teensy project: https://forum.pjrc.com/index.php?threads/new-teensy-4-1-diy-synthesizer.63255/
Hello there..
The ordered prototype PCB board with the buttons arrived today. The board has a size of 320 x 200 mm and has round solder pads on both sides. So there is enough space for a lot of control elements such as encoders, buttons and...