Babygnusbuino
A ridiculously small Arduino with USB interface for bootloading and/or MIDI connection, based on the gnusb / Gnusbuino project.
Really bare-bones, no protection, no FTDI chip, single-sided PCB, no holes. The USB connector is directly etched on the board, so you actually plug in the PCB itself to upload a new sketch to the Arduino.
Attention This project is still work in progress - more of a proof of concept. I'm able to upload a blink sketch and it works, but there is some testing to be done. Hardware design could change - not sure if this is the best pin configuration - and the bootloader is a bit sketchy…
Building
Parts List
The only parts needed are:
- 1 Atmel Attiny85 microprocessor
- 2 resistors 68 Ohms
- 2 zeners 3.3V
- 1 resistor 1k6
- 1 capacitor 100n
Circuit Schematic
Pin Definitions, v2
// ATMEL ATTINY85 / BABYGNUSBUINO // // +---\/---+ // !RESET (AD 0) PB5 1| |8 VCC // (D3/A3)PWM? PB3 2| |7 PB 2 / USB+ // (D4/A4)PWM? PB4 3| |6 PB 1 / USB- // GND 4| |5 PB 0 / USB-PULLUP (D0/A40)PWM? // +--------+ //
Pin Definitions, v3 as DigiSpark
Pin outs: All pins can be used as Digital I/O
- Pin 0 → I2C SDA, PWM (LED on Model B)
- Pin 1 → PWM (LED on Model A) Pin
- 2 → I2C SCK, Analog
- Pin 3 → Analog In (also used for USB+ when USB is in use)
- Pin 4 → PWM, Analog (also used for USB- when USB is in use)
- Pin 5 → Analog In
// ATMEL ATTINY45 / ARDUINO // // +-\/-+ // Ain0 (D 5) PB5 1| |8 Vcc // USB+ / Ain3 (D 3) PB3 2| |7 PB2 (D 2) Ain1 // USB- / Ain2 (D 4) PB4 3| |6 PB1 (D 1) pwm1 // GND 4| |5 PB0 (D 0) pwm0 // +----+
PCB
File the board so that the brackets around the DIY USB connector are just barely visible, this should give the right fit.
Most PCB material is a little too thin, so this connector wiggles a lot inside the USB port - it's best to glue some cardboard or thin aluminum to the back of the board to make it slightly thicker.
Full SMD version
Scaled 400%
DIL version
Scaled 400%, die löcher grad wegmachen oder.... ist ja pseudo-smd
Bio Baby hackteria DIL/SMD-version
LIFEPATCH-BabyGnusbuino DIL-version
File:BabyPatchuino DIL v03.zip
BabyHONFuino DIL-version
Programming
Source Code
The source code can be found in the SVN repository of the Gnusbuino [[1]]
Building / Installing
Hardware schematics and source code are in the SV repository at http://gnusb.svn.sourceforge.net/viewvc/gnusb/branches/gnusbuino/
You can either download the two folders and add their contents to the corresponding folders in your Arduino working directory, or you can pull the latest version directly through svn.
cd "the/path/to/Arduino/" (for me on a Mac it is cd ~/Users/me/Documents/Arduino) svn co https://gnusb.svn.sourceforge.net/svnroot/gnusb/branches/gnusbuino/hardware svn co https://gnusb.svn.sourceforge.net/svnroot/gnusb/branches/gnusbuino/libraries
later on, you can always update to the latest version by typing
svn update
Flashing the bootloader
The Bootloader is based on the USBasploader-tiny85 [[2]] - and of course on V-USB [[3]], the virtual USB driver from objective-development.
To get as small as possible, the board does not contain a ISP connector. We'd need it only once to flash the bootloader, anyway. From then on the chip can be reprogrammed directly trough USB. In order to flash the small outline smd chip, I made an adapter plate for the Gnusb-Prog (see: [[4]]) - where the chip is mounted temporarily and held in place with a paper clip:
File:Babygnusb programmer eagle.zip
Bootloader:
avrdude -P /dev/ttyUSB0-b 19200 -c avrisp -p t85 -U flash:w:attiny85.hex:i
Fuses:
avrdude -P /dev/ttyUSB0 -b 19200 -c avrisp -p t85 -U lfuse:w:0xe1:m -U hfuse:w:0xdd:m -U efuse:w:0xfe:m
maybe change the devices on your OS
Avrdude issues
Unfortunately, the current ATTINY85 bootloader does not cope well with the speed at which it gets its data from avrdude, so the Arduino IDE does not work out of the box to program the Babygnusbuino. You'll have to compile a slower version of avrdude and replace the one that comes with Arduino (inside the Arduino Application).
(from my read me file:)
- download avrdude source code here[[5]] (I was using 5.11)
- replace the file usbasp.c with the one in variants/attiny85/avrdude patch
- compile avrdude:
./configure
make
- replace the file /Applications/Arduino.app/Contents/Resources/Java/hardware/tools/avr/bin/avrdude with the newly compiled one
see also https://github.com/embedded-creations/USBaspLoader-tiny85/issues/1
Still, I sometimes have to try uploading three times until the "broken pipe" errors go away. Still work to do on this bootloader, guys…
Precompiled Binaries
MacOS X
Here is a patched version of avrdude - compiled for MacOS X 10.7. Nut sure if it works with other versions.
this is the compiled version of avrdude with libusb, i tested it on snow leopard and mountain lion so it should works on lion too (manticore)
File:Avrdude.5.11.1-libusb.zip
win 7
Here is a version of avrdude - compiled for Windows 7 x64
File:Avrdude-5.11-win7-x64-Gnusbuino-Hack.zip
A manual on how to compile avrdude for windows from source can be found here: http://tomeko.net/other/avrdude/building_avrdude.php (Note for the manual: in the libusb version 1.2.6.0 you have to rename "lusb0_usb.h" to "usb.h" so the avrdude source compiles fine.)
Uploading a sketch
When you plug in the Babygnusbuino it will first start into the bootloader and present itself as "USBasp" to the host computer. After about five seconds, if there's no activity, it will automatically start the main program. To upload a sketch:
- plug in Babygnusbuino
- within 2-3 seconds hit the "upload" button in Arduino
Sometimes I have to try several times - the timing is not always easy to get right. Also, bootloader is still a bit shaky, doesn't work every time. Be sure to read the results in the debug window.
Questions
- what to do with the boards.txt file? (dusjagr)
- Just leave it in .Documents/Arduino/hardware/Gnusbuino/
- where to put stuff in linux? (avrdude is here: ./arduino-1.0.1/hardware/tools/)
- I'd rename ./arduino-1.0.1/hardware/tools/avrdude to avrdude_bak or something, just in case. Then put new hacked avrdude at its place
- what about the reset pin, aka PB5?
- still no sure about that one. I wanted to leave it a reset so I can jump into bootloader without unplugging/replugging the thing. But on my board that doesn't seem to work, somehow. Otherwise you can set fuses to have it as a normal pin - but then you cannot reflash the bootloader anymore. As this project is pretty fresh (and the bootloader seems somewhat crappy, that doesn't seem to be very clever, for the moment).
- Another Pin that could probably be freed up is PB0 - and tying D- through 1k6 directly to VCC. I needed this mechanism on the original gnusb for usb disconnecting and reconnecting but I'm not sure if it is really needed in this case. Will make some more research (don't disable RESET, yet ;-)
- just hack the pins_arduino.h and add PB0 as Pin 2, and there you go. dont even need to change the resitor. we soldered the PD0 to the pads, where reset used to go
- seems the easy logger just has a 2.2k resistor from vcc to D-....
- can i send info/data to a computer? to use it in pd or similar software?
- UPDATE: MIDI seems to work now on the Babygnusbuino, too. Use svn update to get the newest version
I'll try to adapt the Midignusbuino core for the Attiny85 as soon as I can. The first idea was to emulate a standard serial-class-device (CDC-Class) but apparently that could prove to be more difficult: "The back door to the low-speed bulk transfer is gradually closing on the newer OS. After enjoying this USB technology, switch to the HID protocol or to MCU having on-chip USB controller." [6] (mirdej) - MIDI works super for PD
- UPDATE: MIDI seems to work now on the Babygnusbuino, too. Use svn update to get the newest version
- what are they doing http://www.obdev.at/products/vusb/easylogger.html
- I choose the Babygnusbuino in the arduino /Tools/Board but which programmer?
- no need to chose a programmer - the boards.txt file defines USBasp as the programmer
- can i burn the bootloader from the Arduino IDE, with eg. Arduino-ISP? using an ISP connection?
- should work (before soldering the chip on board)
- on what internal clock is the Attiny85? 1MHZ? 8MHZ?
- 16.5 Mhz internal PLL, calibrated to +/- 1% by listening to USB packets
- avrdude -P /dev/ttyUSB0 -b 19200 -c avrisp -p t85 -U lfuse:w:0xe1:m -U hfuse:w:0xdd:m -U efuse:w:0xfe:m (something like this?)
- exactly the fuses I used, too: -U lfuse:w:0xe1:m -U hfuse:w:0xdd:m-U efuse:w:0xfe:m
- my arduino IDE doesnt see the USBasp
- check your soldering and make sure u had the right parts
- timing when you plug in your Baby..
Installing it on ubuntu 12.04/linux (dusjagr)
- download the gnusbuino folder from here: http://gnusb.svn.sourceforge.net/viewvc/gnusb/branches/gnusbuino/
- copy the folder ./gnusbuino/hardware/Gnusbuino into your personal arduino folder ~/sketchbook/hardware/* create the hardware folder yourself if needed.
- make the avrdude as described above
- had to install: (in addition to many things already there)
- bison
- flex
- libusb-devel
- and remove:
- byacc-j
- had to install: (in addition to many things already there)
- copy avrdude into folder ./arduino-1.0.1/hardware/tools
- device showed up with "lsusb" as: Bus 001 Device 007: ID 16c0:05dc VOTI shared ID for use with libusb
- had to change "only root access" for usbasp as described here:
- The fix: Create a file called 10-usbtinyisp.rules in directory /etc/udev/rules.d
# USBtinyISP Programmer rules SUBSYSTEMS=="usb", ATTRS{idVendor}=="1781", ATTRS{idProduct}=="0c9f", GROUP="adm", MODE="0666" SUBSYSTEMS=="usb", ATTRS{idVendor}=="16c0", ATTRS{idProduct}=="0479", GROUP="adm", MODE="0666" # USBasp babygnuspuino Programmer rules SUBSYSTEMS=="usb", ATTRS{idVendor}=="16c0", ATTRS{idProduct}=="05dc", GROUP="adm", MODE="0666"
- Then execute:
sudo restart udev
Ideas
- what about a short digitalRead in the beginning of the bootloader (maybe at one of the USB pins?) so if a jumper is set, it directly goes into the program. so it start faster if installed.
- set the usb pins as outputs and turn all them off at the end of the bootloader.
- implement the servo library http://www.cunningturtle.com/attiny4585-servo-library/
other stuff
der frickelt auch mit ner spezial version von arduino.... http://www.kickstarter.com/projects/digistump/digispark-the-tiny-arduino-enabled-usb-dev-board/posts/350928
Example Code
we got some pseudo PWM working using interupts... see example below. but the delay is wrong, something has to be fixed with the timers...
setup()
best to set the pins used for programming via USB again as outputs and low, before starting your program
void setup()
{ // Set pins
pinMode(0, OUTPUT);
pinMode(1, OUTPUT);
pinMode(2, OUTPUT);
digitalWrite(0, LOW);
digitalWrite(1, LOW);
digitalWrite(2, LOW);
}
PWM Heartbeat
/*
babygnusbuino: Fading
*/
int PWM_Pin = 0; // LED connected to digital pin 0
int PWM_value = 0;
int wait = 30;
volatile unsigned char e = 0;
void setup()
{
// Timer Init
TCCR0A = (0 << WGM02) | (0 << WGM01) | (0<< WGM00); // Normal Mode 000
TCCR0B = (0 << CS02) | (0 << CS01) | (1<< CS00); // Clock Select no prescaling 001
TIMSK = (1 << TOIE1); // Overflow interrupt is enabled
sei(); // set Global Interrupt Enable
// Set pins
pinMode(PWM_Pin, OUTPUT);
digitalWrite(0, LOW);
}
void loop()
{
for (int c = 0; c < 255; c++) {
PWM_value = c;
delay (wait);
}
for (int c = 255; c > 0; c--) {
PWM_value = c;
delay (wait);
}
}
//Overflow routine for Timer 1
ISR(TIM1_OVF_vect) {
if(e==255) {
e=0;
digitalWrite(PWM_Pin, HIGH);
}
if (PWM_value == e) {
digitalWrite(PWM_Pin, LOW);
}
e++;
}
3 Channels PWM
/*
babygnusbuino: PWM 3 Channels
*/
int PWM_Pin0 = 0; // LED connected to digital pin 0
int PWM_Pin1 = 1; // LED connected to digital pin 0
int PWM_Pin2 = 2; // LED connected to digital pin 0
int PWM_Pin0_value = 0;
int PWM_Pin1_value = 0;
int PWM_Pin2_value = 0;
int wait = 300;
volatile unsigned char e = 0;
void setup()
{
// Timer Init
TCCR0A = (0 << WGM02) | (0 << WGM01) | (0<< WGM00); // Normal Mode 000
TCCR0B = (0 << CS02) | (0 << CS01) | (1<< CS00); // Clock Select no prescaling 001
TIMSK = (1 << TOIE1); // Overflow interrupt is enabled
sei(); // set Global Interrupt Enable
// Set pins
pinMode(PWM_Pin0, OUTPUT);
pinMode(PWM_Pin1, OUTPUT);
pinMode(PWM_Pin2, OUTPUT);
}
void loop()
{
for (int c = 0; c < 255; c++) {
PWM_Pin2_value = c;
delay (wait);
}
for (int c = 255; c > 0; c--) {
PWM_Pin2_value = c;
delay (wait);
}
}
//Overflow routine for Timer 1
ISR(TIM1_OVF_vect) {
if(e==255) {
e=0;
digitalWrite(PWM_Pin0, HIGH);
digitalWrite(PWM_Pin1, HIGH);
digitalWrite(PWM_Pin2, HIGH);
}
if (PWM_Pin0_value == e) {
digitalWrite(PWM_Pin0, LOW);
}
if (PWM_Pin1_value == e) {
digitalWrite(PWM_Pin1, LOW);
}
if (PWM_Pin2_value == e) {
digitalWrite(PWM_Pin2, LOW);
}
e++;
}
RGB Led
/***
babygnusbuino blend
***/
#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/delay.h>
int LED0 = 0; // Blue
int LED1 = 1; // Red
int LED2 = 2; // Green
volatile unsigned char e = 0;
volatile unsigned char BRGLed[3] = {0,0,0};
void setup()
{
randomSeed(analogRead(0));
// Timer Init
cli();
TCCR0A = 0x00;
TCCR0B = 0x01;
TIMSK = (1 << TOIE1); // Overflow
sei();
pinMode(LED0, OUTPUT);
pinMode(LED1, OUTPUT);
pinMode(LED2, OUTPUT);
}
void loop()
{
int r = random(0,255);
int g = random(0,220);
int b = random(0,220);
for (int a = 0; a < 60; a++) {
delay(8000);
blend(r,g,b,a); // r g b alpha
}
}
/*
blend color
@param r Red
@param g Green
@param b Blue
@param da Alpha: the factor how much the new color will be blended with the existing color. da = 0: no change, da = 255: new color will be set (no blending).
*/
void blend(int r, int g, int b, int da) {
// source alpha
int sa = 255 - da;
int tb = (sa * BRGLed[0] + da * b) + 128;
int tr = (sa * BRGLed[1] + da * r) + 128;
int tg = (sa * BRGLed[2] + da * g) + 128;
BRGLed[0] = ((tb>>8)+tb)>>8;
BRGLed[1] = ((tr>>8)+tr)>>8;
BRGLed[2] = ((tg>>8)+tg)>>8;
}
// Overflow routine for Timer 1
ISR(TIM1_OVF_vect) {
if(e==255) {
e=0;
digitalWrite(LED0, HIGH);
digitalWrite(LED1, HIGH);
digitalWrite(LED2, HIGH);
}
if (BRGLed[0] == e) {
digitalWrite(LED0, LOW);
}
if (BRGLed[1] == e) {
digitalWrite(LED1, LOW);
}
if (BRGLed[2] == e) {
digitalWrite(LED2, LOW);
}
e++;
}
Flickering RGB Led
/*
flickering RGB LED!
*/
#include <avr/io.h>
#include <util/delay.h>
unsigned long lfsr = 1;
unsigned char temp;
/**
* delay
* @param ms duration in milliseconds
*/
void delay_ms(uint16_t ms)
{
for (uint16_t i = 0 ; i < ms ; i++) {
_delay_ms (1); // Loop delay
}
}
void setup()
{
DDRB = 0xff;
}
void loop() {
lfsr = (lfsr >> 1) ^ (-(lfsr & 1u) & 0xd0000001u); /* taps 32 31 29 1 */
temp = (unsigned char) lfsr; // take lowest eight bits
DDRB = ~temp; // declare those pins as output where temp is zero
PORTB = temp << 2; // give the value of 0 to the output pins
temp = (unsigned char) (lfsr >> 24);
_delay_loop_2(temp<<7);
delay_ms(100);
}
8-bit Noise
/* Pseudo-Random Bit Sequence Generator 2009-11-25 */
/* Copyright (c) 2009 John Honniball, Dorkbot Bristol */
/*
* For a discussion of PRBS generators, see The Art Of Electronics, by
* Horowitz and Hill, Second Edition, pages 655 to 660. For more info
* on Linear Feedback Shift Registers, see Wikipedia:
* http://en.wikipedia.org/wiki/Linear_feedback_shift_register
* For the actual shift register taps, refer to this article on noise
* generation for synthesisers:
* http://www.electricdruid.net/index.php?page=techniques.practicalLFSRs
*/
// Choose the same pin as the "Melody" example sketch
int speakerPin = 0;
int potiPin = A3;
unsigned int analogValue;
int samplingDelay;
unsigned long int reg;
void setup ()
{
// Serial setup for debugging only; slows down the program far too much
// for audible white noise
//Serial.begin (9600);
// Connect a piezo sounder between Ground and this pin
pinMode (speakerPin, OUTPUT);
// Arbitrary inital value; must not be zero
reg = 0x551155aaL;
}
void loop ()
{
unsigned long int newr;
unsigned char lobit;
unsigned char b31, b29, b25, b24;
// Extract four chosen bits from the 32-bit register
b31 = (reg & (1L << 31)) >> 31;
b29 = (reg & (1L << 29)) >> 29;
b25 = (reg & (1L << 25)) >> 25;
b24 = (reg & (1L << 24)) >> 24;
// EXOR the four bits together
lobit = b31 ^ b29 ^ b25 ^ b24;
// Shift and incorporate new bit at bit position 0
newr = (reg << 1) | lobit;
// Replace register with new value
reg = newr;
// Drive speaker pin from bit 0 of 'reg'
digitalWrite (speakerPin, reg & 1);
// Display 'reg' in the serial console for debugging only
// Serial.println (reg, HEX);
samplingDelay = 1 + (2*(analogRead(potiPin)>>0));
// Delay corresponds to 20kHz, but the actual frequency of updates
// will be lower, due to computation time and loop overhead
delayMicroseconds (samplingDelay);
// If the above delay is increased to a few tens of milliseconds,
// and the piezo sounder is replaced by an LED and a suitable series
// resistor, a randomly flashing light will result. Several LEDs
// could be driven from various bits of the shift register.
}