Introduction: Building an ISP Shield for Arduino
Some astute Instructablites have asked. What does this do? Well essentially this shield can turn your Arduino into a quite capable chip programmer. What's more is that it can allow your Arduino to make more Arduino compatible devices. So with this shield, a bit of code and some some spare chips you can replicate what your Arduino does for a fraction of the cost. Not only using the same chip as your Arduino uses but also some smaller cheaper ones too. Like the ATTiny85.
Let me start by saying to program an AVR chip with an Arduino you don't need a shield or even a crystal if you're programming Arduino bootloaders. But if you plan on doing it more than once a shield is going to save you some headaches as setting up a breadboard each time and then worrying about debugging is a pain...
The project is open sourced and the PCB files can be found on our Github.
The kit itself on our website at www.phenoptix.com
Step 1: The BOM and Tools
The BOM
- PCB - Check out our github
- Pin Headers
- Sockets for 8 pin, 20 pin and 28 pin
- 3 x LEDs
- 3 x Appropriate Resistors
Right so you've got the gear. Now plug in that soldering iron!
Step 2: Stick on the Sockets!
This really is the most boring bit of soldering, think of it as practice. Remember heat the pad and pin and add the solder to the union of the two. You'll want it to look like a lush little cone. Pro tip is to use thin (0.5mm) leaded solder. I started this using some thick lead free solder and you can probably spot the joints where I used it, they're dull and over filled!
Step 3: Insert the LEDs
Once pushed through bend the legs on the LED and resistor back and solder the joints like before. Heat the union of the pad and pin and apply solder. Once soldered you can clip off the legs. Put your finger on the end of the leg as you clip it. That way you won't have to remove it from your eye ball later...
Now for the blue and green, it's your call, the top LED, where we have the green one is going to be your heartbeat LED. The bottom one will flash merrily as the chips are being programmed. Solder these boys in as well as the resistors and clip off the legs, protecting your eyes once more.
Step 4: Solder the ISP Headers
Step 5: Solder the Arduino Headers
Step 6: Add Arduino, Chips and Code!
You can now program Arduino Bootloaders from within the IDE and also the AVR chips listed with AVRDUDE, but I'll explain how to do all that on a less product oriented Instructable.
// this sketch turns the Arduino into a AVRISP
// using the following pins:
// 10: slave reset
// 11: MOSI
// 12: MISO
// 13: SCK
// Put an LED (with resistor) on the following pins:
// 7: Error - Lights up if something goes wrong (use red if that makes sense)
// 8: Programming - In communication with the slave
// 6: Heartbeat - shows the programmer is running (removed, see notes below)
// Optional - Piezo speaker on pin A3
//
// October 2009 by David A. Mellis
// - Added support for the read signature command
//
// February 2009 by Randall Bohn
// - Added support for writing to EEPROM (what took so long?)
// Windows users should consider WinAVR's avrdude instead of the
// avrdude included with Arduino software.
//
// January 2008 by Randall Bohn
// - Thanks to Amplificar for helping me with the STK500 protocol
// - The AVRISP/STK500 (mk I) protocol is used in the arduino bootloader
// - The SPI functions herein were developed for the AVR910_ARD programmer
// - More information at http://code.google.com/p/mega-isp
//
// March 2012 - William Phelps
// modify to work with Arduino IDE 1.0 which has a shorter serial port receive buffer
// getEOP() now gets entire request before avrisp() is called to process it
// Serial.print((char) xxx) changed to Serial.write(xxx)
// uint8_t changed to byte
// added support for Piezo speaker
// moved Pmode LED to A0
// removed "heartbeat" on pin 6, added short blip of ERROR LED instead
// Why is it that PROG_FLASH and PROG_DATA don't actually do anything???
// Tested with Arduino IDE 22 and 1.0
// IDE 22 - 5148 bytes
// IDE 1.0 - 5524 bytes!
// January 2014 - Ben Gray
// Put the heartbeat LED back and switched around the pins a little for the LEDs.
// SLOW SPEED CHIP ERASE AND FUSE BURNING
//
// Enable LOW_SPEED to allow you to erase chips that would fail otherwise,
// for being running with a clock too slow for the programmer.
//
// This allowed me to recover several ATMega328 that had no boot loader and the
// first instruction was to set the clock to the slowest speed. Usually this
// kind of recovery requires high voltage programming, but this trick will do
// just fine.
//
// How to proceed:
// 1. Enable LOW_SPEED, and load it to the programmer.
// 2. Erase and burn the fuses on the target uC. Example for ATMega328:
// arduino-1.0.1/hardware/tools/avrdude -Carduino-1.0.1/hardware/tools/avrdude.conf -patmega328p -cstk500v1 -P /dev/serial/by-id/usb-FTDI_FT232R_USB_UART_A900cf1Q-if00-port0 -b19200 -e -Ulock:w:0x3F:m -Uefuse:w:0x05:m -Uhfuse:w:0xDA:m -Ulfuse:w:0xF7:m
// 3. Comment LOW_SPEED and load it back to the programmer.
// 4. Program the target uC as usual. Example:
// arduino-1.0.1/hardware/tools/avrdude -Carduino-1.0.1/hardware/tools/avrdude.conf -patmega328p -cstk500v1 -P /dev/serial/by-id/usb-FTDI_FT232R_USB_UART_A900cf1Q-if00-port0 -b19200 -Uflash:w:firmware.hex:i
//
// Note 1: EXTRA_SPI_DELAY was added to let you slow down SPI even more. You can
// play with the value if it does not work with the default.
// Note 2: LOW_SPEED will alow you only to erase the chip and burn the fuses! It
// will fail if you try to program the target uC this way!
//#define LOW_SPEED
#ifdef LOW_SPEED
#define EXTRA_SPI_DELAY 125
#else
#define EXTRA_SPI_DELAY 0
#endif
#include "pins_arduino.h" // defines SS,MOSI,MISO,SCK
#define RESET SS
#define LED_ERR 7
#define LED_PMODE 8
#define LED_HB 6
//#define PIEZO A3
#define HWVER 2
#define SWMAJ 1
#define SWMIN 18
// STK Definitions
const byte STK_OK = 0x10;
const byte STK_FAILED = 0x11;
const byte STK_UNKNOWN = 0x12;
const byte STK_INSYNC = 0x14;
const byte STK_NOSYNC = 0x15;
const byte CRC_EOP = 0x20; //ok it is a space...
const byte STK_GET_SYNC = 0x30;
const byte STK_GET_SIGNON = 0x31;
const byte STK_GET_PARM = 0x41;
const byte STK_SET_PARM = 0x42;
const byte STK_SET_PARM_EXT = 0x45;
const byte STK_PMODE_START = 0x50;
const byte STK_PMODE_END = 0x51;
const byte STK_SET_ADDR = 0x55;
const byte STK_UNIVERSAL = 0x56;
const byte STK_PROG_FLASH = 0x60;
const byte STK_PROG_DATA = 0x61;
const byte STK_PROG_PAGE = 0x64;
const byte STK_READ_PAGE = 0x74;
const byte STK_READ_SIGN = 0x75;
//// TONES ==========================================
//// Start by defining the relationship between
//// note, period, & frequency.
//#define c 3830 // 261 Hz
//#define d 3400 // 294 Hz
//#define e 3038 // 329 Hz
//#define f 2864 // 349 Hz
//#define g 2550 // 392 Hz
//#define a 2272 // 440 Hz
//#define b 2028 // 493 Hz
//#define C 1912 // 523 Hz
//void pulse(int pin, int times);
int error=0;
int pmode=0;
// address for reading and writing, set by STK_SET_ADDR command
int _addr;
byte _buffer[256]; // serial port buffer
int pBuffer = 0; // buffer pointer
int iBuffer = 0; // buffer index
byte buff[256]; // temporary buffer
boolean EOP_SEEN = false;
void setup() {
Serial.begin(19200);
// pinMode(PIEZO, OUTPUT);
// beep(1700, 40);
EOP_SEEN = false;
iBuffer = pBuffer = 0;
pinMode(LED_PMODE, OUTPUT);
pulse(LED_PMODE, 2);
pinMode(LED_ERR, OUTPUT);
pulse(LED_ERR, 2);
pinMode(LED_HB, OUTPUT);
pulse(LED_HB, 2);
pinMode(9, OUTPUT);
// setup high freq PWM on pin 9 (timer 1)
// 50% duty cycle -> 8 MHz
OCR1A = 0;
ICR1 = 1;
// OC1A output, fast PWM
TCCR1A = _BV(WGM11) | _BV(COM1A1);
TCCR1B = _BV(WGM13) | _BV(WGM12) | _BV(CS10); // no clock prescale
}
#define beget16(addr) (*addr * 256 + *(addr+1) )
typedef struct param {
byte devicecode;
byte revision;
byte progtype;
byte parmode;
byte polling;
byte selftimed;
byte lockbytes;
byte fusebytes;
int flashpoll;
int eeprompoll;
int pagesize;
int eepromsize;
int flashsize;
}
parameter;
parameter param;
// this provides a heartbeat on pin 6, so you can tell the software is running.
byte hbval=128;
int8_t hbdelta=4;
void heartbeat() {
if (hbval > 192) hbdelta = -hbdelta;
if (hbval < 32) hbdelta = -hbdelta;
if (hbval > 250) hbdelta = -hbdelta;
if (hbval < 10) hbdelta = -hbdelta;
hbval += hbdelta;
analogWrite(LED_HB, hbval);
delay(20);
}
void getEOP() {
int minL = 0;
byte avrch = 0;
byte bl = 0;
while (!EOP_SEEN) {
while (Serial.available()>0) {
byte ch = Serial.read();
_buffer[iBuffer] = ch;
iBuffer = (++iBuffer)%256; // increment and wrap
if (iBuffer == 1) avrch = ch; // save command
if ((avrch == STK_PROG_PAGE) && (iBuffer==3)) {
minL = 256*_buffer[1] + _buffer[2] + 4;
}
if ((iBuffer>minL) && (ch == CRC_EOP)) {
EOP_SEEN = true;
}
}
if (!EOP_SEEN) {
heartbeat(); // light the heartbeat LED
// if (bl == 100) {
// pulse(LED_ERR,1,10); // blink the red LED
// bl = 0;
// }
bl++;
delay(10);
}
}
}
// serialEvent not used so sketch would be compatible with older IDE versions
//void serialEvent() {
// int minL = 0;
// byte avrch = 0;
// while (Serial.available()>0)
// {
// byte ch = Serial.read();
// _buffer[iBuffer] = ch;
// iBuffer = (++iBuffer)%256; // increment and wrap
// if (iBuffer == 1) avrch = ch; // save command
// if ((avrch == STK_PROG_PAGE) && (iBuffer==3)) {
// minL = 256*_buffer[1] + _buffer[2] + 4;
// }
// if ((iBuffer>minL) && (ch == CRC_EOP)) {
// EOP_SEEN = true;
// }
// }
//}
void loop(void) {
// is pmode active?
// if (pmode) digitalWrite(LED_PMODE, HIGH);
// else digitalWrite(LED_PMODE, LOW);
digitalWrite(LED_PMODE, LOW);
// is there an error?
if (error) digitalWrite(LED_ERR, HIGH);
else digitalWrite(LED_ERR, LOW);
getEOP();
// have we received a complete request? (ends with CRC_EOP)
if (EOP_SEEN) {
digitalWrite(LED_PMODE, HIGH);
EOP_SEEN = false;
avrisp();
iBuffer = pBuffer = 0; // restart buffer
}
}
byte getch() {
if (pBuffer == iBuffer) { // spin until data available ???
pulse(LED_ERR, 1);
// beep(1700, 20);
error++;
return -1;
}
byte ch = _buffer[pBuffer]; // get next char
pBuffer = (++pBuffer)%256; // increment and wrap
return ch;
}
void readbytes(int n) {
for (int x = 0; x < n; x++) {
buff[x] = getch();
}
}
//#define PTIME 20
void pulse(int pin, int times, int ptime) {
do {
digitalWrite(pin, HIGH);
delay(ptime);
digitalWrite(pin, LOW);
delay(ptime);
times--;
}
while (times > 0);
}
void pulse(int pin, int times) {
pulse(pin, times, 50);
}
void spi_init() {
byte x;
SPCR = 0x53;
#ifdef LOW_SPEED
SPCR=SPCR|B00000011;
#endif
x=SPSR;
x=SPDR;
}
void spi_wait() {
do {
}
while (!(SPSR & (1 << SPIF)));
}
byte spi_send(byte b) {
byte reply;
#ifdef LOW_SPEED
cli();
CLKPR=B10000000;
CLKPR=B00000011;
sei();
#endif
SPDR=b;
spi_wait();
reply = SPDR;
#ifdef LOW_SPEED
cli();
CLKPR=B10000000;
CLKPR=B00000000;
sei();
#endif
return reply;
}
byte spi_transaction(byte a, byte b, byte c, byte d) {
byte n;
spi_send(a);
n=spi_send(b);
//if (n != a) error = -1;
n=spi_send(c);
return spi_send(d);
}
void replyOK() {
// if (EOP_SEEN == true) {
if (CRC_EOP == getch()) { // EOP should be next char
Serial.write(STK_INSYNC);
Serial.write(STK_OK);
}
else {
pulse(LED_ERR, 2);
Serial.write(STK_NOSYNC);
error++;
}
}
void breply(byte b) {
if (CRC_EOP == getch()) { // EOP should be next char
Serial.write(STK_INSYNC);
Serial.write(b);
Serial.write(STK_OK);
}
else {
Serial.write(STK_NOSYNC);
error++;
}
}
void get_parameter(byte c) {
switch(c) {
case 0x80:
breply(HWVER);
break;
case 0x81:
breply(SWMAJ);
break;
case 0x82:
breply(SWMIN);
break;
case 0x93:
breply('S'); // serial programmer
break;
default:
breply(0);
}
}
void set_parameters() {
// call this after reading paramter packet into buff[]
param.devicecode = buff[0];
param.revision = buff[1];
param.progtype = buff[2];
param.parmode = buff[3];
param.polling = buff[4];
param.selftimed = buff[5];
param.lockbytes = buff[6];
param.fusebytes = buff[7];
param.flashpoll = buff[8];
// ignore buff[9] (= buff[8])
//getch(); // discard second value
// WARNING: not sure about the byte order of the following
// following are 16 bits (big endian)
param.eeprompoll = beget16(&buff[10]);
param.pagesize = beget16(&buff[12]);
param.eepromsize = beget16(&buff[14]);
// 32 bits flashsize (big endian)
param.flashsize = buff[16] * 0x01000000
+ buff[17] * 0x00010000
+ buff[18] * 0x00000100
+ buff[19];
}
void start_pmode() {
spi_init();
// following delays may not work on all targets...
pinMode(RESET, OUTPUT);
digitalWrite(RESET, HIGH);
pinMode(SCK, OUTPUT);
digitalWrite(SCK, LOW);
delay(50+EXTRA_SPI_DELAY);
digitalWrite(RESET, LOW);
delay(50+EXTRA_SPI_DELAY);
pinMode(MISO, INPUT);
pinMode(MOSI, OUTPUT);
spi_transaction(0xAC, 0x53, 0x00, 0x00);
pmode = 1;
}
void end_pmode() {
pinMode(MISO, INPUT);
pinMode(MOSI, INPUT);
pinMode(SCK, INPUT);
pinMode(RESET, INPUT);
pmode = 0;
}
void universal() {
// int w;
byte ch;
// for (w = 0; w < 4; w++) {
// buff[w] = getch();
// }
readbytes(4);
ch = spi_transaction(buff[0], buff[1], buff[2], buff[3]);
breply(ch);
}
void flash(byte hilo, int addr, byte data) {
spi_transaction(0x40+8*hilo, addr>>8 & 0xFF, addr & 0xFF, data);
}
void commit(int addr) {
spi_transaction(0x4C, (addr >> 8) & 0xFF, addr & 0xFF, 0);
}
//#define _current_page(x) (here & 0xFFFFE0)
int current_page(int addr) {
if (param.pagesize == 32) return addr & 0xFFFFFFF0;
if (param.pagesize == 64) return addr & 0xFFFFFFE0;
if (param.pagesize == 128) return addr & 0xFFFFFFC0;
if (param.pagesize == 256) return addr & 0xFFFFFF80;
return addr;
}
byte write_flash(int length) {
if (param.pagesize < 1) {
return STK_FAILED;
}
//if (param.pagesize != 64) return STK_FAILED;
int page = current_page(_addr);
int x = 0;
while (x < length) {
if (page != current_page(_addr)) {
commit(page);
page = current_page(_addr);
}
flash(LOW, _addr, buff[x++]);
flash(HIGH, _addr, buff[x++]);
_addr++;
}
commit(page);
return STK_OK;
}
byte write_eeprom(int length) {
// here is a word address, so we use here*2
// this writes byte-by-byte,
// page writing may be faster (4 bytes at a time)
for (int x = 0; x < length; x++) {
spi_transaction(0xC0, 0x00, _addr*2+x, buff[x]);
delay(45);
}
return STK_OK;
}
void program_page() {
byte result = STK_FAILED;
int length = 256 * getch() + getch();
if (length > 256) {
Serial.write(STK_FAILED);
error++;
return;
}
char memtype = (char)getch();
// for (int x = 0; x < length; x++) {
// buff[x] = getch();
// }
readbytes(length);
if (CRC_EOP == getch()) {
Serial.write(STK_INSYNC);
switch (memtype) {
case 'E':
result = (byte)write_eeprom(length);
break;
case 'F':
result = (byte)write_flash(length);
break;
}
Serial.write(result);
if (result != STK_OK) {
error++;
}
}
else {
Serial.write(STK_NOSYNC);
error++;
}
}
byte flash_read(byte hilo, int addr) {
return spi_transaction(0x20 + hilo * 8,
(addr >> 8) & 0xFF,
addr & 0xFF,
0);
}
char flash_read_page(int length) {
for (int x = 0; x < length; x+=2) {
byte low = flash_read(LOW, _addr);
Serial.write( low);
byte high = flash_read(HIGH, _addr);
Serial.write( high);
_addr++;
}
return STK_OK;
}
char eeprom_read_page(int length) {
// here again we have a word address
for (int x = 0; x < length; x++) {
byte ee = spi_transaction(0xA0, 0x00, _addr*2+x, 0xFF);
Serial.write( ee);
}
return STK_OK;
}
void read_page() {
byte result = (byte)STK_FAILED;
int length = 256 * getch() + getch();
char memtype = getch();
if (CRC_EOP != getch()) {
Serial.write(STK_NOSYNC);
return;
}
Serial.write(STK_INSYNC);
if (memtype == 'F') result = flash_read_page(length);
if (memtype == 'E') result = eeprom_read_page(length);
Serial.write(result);
return;
}
void read_signature() {
if (CRC_EOP != getch()) {
Serial.write(STK_NOSYNC);
error++;
return;
}
Serial.write(STK_INSYNC);
byte high = spi_transaction(0x30, 0x00, 0x00, 0x00);
Serial.write(high);
byte middle = spi_transaction(0x30, 0x00, 0x01, 0x00);
Serial.write(middle);
byte low = spi_transaction(0x30, 0x00, 0x02, 0x00);
Serial.write(low);
Serial.write(STK_OK);
}
//////////////////////////////////////////
//////////////////////////////////////////
////////////////////////////////////
////////////////////////////////////
int avrisp() {
byte data, low, high;
byte avrch = getch();
switch (avrch) {
case STK_GET_SYNC: // get in sync
replyOK();
break;
case STK_GET_SIGNON: // get sign on
if (getch() == CRC_EOP) {
Serial.write(STK_INSYNC);
Serial.write("AVR ISP");
Serial.write(STK_OK);
}
break;
case STK_GET_PARM: // 0x41
get_parameter(getch());
break;
case STK_SET_PARM: // 0x42
readbytes(20);
set_parameters();
replyOK();
break;
case STK_SET_PARM_EXT: // extended parameters - ignore for now
readbytes(5);
replyOK();
break;
case STK_PMODE_START: // 0x50
// beep(2272, 20);
start_pmode();
replyOK();
break;
case STK_PMODE_END: //0x51
// beep(1912, 50);
error=0;
end_pmode();
replyOK();
break;
case STK_SET_ADDR: // 0x55
_addr = getch() + 256 * getch();
replyOK();
break;
case STK_UNIVERSAL: //UNIVERSAL 0x56
universal();
break;
case STK_PROG_FLASH: //STK_PROG_FLASH ???
low = getch();
high = getch();
replyOK();
break;
case STK_PROG_DATA: //STK_PROG_DATA ???
data = getch();
replyOK();
break;
case STK_PROG_PAGE: //STK_PROG_PAGE
// beep(1912, 20);
program_page();
break;
case STK_READ_PAGE: //STK_READ_PAGE
read_page();
break;
case STK_READ_SIGN: //STK_READ_SIGN
read_signature();
break;
// expecting a command, not CRC_EOP
// this is how we can get back in sync
case CRC_EOP:
Serial.write(STK_NOSYNC);
break;
// anything else we will return STK_UNKNOWN
default:
if (CRC_EOP == getch())
Serial.write(STK_UNKNOWN);
else
Serial.write(STK_NOSYNC);
}
}
// beep without using PWM
//void beep(int tone, long duration){
// long elapsed = 0;
// while (elapsed < (duration * 10000)) {
// digitalWrite(PIEZO, HIGH);
// delayMicroseconds(tone / 2);
// digitalWrite(PIEZO, LOW);
// delayMicroseconds(tone / 2);
// Keep track of how long we pulsed
// elapsed += tone;
// }
//}