#070 Programming an ATtiny With ArduinoISP

Programming an ATTINY85-20PU on a breadboard with Arduino ISP

Here’s a quick video of it in action:

Notes

The objective here is to setup an ATTINY85-20PU chip on a breadboard, and program it using an Arduino operating as an in-system programmer.

Adding ATiny support for Arduino IDE

I’m running Arduino 1.6.1 (MacOSX), so I first needed to add ATiny support for Arduino IDE 1.6.x. I always prefer to clone rather than download zips so I’m able to work on the source if necessary. In these steps ${sketchbook_folder} refers to my actual sketchbook folder location.

git clone git@github.com:damellis/attiny.git
cd attiny
git checkout -b ide-1.6.x origin/ide-1.6.x
mkdir ${sketchbook_folder}/hardware
cp -R attiny ${sketchbook_folder}/hardware

After restarting Arduino, I now have new Tools menu options.

Setup the Arduino ISP

Setup the Arduino ISP. Note in this case I’m using an Arduino Uno as the programmer:

Select Tools > Board > Arduino Uno
Select Tools > Port > (correct port for Arduino Uno)
Upload Examples/ArduinoISP sketch to Arduino Uno
Select Programmer > Arduino as ISP

Selecting ATtiny options

I went with the basics:

Tools > Board > ATtiny
Tools > Processor > ATtiny85
Tools > Clock > 1MHz (internal)

Burning the Bootloader

Depending on the state of the chip, this may not be necessary. But if in doubt, burn it again:

Select Tools > Burn Bootloader

Uploading a Sketch

I’m testing with TinyBlink which runs LEDs on digital pins 0 and 1.

Open desired sketch
Select File > Upload Using Programmer (or shift-click the normal upload icon)

Crickey, it works.

How Fast is the Clock?

The ATtiny85 can use an external clock, but by default it uses an internal oscillator. The internal oscillator runs at 8 MHz, prescaled down to 1 MHz by default.

The clock settings are in the fuses. I used avrdude to read the settings:

$ avrdude -c stk500v1 -p attiny85 -P /dev/cu.usbmodem14521 -b 19200 -U lfuse:r:-:i

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.05s

avrdude: Device signature = 0x1e930b (probably t85)
avrdude: reading lfuse memory:

Reading | ################################################## | 100% 0.02s

avrdude: writing output file "<stdout>"
:01000000629D
:00000001FF

avrdude: safemode: Fuses OK (E:FF, H:DF, L:62)

avrdude done.  Thank you.

The engbedded fusecalc site is invaluable for decoding or calculating fuses values.

It confirms that E:FF, H:DF, L:62 are factory defaults: 8 MHz internal oscillator with CKDIV8 prescaler: so it is running at 1 MHz.

Programming with avrdude

The Arduino IDE now includes the ability to export the compiled binary. This option, found in the “Sketch” menu produces TinyBlink.ino.tiny8.hex from the TinyBlink source.

export_compiled_binary

avrdude can then be used to directly upload the hex file via the Arduino ISP:

$ avrdude -v -c stk500v1 -p attiny85 -P /dev/cu.usbmodem14521 -b 19200 -U flash:w:../TinyBlink/TinyBlink.ino.tiny8.hex:i

avrdude: Version 6.3, compiled on Sep 21 2018 at 19:09:46
         Copyright (c) 2000-2005 Brian Dean, http://www.bdmicro.com/
         Copyright (c) 2007-2014 Joerg Wunsch

         System wide configuration file is "/usr/local/Cellar/avrdude/6.3_1/etc/avrdude.conf"
         User configuration file is "/Users/paulgallagher/.avrduderc"
         User configuration file does not exist or is not a regular file, skipping

         Using Port                    : /dev/cu.usbmodem14521
         Using Programmer              : stk500v1
         Overriding Baud Rate          : 19200
         AVR Part                      : ATtiny85
         Chip Erase delay              : 4500 us
         PAGEL                         : P00
         BS2                           : P00
         RESET disposition             : possible i/o
         RETRY pulse                   : SCK
         serial program mode           : yes
         parallel program mode         : yes
         Timeout                       : 200
         StabDelay                     : 100
         CmdexeDelay                   : 25
         SyncLoops                     : 32
         ByteDelay                     : 0
         PollIndex                     : 3
         PollValue                     : 0x53
         Memory Detail                 :

                                  Block Poll               Page                       Polled
           Memory Type Mode Delay Size  Indx Paged  Size   Size #Pages MinW  MaxW   ReadBack
           ----------- ---- ----- ----- ---- ------ ------ ---- ------ ----- ----- ---------
           eeprom        65     6     4    0 no        512    4      0  4000  4500 0xff 0xff
           flash         65     6    32    0 yes      8192   64    128  4500  4500 0xff 0xff
           signature      0     0     0    0 no          3    0      0     0     0 0x00 0x00
           lock           0     0     0    0 no          1    0      0  9000  9000 0x00 0x00
           lfuse          0     0     0    0 no          1    0      0  9000  9000 0x00 0x00
           hfuse          0     0     0    0 no          1    0      0  9000  9000 0x00 0x00
           efuse          0     0     0    0 no          1    0      0  9000  9000 0x00 0x00
           calibration    0     0     0    0 no          1    0      0     0     0 0x00 0x00

         Programmer Type : STK500
         Description     : Atmel STK500 Version 1.x firmware
         Hardware Version: 2
         Firmware Version: 1.18
         Topcard         : Unknown
         Vtarget         : 0.0 V
         Varef           : 0.0 V
         Oscillator      : Off
         SCK period      : 0.1 us

avrdude: AVR device initialized and ready to accept instructions

Reading | ################################################## | 100% 0.02s

avrdude: Device signature = 0x1e930b (probably t85)
avrdude: safemode: hfuse reads as DF
avrdude: safemode: efuse reads as FF
avrdude: NOTE: "flash" memory has been specified, an erase cycle will be performed
         To disable this feature, specify the -D option.
avrdude: erasing chip
avrdude: reading input file "../TinyBlink/TinyBlink.ino.tiny8.hex"
avrdude: writing flash (676 bytes):

Writing | ################################################## | 100% 0.99s

avrdude: 676 bytes of flash written
avrdude: verifying flash memory against ../TinyBlink/TinyBlink.ino.tiny8.hex:
avrdude: load data flash data from input file ../TinyBlink/TinyBlink.ino.tiny8.hex:
avrdude: input file ../TinyBlink/TinyBlink.ino.tiny8.hex contains 676 bytes
avrdude: reading on-chip flash data:

Reading | ################################################## | 100% 0.50s

avrdude: verifying ...
avrdude: 676 bytes of flash verified

avrdude: safemode: hfuse reads as DF
avrdude: safemode: efuse reads as FF
avrdude: safemode: Fuses OK (E:FF, H:DF, L:62)

avrdude done.  Thank you.

Construction

The Breadboard

The Schematic

Build

NB: in the breadboard, pins 5 and 6 are wired LEDs. These are for a test scketch and not required for programming (but neither do they interfere with buring the bootloader and uploading a sketch).

Credits and References

LEAP#071 TinyBlink - a simple ATtiny test sketch
LEAP#253 ProgrammingShield - a programming shield version of this project
ATtiny85 datasheet
ATtiny microcontroller support for the Arduino IDE
Programming an ATtiny w/ Arduino 1.6 (or 1.0)
Programming an ATtiny with Arduino ISP
engbedded fusecalc
Tiny AVR Programmer Hookup Guide

Project Notes