ISPnub - Stand-alone AVR In-System-Programmer Module

ISBnub ISPnub is a simple to use stand alone programmer intended for flashing AVR controllers in the field directly in the target system or during production. The module has only one button and two leds as user interface.



Before ISPnub can flash controllers, it has to be flashed itself with the programming instructions.

1. Preparing: Load programming instructions into ISPnub

A programming script defines with simple commands the steps for the programming process. This method is very flexible and can be adopted for almost all AVR controllers. See the ISPnub Programming Script Manual. The sequences for serial programming are described in the datasheet of the specific AVR microcontroller. Here is a example of a simple programming process ("test.ispnub"):
CONNECT 2000000                           ; connect with SCK = 2 MHz 
SPIVERIFY 0x30, 0x00, 0x00, 0x00, 0x1E    ; check signature byte 0x00 (0x1E = manufactured by Atmel)
SPIVERIFY 0x30, 0x00, 0x01, 0x00, 0x93    ; check signature byte 0x01 (0x93 = 8KB Flash memory)
SPIVERIFY 0x30, 0x00, 0x02, 0x00, 0x07    ; check signature byte 0x02 (0x07 = ATmega8 device)
SPIWRITE  0xAC, 0x80, 0x00, 0x00          ; chip erase
WAIT 2                                    ; wait 20 ms
FLASH ../test/main.hex, 0, 64             ; flash given hex file starting at flash address 0 with pagesize 64
DISCONNECT                                ; disconnect SPI
DECCOUNTER 10                             ; allow 10 programming cycles
Clock switching and EEPROM writes can also be realized with ISPnub. Here is an enhanced example which uses such features: example.ispnub.

The hex file for the ISPnub is generated with a Java tool (see download section):
java -jar ISPnubCreator.jar test.ispnub ispnub.hex
Now the "ispnub.hex" can be flashed with your favorite programmer (e.g. USBasp) into the ISPnub module. Set the jumper on the ISPnub while programming (and don't forget to remove the jumper after flashing!). Here is an example which uses avrdude and USBasp:
avrdude -c usbasp -p atmega1284p -U hfuse:w:0xD9:m -U lfuse:w:0xE2:m -U flash:w:ispnub.hex -U lock:w:0x3C:m
... ISPnub is now ready for stand-alone flashing.

Video hosted on Youtube:

2. Flashing: Program target controllers

Using the prepared ISPnub is very easy. Just follow these steps:


To use ISPnub, just one tool is needed: ISPnubCreator. It generates from programming instructions a hex file for the ISPnub. The tool is written in Java and can be used on many different platforms (Windows, Linux, Mac, ..).

ISPnubCreator_v1.4.jar (2020-12-18; 10,7 kB) Minor fix on LED pin handling
ISPnubCreator_v1.3.jar (2014-09-01; 9,9 kB) Support for target controller with flash up to 256kBytes
ISPnubCreator_v1.2.jar (2014-04-10; 9,9 kB) Skip blocks with 0xff, added EEPROM command
ISPnubCreator_v1.1.jar (2014-04-03; 8,3 kB)
ISPnubCreator_v1.0.jar (2013-06-14; 14,7 kB)

The source code is hosted on Github: ISPnubCreator and ISPnub firmware.



The main component of ISPnub is an ATmega1284P. ISPnub schematic


ISPnub PCB (3x)
ISPnub: 3xPCB
€ 12,90
incl. 19% VAT excl. € 4 shipping

Order ISPnub-PCBs now!
C1, C2100nX7R-5 100N80-C0805C104K5R
IC1ATmega1284P-AUATMEGA 1284P-AU556-ATMEGA1284P-AU
JP12pol 2,54mmMPE 087-1-002571-826936-2
LED1LED0805 redSMD-LED 0805 RT604-APT1608SURC
LED2LED0805 greenSMD-LED 0805 GN604-APT2012SGC
R110k1/4W 10K603-SR0805JR-0710KL
R2, R31k1/4W 1,0K71-CRCW0805-1.0K-E3
S1SwitchTASTER 9314693-1301.9314
X110polWSL 10W517-N2510-5002RB
M1JumperJUMPER 2,54GL SW517-9691020000DA
Please tell me about your ISPnub project!

ISPnub case
   3d printed case for ISPnub.
ISPnub case on Shapeways

by MxChristensen (08/2020)
ISPnub with USB connector
   Es-tronics built his own version of ISPnub. He added an USB connector for powersupply during programming of the ATmaga1284p and packed the board into a 3d printed enclosure.

by es-tronics (12/2020)
Testadapter with integrated ISPnub
   Wolfgang has developed a programming and test adapter for a relay board. The target circuit is contacted via test pins. Besides the ISPnub functionality for programming a console and a test program was implemented on the ATmega.

by Wolfgang K. (02/2021)
Testadapter with integrated ISPnub
   This version was designed by Bernhard. It is prepared for use with pogo pins.

by Bernhard R. (11/2021)
ISPnub case
   3d printed enclosure for ISPnub.
ISPnub enclosure on Thingiverse

by semiversus (02/2022)


Regarding ISPnub:
ISPnub Programming Script Manual
Top view of ISPnub pcb and parts
de Reichelt Bauteil Warenkorb zu ISPnub v1.1 (part list for ISPnub)

Other AVR programmers with stand-alone function:
en Arduino Stand-alone Programmer Kit

Standalone programmer for other microcontrollers:
en PicKit Programmer-to-go (for Microchip PICs)