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

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.

Features

No external power supply needed. Uses voltage provided by target (1.8V to 5.5V).
Programming counter. Limit possible programming cycles. After allowed cycles, no further programming is possible (module has to be erased/reprogrammed).
One-button-programming: connect - push button - wait for red led off.
Simple LED schema:
- green on = ok
- green blink = counter expired
- red on = programming
- red blink = error
Define programming with simple script. Script converter generates HEX file for module.
Load module with any ISP programmer which supports ATmega1284p
120kB memory space for programming data

Usage

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
END

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:

Connect ISPnub to target (ISPnub is powered from target!)
Green LED is on, if ISPnub is ready
Press button -> programming starts. While programming, green and red LEDs are on.
On success: green LED is on, red off.
On error: red LED blinks. Press button to start new programming cycle

Download

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.

Hardware

Schematic

The main component of ISPnub is an ATmega1284P. ISPnub schematic

Partlist

ISPnub PCB (3x)

€ 12,90

incl. 19% VAT excl. € 4 shipping

Order ISPnub-PCBs now!

Partnumber	Value	Reichelt	Mouser
C1, C2	100n	X7R-5 100N	80-C0805C104K5R
IC1	ATmega1284P-AU	ATMEGA 1284P-AU	556-ATMEGA1284P-AU
JP1	2pol 2,54mm	MPE 087-1-002	571-826936-2
LED1	LED0805 red	SMD-LED 0805 RT	604-APT1608SURC
LED2	LED0805 green	SMD-LED 0805 GN	604-APT2012SGC
R1	10k	1/4W 10K	603-SR0805JR-0710KL
R2, R3	1k	1/4W 1,0K	71-CRCW0805-1.0K-E3
S1	Switch	TASTER 9314	693-1301.9314
X1	10pol	WSL 10W	517-N2510-5002RB
M1	Jumper	JUMPER 2,54GL SW	517-9691020000DA

Gallery

Please tell me about your ISPnub project!

		3d printed case for ISPnub. ISPnub case on Shapeways by MxChristensen (08/2020)
		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)
		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)
		This version was designed by Bernhard. It is prepared for use with pogo pins. by Bernhard R. (11/2021)
		3d printed enclosure for ISPnub. ISPnub enclosure on Thingiverse by semiversus (02/2022)

Links

Regarding ISPnub:
ISPnub Programming Script Manual
Top view of ISPnub pcb and parts

Reichelt Bauteil Warenkorb zu ISPnub v1.1 (part list for ISPnub)

Other AVR programmers with stand-alone function:

AVR-ISP500-TINY

Arduino Stand-alone Programmer Kit

Standalone programmer for other microcontrollers:

PicKit Programmer-to-go (for Microchip PICs)