Flashcart upload and play problem

Does anyone know of a video explaining how to use @Mr.Blinky’s Python Utilities to upload .hex files and how to write to flashcart.

Hi Paul welcome to the community. I didn’t make any how to vids yet. Theres some basic info on github on how to install and use the uploader and an example flashcart.

Writing games to the flashcart is a currently a two step progress.

  • 1st you build an image file with the games hex files and menu screens using the flashcart-builder.py script
  • 2nd the flashimage is written to flash using the flashcart-writer.py script

The builder tool requires a .csv file with each row containing a list index, relative links to a title image and a hex file. There must also be a sub directory containing the images and hex files. It’s best to have an look at the example flashcart

It’s best to run these scripts from the command line (in the beginning) so errors can be tracked more easily.



Hi Mr Blinky,

Thank you so much for the reply.

I have managed to write to the flashcart but how do I access the games.

Please see attached photo.



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You need to update the bootloader with latest cathy3k bootloader

It is easiest done from within the Arduino IDE when the Homemade package is installed.

The bootloader can not be uploaded like a normal sketch but requires an ISP (In system programming) programmer like an USBasp or an Arduino that functions as ISP.

When I press the reset button the USB logo appears and then after a few seconds the last game starts.

Is this the correct bootloader?

That’s an older version but should be ok. Does your image file has a loader screen in list/group 0?

How do I update the bootloader in Arduino IDE?

From the tools menu select Arduboy board, cathy3K bootloader, your programmer and click Burn bootloader.


Note if you use a non Leonardo based board or using SDA pin as flashchipselect. Select Homemade Arduboy instead, cathy 3k as bootloader, the board your using, the flash select pin,display, your programmer and click Burn bootloader.

I have Arduboy Homemade package Version 1.2.6 installed and I still get the USB logo. What am I doing wrong?

The screenshot you’ve posted shows that the JEDEC ID was successfully read from your flash chip so I can only imagine there is a problem with your flash image file.

As I asked before, did you include a loader screen in group / list 0 in your csv file?

It’s hard to tell what is wrong without knowing seeing your csv / flash image file.

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Since this is all new to me I have used the games-image.bin file provided by Billy Cheung because I would imaginge that there are no errors with this file.

I have attached the files for your perusal and comments.

(Attachment games.csv is missing)

(Attachment games-image.bin is missing)

Looks like your attachments are missing. try appending .pdf to them so they get accepted as uploads. Or you may just post the links if they are publicly available.


Nevermind, I found them on github


I’ve tested the game-image and it works alright. So it looks to be an hardware issue.

After switching on and pressing reset, does loader screen appear? Does the screen change when pressing left/right buttons?

You may need to check your Vcc and GND wiring to the flashchip and put a 100nF capacitor across them.

If that doesn’t help you may need to give more details about your hardware supported by detailed pictures.

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Photos attached of my modified Arduboy with your flashcart. I get the USB logo when I press the reset button. The red blue and green led’s flash in sequence.

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Oh nice. Now I also know how Blinky looks on a green PCB :slight_smile:

Try uploading this test sketch

After uploading press A to see the flashchip status. If the value changes you may have a bad connection somewhere. A screenshot of the status may be usefull too.

Pressing B will show flash contents as 1K animation. When no animation is loaded yet with the writer tool the screen should stay white. If it flickers there’s a bad connection.

you can write the default animation file to flash using the following command from the command prompt:

[path]\flashcart-writer.py -d [path]\thedoors-frames.bin

Where [path] is the full path to the relevant files. To save typing them you can drag and drop the files to command prompt. After the write has completed you should see a cool animation with the B option


There’s probably a poor solder joint. Apply some solder flux to the pads and reheat them


What is the exact part number of the flashchip you use?

Please can you supply the missing file.

Flashchip - WINBOND 25Q128JVSQ

The file is right there in the repo:

Download cart.h and cart.cpp and then make sure your document tree looks like:

|   |---flashcart-test.ino
|   |---src
|       |---cart.h
|       \---cart.cpp
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They’re on github. Note you don’t need to copy and paste the sketch. You can view it on github and then right click the raw button and choose save. Here are the links for your convenience:

(right click and choose save as)




make sure you put the cart files in a subfolder in the sketch folder called src

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Thanks for the files, when I press B I get the stable white screen as I have no animation loaded yet.

Strange. Everything looks okay. Could you try uploading the animation as described above?