Flash cart(ridge)

(Kevin) #184

My personal feeling on this based on no scientific evidence at all is that the eeprom chip will run just fine at system voltage. This all reminds me of the discussion about not running the mcu at 16mhz because its slightly out of spec.


(Kim) #185

Hi i am a newbie here. I am stuck in burning the cathy3k bootloader to my homemade arduboy. Do i need another programmer like the USBasp to do that? I have the level shifter and the flash memory but it does not seem to work. Please help.



For me, I do use USBasp to program the Cathy 3k to my homemade Arduboy. Not sure if you are using the original Arduboy or a homemade one. I have summarized how I setup the homemade package, the cathy3K and the serial flash for my homemade Arduboy in this video.

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You can not upload the bootloader as a normal program. You need an ICSP programmer for that. An USBasp is a popular programmer but you can also use an Arduino UNO if you have one around.

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(Kevin) #188

You can use any kind of Arduino as an ICSP, the pins are just different.



Updated the Cathy3K bootloader with a progress bar:

You can download it from here:

4-bit displays don’t have the progressbar yet due to size constraints.


(Nao) #190

Thank you for updating Cathy 3k.
I tried it a while ago, it worked well,
A progress bar appeared :smiley:.

By the way, the sample csv, “flashcart-index.csv” of “Pyhon utility” seems to be left out of the update.

(Perhaps each line requires two more delimiters?)

Sample csv, “flashcart-index.csv”

1;Action Games;category-screens\Action.png;

Maybe it’s like
0;Bootloader title;arduboyloader.png;;;
1;Team ARG games title;team-arg-games\teamarglogo.png;;;



Thanks for pointing that out. I will fix that.

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So with others hooking stuff to the expansion port. I decided to have a go at it myself too.

Arduboy controlling neopixels :smiley:


(Nao) #193

Great work!:smiley:

I also found another hooking stuff.
That’s the Small IIC keypad for Arduboy with FlashCart Expansion Slot.

The other day, a small qwerty keypad, “CardKB” was launched as one of the peripherals for the “M5Stack”.
This is a very small IIC keyboard, equipped with MEGA 328P as a controller.

Since the IIC is pulled out to the Arduboy Flashcart expansion slot, “CardKB” can be used simply by connecting it.
Usage is simple. It only requests one byte to the IIC address 0x5F.
For those who want to easily connect a keyboard to Arduboy, CardKB may be an item worth considering.
(However, the key press is not so good and is not suitable for long time typing.)

And there is a great man, “TAMAKICHI” who developed firmware to be able to use CardKB as a PS2 keyboard.
This allows CardKB to connect to the old PCs.
(It is possible to connect to Raspberry Pi etc via PS2-USB converter.)


(Kevin) #194

the dongles

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(Pharap) #195

Where are the neopixels from? Are they individually controllable and can they be moved?

I have the sudden urge to build myself a stargate…
(Though it wouldn’t be as cool as this guy’s stargate.)


(Kevin) #196

Adafuruit coined the term neopixel for WS2812B and similar addressable LED’s when she was one of the first retail distributors to sell them.

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(Simon) #197

Search for WS2812, WS8218B or 5050 RGB LEDs. As @bateske indicated Neopixels is Ardufruit’s ‘brand’ name for them.

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Sorry for the late reply. The term ‘neopixel’ is like @bateske said. The ones I have are WS2812 (compatible) RGB LEDs. Unlike regular RGB LEDs these have a little serial controller onboard. The color and brightness is set by by sending a 24-bit RGB value over a single wire at a speed of 800KHz. These RGB LEDs can be easily cascaded. Like the ring I have, long strings or small matrices.

I’ve considered adding them to my LEGO Dimensions portal :smiley:

That stargate in that video is amazing.



Made another expansion. Arduboy DoubleScreen :grin:

(DonkeyKong mockup screens by @Ken_Cheung)

(Simon) #200

That’s fantastic ! Are you using a screen buffer and, if so, is it using memory from the Arduboy itself? I can imagine there is nothing left over!


(Scott) #201

Most games clear the buffer then render each frame entirely. In this case, you could get away with a single buffer.

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As @MLXXXp said. I’m using the same display buffer twice. I’m rendering one frame, display it and then render the next and display it. Updating each display takes about ~1.2msec so theres about ~7.1msec rendering time per frame.


(Ken Cheung) #203

WOW, very good ! Can make more display on Arduboy!?