Arachnid with external EEPROM

[ClippyTheDiode]

Here is my Arachnid build with an external EEPROM "Cart".

I used a 8 pin board edge connector I found on Amazon. This allows the cart to be inserted in either direction and still operate. I also changed R5 from 3.3V to GND. This allows the cart to toggle the FV-1 pin 13 on insertion. This means that when no cart is present it defaults to the internal FV-1 programs. I can then plug a cart in and it will automatically load the programs from the cart. So I can hotswap the carts.

 

[Paradox916]

Very cool.

 

[Cybercow]

Slick! The only question I have is regarding the positioning of the edge-card insertion point. Could it get squashed when the pedal is stomped? A miscalculated foot-stomp seems potentially devastating.

 

[ClippyTheDiode]

Slick! The only question I have is regarding the positioning of the edge-card insertion point. Could it get squashed when the pedal is stomped? A miscalculated foot-stomp seems potentially devastating.

When the switch is fully pressed it is still about 5mm above the board edge. So if you were really stomping on it you may hit the pcb. The socket is just hot glued in from the backside, so hopefully that would give way first. I wanted to leave enough cart sticking up to make it easy to remove without tools. It looks like I can also make the pcb a little shorter on the next revision. Ultimately the location was a comprimise, but I find myself operating this pedal with my hands (knobs, and selctor) more than toggling with my foot. But I am just playing in my livingroom, not gigging.

 

[Harry Klippton]

I would absolutely get that lil socket full of dirt. Cool idea though

 

[ClippyTheDiode]

I would absolutely get that lil socket full of dirt. Cool idea though

My pedalboard is 10% little bits of marijuana and cat hair. So we will see how this goes.

 

[Cybercow]

When the switch is fully pressed it is still about 5mm above the board edge. So if you were really stomping on it you may hit the pcb. The socket is just hot glued in from the backside, so hopefully that would give way first. I wanted to leave enough cart sticking up to make it easy to remove without tools. It looks like I can also make the pcb a little shorter on the next revision. Ultimately the location was a comprimise, but I find myself operating this pedal with my hands (knobs, and selctor) more than toggling with my foot. But I am just playing in my livingroom, not gigging.

Fair enough on all that. Still, my reservations aside, that is a slick trick you pulled off there.

Do you have a link for the Amazon 8-pin edge connector?

 

[ClippyTheDiode]

Thanks!

Here is a link to the edge connectors:

Amazon.com

Here is a link to the PCB at OSHPark:

OSH Park ~

oshpark.com

The EEPROM footprint is SOIC-8, the capacitor is 0.1uF 0805.

 

[Cybercow]

Thanks!

Here is a link to the edge connectors:

Amazon.com

Here is a link to the PCB at OSHPark:

OSH Park ~

oshpark.com

The EEPROM footprint is SOIC-8, the capacitor is 0.1uF 0805.

Thank you!

 

[Locrian99]

Wow I’ve sat around thinking about this multiple times looked up parts and never really went any where with it. Absolutely awesome.

 

[ClippyTheDiode]

Wow I’ve sat around thinking about this multiple times looked up parts and never really went any where with it. Absolutely awesome.

Thanks, I'm really happy with how it came out.

 

[Paradox916]

This has to be one of the more creative mods I have seen in a while makes me happy to see someone thinking outside the box. This is the kind of thing that inspire me to do crazy stuff.

 

[ClippyTheDiode]

This has to be one of the more creative mods I have seen in a while makes me happy to see someone thinking outside the box. This is the kind of thing that inspire me to do crazy stuff.

Thank you. There is a lot of inspiration on this forum. Happy to provide some as well.

 

[ClippyTheDiode]

Got more parts to make more carts!
My EEPROMs finally got here. I had been robbing them off of adafruit boards I had laying around.
I also drew up a "dev" version of the cart with a ribbon cable header.
The dev cart makes development easier when you want to test on the actual hardware.
Now I don't have to swap the carts every time I want to update the program.
I can just re-flash the dev cart, then flip the program select switch to load the new program.
Now I just need more colors of heatshrink.

 

[p_wats]

Wow. That's awesome---very inspiring! Nice job