DIY controller hat for pi running FPP V7

[ajp]

Hi,
I would like to make my own controller hat for a pi. It seems with the new FPP V7 in DPi mode, i only need level converters on the gpio pins. Is this right? I seem to understand you need some sort of 'license' or 'eeprom' from falcon for it to work in FPP?

 

[Skymaster]

Correct. The hats for Beaglebone and Raspberry Pi's are not much more than level shifters. Having a physical EEPROM (at24c256) to store the license and pinout configuration is worthwhile.

The license itself is either paid or free, you should be able to get a free one being a DIY cape. There are details in the FAQ in the Falconplayer shop

 

[ajp]

I have applied to join falcon christmas, but it hasn't been approved yet. In the meantime, I am trying to understand the details of designing my own cape.
With FPP V7 (or 6) on the pi in DPipixel mode, it seems there can be up to 24 outputs. Is it stated somewhere if there is any preference for which ones to use for less (say 8, 16) output capes? Do new capes need EEPROM to work with FPP V7, or can the 'virtual' eeprom be used for licensing?

 

[Skymaster]

Virtual can be used for licensing but then you need to follow the pinout of the Cape for which EEPROM you install to the filesystem, and then manage it as that particular Cape with FPP and xLights.

If you custom design your own pinout, you'll need to create your own EEPROM, and controller definition in xLights etc.

Is there a reason to design your own from scratch, rather than purchase a pre-existing one, or use one of the current open source designs?

 

[ajp]

I am an electronics engineer, and having a cape that suits my system is a bit of a challenge, so if I can I want to make my own. Most of the ones for purchase (except from Smartalec, and some of the Hanson stuff) seem overkill to drive a bunch of WS281x LEDs. Also, there doesn't seem to be much yet for a Pi in DPipixel mode

 

[ajp]

Found this, which seems to be the best buy

Pi Cape 8P by BWinter on Tindie

DIY Raspberry Pi Cape for WS281x LEDs, 8-Port, DPIPixels

www.tindie.com

 

[darylc]

I am an electronics engineer, and having a cape that suits my system is a bit of a challenge, so if I can I want to make my own. Most of the ones for purchase (except from Smartalec, and some of the Hanson stuff) seem overkill to drive a bunch of WS281x LEDs. Also, there doesn't seem to be much yet for a Pi in DPipixel mode

DPI mode is not very widely used, and in my view unproven so far.