ECI mod for AVGCARTs that don't have ECI connector preinstalled

Common

After soldering the connector, please check neighboring pin pairs for shorts

You need firmware 0023 or newer for extram functionality

To enable extram, use CTRL-SHIFT-M (setting is persisted to SD card), CTRL-M to disable

Newer PCBs

Just solder 9pin 90deg 1.25mm pitch "JST" connector and cut opening in the shell

Shorter ECI cable (~7cm) is sufficient

Older PCBs

Longer ECI cable (~10cm) is needed since part of the cable is inside of the cart

Bonus mod for older PCBs

Older PCBs have ground on the rectangular pin as opposed to 5V on the newer ones. This doesn't matter for ECI cable since it doesn't use it (it uses 5V from ECI port). The change was done to support PBI cable (PBI on 800XL usually doesn't have 5V connected).

To future-proof your cart, you can disconnect ground from that pin (it's harder to do after installing the connector). You can either cut those three short traces that connect it to ground plane or bend the leg of the connector before installing it (caution, it's easy to break it so be gentle, modifying PCB is recommended since it's safer).

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