The Cart Micro IEC has also gotten a few tweaks.

Connectors

I have changed to a thruhole directly soldered DIN male connector. The previous versions has connected the DIN male part with thin wires.

A bit tight as can be seen because of the 1.5mm pins. Especially for the 5 pin DIN connector the pads is very tight. That is why I have the peculiar pad shapes. Most of the wetting will be on one side of the pins.

LEDs

I change the thruhole green LEDs to side firing SMT mounted Green/Yellow LEDs. Green for connected and yellow when transmitting/reading.

IEC Drivers

I have also changed the driver for the IEC ATN/CLK/DATA signals from a 74LS06 buffer to a discrete solution around MOSFET NX3008 in SOT323 package.

All for cost.

WiFi

I have also changed to the discrete WiFi solution that I have on Cart Jr II. It is the famous ESP 8266 from Espresif in China. Not at all my favourite chip, but it is dirt cheap. I am also using the version with built in flash memory, called ESP 8285.