Datasheet

Figure 18: Required wiring between the console expansion connector and the MCU. Refer to figure 5 for
a description of the expansion connector.
Figure 19: Presto! The three extra wires carry the serial line signals TXD, RXD and GND at 3.3V
signal levels. Using shorter wires, the ATtiny25/45/85 MCU can be safely tucked away in the small
bay just below the console expansion connector. The length of the serial line wires is not critical — wire
lengths of more than 1m have been used without any signs of trouble. Regarding serial line voltage levels,
please note the caution on page 2 of this document.
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