SSD1306 . . . . X X X . X X . . . . . . .
SSD1351 . . . . X X X X X . . . . . . . .
MCP121 . . . . . . . . . . . . . . X . .
+ PN532 [3] . . . . . . . . . . . . . . X X .
TIMERS SSP ADC UART
====================== === ======= ====
can safely be used by other peripherals, but may need to be
reconfigured when you wakeup from deep-sleep.
[2] INTERFACE can be configured to use either USBCDC or UART
+ [3] 3.2 only used when with the I2C bus (for IRQ)
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