Datasheet for the Atmel ATxmega A1 series, the 100-pin members of the AVR XMEGA family. This 2.97 MB PDF focuses on device-specific data: pinout and alternate functions, memory sizes per part, package drawings, electrical characteristics and errata. Register-level operation of peripherals is described separately in the XMEGA A family manual. In repair work it helps locate power, PDI programming and reset pins, and check operating voltage limits, since XMEGA parts run at 3.6 V maximum rather than 5 V.
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