Initial public release of WII5 Buoy firmware

Firmware for an autonomous wave-measurement buoy (ATmega2560-based
WII5 v2 board). Reads wave motion from a Sparton AHRS-M1/M2 IMU,
samples GPS and battery state, and reports back over Iridium SBD
satellite telemetry. Originally developed 2012-2024.

This is the first public release. Code, documentation, and field-tested
operating modes (Capture, Sleep, Position, ManualTest, SelfTest,
LowBattery) are licensed under Apache 2.0 — see LICENSE and NOTICE.

See README.md for an overview and build instructions, CONTRIBUTING.md
for how to contribute, and DEPLOYMENTS.md for the field-deployment log.

tools/2024/ui.txt

@@ -0,0 +1,7 @@
+# Reference snippet (not directly executable): the avrdude command for
+# burning the stk500v2 mega2560 bootloader. Use parameterized scripts in this
+# directory instead.
+#
+# avrdude -C <avrdude.conf> -v -patmega2560 -cstk500v2 -Pusb \
+#     -Uflash:w:<path to stk500boot_v2_mega2560.hex>:i \
+#     -Ulock:w:0x0F:m