Fix operator precedence bug in datagram ACK timeout calculation - #309
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In `MemoryConfigurationService`, `1 << (flags & 0x0F) * 1000` evaluated the
multiplication before the bitwise shift due to Java operator precedence.
This caused the exponent $N$ to shift by $(N \times 1000) \pmod{32}$, yielding
incorrect timeout intervals (e.g., 256 ms instead of 2 s for $N=1$, and 65.5 s
instead of 4 s for $N=2$).
Parenthesize the shift operation to compute $(1 \ll N) \times 1000\text{ ms}$
per the OpenLCB Datagram Transport Standard, and add corresponding unit tests.
bobjacobsen
approved these changes
Sep 25, 2026
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In$N$ to shift by $(N \times 1000) \pmod{32}$ , yielding incorrect timeout intervals (e.g., 256 ms instead of 2 s for $N=1$ , and 65.5 s instead of 4 s for $N=2$ ).
MemoryConfigurationService,1 << (flags & 0x0F) * 1000evaluated the multiplication before the bitwise shift due to Java operator precedence. This caused the exponentParenthesize the shift operation to compute$(1 \ll N) \times 1000\text{ ms}$ per the OpenLCB Datagram Transport Standard, and add corresponding unit tests.