jandelgado / jled / 33175647107

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fix(avr): compute the effect end time in 32 bits (#193)

In Update(), "period + delay_after_" and the following
"cycle_period * num_repetitions_" product were both evaluated in int.
On AVR int is 16 bits wide and uint16_t is unsigned int, so neither
operand promotes to anything wider and both expressions wrap at 65536.
Blink(500, 500).Repeat(100) computed an end time of 34463ms instead of
99999ms, stopping after roughly a third of its intended length.

JLed 4.0 cast the sum to uint32_t. The cast was lost in the 5.0 state
machine rewrite. Give cycle_period an explicit uint32_t type to restore
32 bit arithmetic for both expressions.

Platforms where int is 32 bits are unaffected: the signed and unsigned
products share the same low 32 bits and time_end is uint32_t, so the
computed value is identical there. The added regression test therefore
passes on the host with and without this fix, and only discriminates on
a 16 bit int target.

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