view ringtools/imy/durations.c @ 999:30fad2b3afd2

doc/Flash-write-protection: document flash lock-state retrieval
author Mychaela Falconia <falcon@freecalypso.org>
date Mon, 04 Dec 2023 20:40:50 +0000
parents fd4c9bc7835d
children
line wrap: on
line source

/*
 * This module implements the step of precomputing various note durations
 * in TDMA frames.
 */

extern unsigned beats_per_min;
unsigned tdma_durations[6][4];

static float modifier_values[4] = {1.0f, 1.5f, 1.75f, 2.0f / 3.0f};

compute_note_durations()
{
	float beat_ref, basic_ms[6], dur_ms;
	unsigned dur_tdma;
	int i, j;

	beat_ref = 60000.0f / beats_per_min;
	basic_ms[0] = beat_ref * 4.0f;
	basic_ms[1] = beat_ref * 2.0f;
	basic_ms[2] = beat_ref;
	basic_ms[3] = beat_ref / 2.0f;
	basic_ms[4] = beat_ref / 4.0f;
	basic_ms[5] = beat_ref / 8.0f;
	for (i = 0; i < 6; i++) {
		for (j = 0; j < 4; j++) {
			dur_ms = basic_ms[i] * modifier_values[j];
			dur_tdma = dur_ms * 13.0f / 60.0f + 0.5f;
			tdma_durations[i][j] = dur_tdma;
		}
	}
}