diff --git a/commands.cpp b/commands.cpp
deleted file mode 100644
index a171ee6..0000000
--- a/commands.cpp
+++ /dev/null
@@ -1,139 +0,0 @@
-
-#include <Arduino.h>
-#include "util.hpp"
-#include "commands.hpp"
-#include "serial.hpp"
-#include "tones.hpp"
-#include "scheduler.hpp"
-#include "eeprom.hpp"
-
-static void help() {
-	Serial.println("OK help");
-	Serial.println(" s: set    :s,index,freq,amplitude,");
-	Serial.println(" c: clear  :c,index,");
-	Serial.println(" g: get    :g,index,");
-	Serial.println(" w: write  :w,[v|s|c,...]...;,");
-	Serial.println("   o: option v,amplitude,us_per_tick,");
-	Serial.println("   s: set    s,timestamp,index,freq,");
-	Serial.println("   c: clear  v,timestamp,index,");
-	Serial.println(" p: play   :p,");
-	Serial.println(" q: stop   :q,");
-	Serial.println(" r: reset  :r,");
-	Serial.println(" e: eeprom :e,");
-	Serial.println(" h: help   :h,");
-}
-
-static bool get() {
-	int index = serial::read_int();
-	if(index < 0 || index >= size(tones::all)) {
-		return true;
-	}
-	if(index >= tones::active) {
-		tones::active = index + 1;
-	}
-	Serial.print("OK ");
-	Serial.print(index);
-	Serial.print(',');
-	Serial.print(tones::all[index].frequency);
-	Serial.print(',');
-	Serial.print(tones::all[index].amplitude);
-	Serial.print(',');
-	Serial.println();
-	return false;
-}
-
-static bool write() {
-	
-	scheduler::clear();
-
-	for(;;) {
-		serial::read_until();
-		switch(serial::buffer[0]) {
-			case 'o': {
-				float amplitude = serial::read_float();
-				uint32_t us_per_tick = serial::read_long();
-				scheduler::add_config(amplitude, us_per_tick);
-				break;
-			}
-			case 's': {
-				uint32_t ts = serial::read_long();
-				uint8_t index = serial::read_int();
-				uint16_t freq = serial::read_int();
-				scheduler::add_set(ts, index, freq);
-				break;
-			}
-			case 'c': {
-				uint32_t ts = serial::read_long();
-				uint8_t index = serial::read_int();
-				scheduler::add_clear(ts, index);
-				break;
-			}
-			case ';':
-				return false;
-			default:
-				return true;
-		}
-		Serial.println();
-	}
-
-	scheduler::finalize();
-}
-
-static const char HEXC[] = "0123456789abcdef";
-
-void commands::process() {
-	serial::read_until();
-	switch(serial::buffer[0]) {
-	case 'w':
-		if(write()) break;
-		Serial.println("OK");
-		return;
-	case 's': {
-		uint8_t index = serial::read_int();
-		uint16_t freq = serial::read_int();
-		float amp = serial::read_float();
-		tones::set(index, freq, amp);
-		Serial.println("OK");
-		return;
-	}
-	case 'c':
-		tones::clear(serial::read_int());
-		Serial.println("OK");
-		return;
-	case 'g':
-		if(get()) break;
-		return;
-	case 'p':
-		scheduler::running = false;
-		scheduler::do_next();
-		Serial.println("OK");
-		return;
-	case 'q':
-		scheduler::running = false;
-		Serial.println("OK");
-		return;
-	case 'e':
-		eeprom::jump(0);
-		Serial.println("OK serial");
-		for(int i = 0; i < 1024; i+=16) {
-			Serial.print(i);
-			Serial.print('\t');
-			eeprom::read(serial::buffer, 16);
-			for(int j = 0; j < 16; j++) {
-				Serial.print(HEXC[(serial::buffer[j] >> 4) & 0x0f]);
-				Serial.print(HEXC[serial::buffer[j] & 0x0f]);
-			}
-			Serial.println();
-		}
-	case 'r':
-		tones::clear_all();
-		Serial.println("OK");
-		return;
-	case 'h':
-		help();
-		return;
-	}
-
-	Serial.println("ERROR");
-}
-
diff --git a/commands.hpp b/commands.hpp
deleted file mode 100644
index 8c367c1..0000000
--- a/commands.hpp
+++ /dev/null
@@ -1,9 +0,0 @@
-
-#pragma once
-
-namespace commands {
-
-	void process();
-
-};
-
diff --git a/dac.hpp b/dac.hpp
index 88042c5..bd28d1b 100644
--- a/dac.hpp
+++ b/dac.hpp
@@ -5,18 +5,12 @@
 
 namespace dac {
 
-	constexpr int BITMASK_B = 0x07;
-	constexpr int BITMASK_D = 0xf8;
-
 	inline void init() {
-		DDRB |= BITMASK_B;
-		DDRD |= BITMASK_D;
+		DDRD = 0xff;
 	}
 	
 	inline void set(float v_f) {
-		uint8_t v = clamp((int)(v_f * -128) + 127, 0, 255);
-		PORTB = (PORTB & ~BITMASK_B) | (v & BITMASK_B);
-		PORTD = (PORTD & ~BITMASK_D) | (v & BITMASK_D);
+		PORTD = clamp((int)(v_f * -128) + 127, 0, 255);
 	}
 };
 
diff --git a/output.csv b/output.csv
deleted file mode 100644
index f37db72..0000000
--- a/output.csv
+++ /dev/null
@@ -1,249 +0,0 @@
-mode	ticks	timestamp	index	frequency	amplitude
-RUN config : 0.33, 488
-RUN set_ts	4882	2382964	0	1318	0.33
-RUN set		2382964	1	330	0.33
-RUN set_ts	4457	2175564	2	659	0.33
-RUN clear_ts	19106	9324276	1	0	0.00
-RUN clear_ts	55408	27039652	0	0	0.00
-RUN set_ts	55896	27277796	0	988	0.33
-RUN set		27277796	1	330	0.33
-RUN clear_ts	5008	2444452	2	0	0.00
-RUN clear_ts	25197	12296684	0	0	0.00
-RUN set_ts	40334	19683540	0	1046	0.33
-RUN set		19683540	2	659	0.33
-RUN clear_ts	54982	26831764	1	0	0.00
-RUN clear_ts	12077	5894124	0	0	0.00
-RUN set_ts	27213	13280492	0	1174	0.33
-RUN set		13280492	1	330	0.33
-RUN clear_ts	41862	20429204	2	0	0.00
-RUN set_ts	16369	7988620	2	659	0.33
-RUN clear_ts	31265	15257868	1	0	0.00
-RUN clear_ts	5622	2744084	0	0	0.00
-RUN set_ts	6123	2988572	0	1046	0.33
-RUN set		2988572	1	330	0.33
-RUN clear_ts	21147	10320284	2	0	0.00
-RUN clear_ts	47888	23369892	0	0	0.00
-RUN set_ts	63546	31010996	0	988	0.33
-RUN set		31010996	2	659	0.33
-RUN clear_ts	13164	6424580	1	0	0.00
-RUN clear_ts	42827	20900124	0	0	0.00
-RUN set_ts	60660	29602628	0	880	0.33
-RUN set		29602628	1	220	0.33
-RUN clear_ts	8371	4085596	2	0	0.00
-RUN set_ts	2978	1453812	2	440	0.33
-RUN clear_ts	17627	8602524	1	0	0.00
-RUN clear_ts	53929	26317900	0	0	0.00
-RUN set_ts	54417	26556044	0	880	0.33
-RUN set		26556044	1	220	0.33
-RUN clear_ts	3529	1722700	2	0	0.00
-RUN clear_ts	23718	11574932	0	0	0.00
-RUN set_ts	38855	18961788	0	1046	0.33
-RUN set		18961788	2	440	0.33
-RUN clear_ts	53503	26110012	1	0	0.00
-RUN clear_ts	10598	5172372	0	0	0.00
-RUN set_ts	25734	12558740	0	1318	0.33
-RUN set		12558740	1	220	0.33
-RUN clear_ts	40383	19707452	2	0	0.00
-RUN set_ts	12614	6156180	2	440	0.33
-RUN clear_ts	27262	13304404	1	0	0.00
-RUN clear_ts	62100	30305348	0	0	0.00
-RUN set_ts	62588	30543492	0	1174	0.33
-RUN set		30543492	1	220	0.33
-RUN clear_ts	11700	5710148	2	0	0.00
-RUN clear_ts	31889	15562380	0	0	0.00
-RUN set_ts	47026	22949236	0	1046	0.33
-RUN set		22949236	2	440	0.33
-RUN clear_ts	61674	30097460	1	0	0.00
-RUN clear_ts	17304	8444900	0	0	0.00
-RUN set_ts	34394	16784820	0	988	0.33
-RUN set		16784820	1	208	0.33
-RUN clear_ts	47089	22979980	2	0	0.00
-RUN set_ts	36898	18006772	2	415	0.33
-RUN clear_ts	51547	25155484	1	0	0.00
-RUN clear_ts	22313	10889292	0	0	0.00
-RUN set_ts	22801	11127436	0	988	0.33
-RUN set		11127436	1	208	0.33
-RUN clear_ts	37449	18275660	2	0	0.00
-RUN clear_ts	57638	28127892	0	0	0.00
-RUN set_ts	7239	3533180	0	1046	0.33
-RUN set		3533180	2	415	0.33
-RUN clear_ts	21887	10681404	1	0	0.00
-RUN clear_ts	44518	21725332	0	0	0.00
-RUN set_ts	59654	29111700	0	1174	0.33
-RUN set		29111700	1	208	0.33
-RUN clear_ts	8767	4278844	2	0	0.00
-RUN set_ts	46534	22709140	2	415	0.33
-RUN clear_ts	61182	29857364	1	0	0.00
-RUN clear_ts	30484	14876740	0	0	0.00
-RUN set_ts	30972	15114884	0	1318	0.33
-RUN set		15114884	1	208	0.33
-RUN clear_ts	45620	22263108	2	0	0.00
-RUN set_ts	15410	7520628	2	415	0.33
-RUN clear_ts	30058	14668852	1	0	0.00
-RUN clear_ts	336	164516	0	0	0.00
-RUN set_ts	2778	1356212	0	1046	0.33
-RUN set		1356212	1	220	0.33
-RUN clear_ts	15473	7551372	2	0	0.00
-RUN set_ts	5282	2578164	2	440	0.33
-RUN clear_ts	19931	9726876	1	0	0.00
-RUN clear_ts	56233	27442252	0	0	0.00
-RUN set_ts	56721	27680396	0	880	0.33
-RUN set		27680396	1	220	0.33
-RUN clear_ts	5833	2847052	2	0	0.00
-RUN set_ts	41159	20086140	2	440	0.33
-RUN clear_ts	55807	27234364	1	0	0.00
-RUN clear_ts	27550	13444948	0	0	0.00
-RUN set_ts	28038	13683092	0	880	0.33
-RUN set		13683092	1	220	0.33
-RUN clear_ts	42687	20831804	2	0	0.00
-RUN set_ts	14918	7280532	2	440	0.33
-RUN clear_ts	29566	14428756	1	0	0.00
-RUN clear_ts	64404	31429700	0	0	0.00
-RUN set_ts	64892	31667844	0	247	0.33
-RUN set		31667844	1	494	0.33
-RUN clear_ts	14004	6834500	2	0	0.00
-RUN clear_ts	18568	9061732	1	0	0.00
-RUN set_ts	49330	24073588	1	262	0.33
-RUN set		24073588	2	523	0.33
-RUN clear_ts	63978	31221812	0	0	0.00
-RUN clear_ts	3983	1944252	2	0	0.00
-RUN set_ts	36698	17909172	0	294	0.33
-RUN clear_ts	49393	24104332	1	0	0.00
-RUN set_ts	39202	19131124	1	587	0.33
-RUN clear_ts	53851	26279836	0	0	0.00
-RUN set_ts	25105	12251788	0	1174	0.33
-RUN set		12251788	2	294	0.33
-RUN clear_ts	39753	19400012	1	0	0.00
-RUN set_ts	9543	4657532	1	587	0.33
-RUN clear_ts	24191	11805756	2	0	0.00
-RUN clear_ts	61470	29997908	0	0	0.00
-RUN set_ts	61958	30236052	0	1397	0.33
-RUN set		30236052	2	294	0.33
-RUN clear_ts	11071	5403196	1	0	0.00
-RUN clear_ts	33701	16446636	0	0	0.00
-RUN set_ts	48838	23833492	0	1760	0.33
-RUN set		23833492	1	587	0.33
-RUN clear_ts	63486	30981716	2	0	0.00
-RUN set_ts	33276	16239236	2	294	0.33
-RUN clear_ts	47924	23387460	1	0	0.00
-RUN clear_ts	2577	1258124	0	0	0.00
-RUN set_ts	17714	8644980	0	587	0.33
-RUN clear_ts	32362	15793204	2	0	0.00
-RUN set_ts	5082	2480564	1	1568	0.33
-RUN set		2480564	2	294	0.33
-RUN clear_ts	17777	8675724	0	0	0.00
-RUN clear_ts	57985	28297228	1	0	0.00
-RUN set_ts	7586	3702516	0	1397	0.33
-RUN set		3702516	1	587	0.33
-RUN clear_ts	22235	10851228	2	0	0.00
-RUN clear_ts	43888	21417892	0	0	0.00
-RUN set_ts	59025	28804748	0	1318	0.33
-RUN set		28804748	2	262	0.33
-RUN clear_ts	8137	3971404	1	0	0.00
-RUN set_ts	43463	21210492	1	523	0.33
-RUN clear_ts	58111	28358716	2	0	0.00
-RUN set_ts	30342	14807444	2	262	0.33
-RUN clear_ts	44991	21956156	1	0	0.00
-RUN set_ts	17222	8404884	1	523	0.33
-RUN clear_ts	31870	15553108	2	0	0.00
-RUN clear_ts	1172	572484	0	0	0.00
-RUN set_ts	1660	810628	0	1046	0.33
-RUN set		810628	2	262	0.33
-RUN clear_ts	16308	7958852	1	0	0.00
-RUN clear_ts	36497	17811084	0	0	0.00
-RUN set_ts	51634	25197940	0	1318	0.33
-RUN set		25197940	1	523	0.33
-RUN clear_ts	746	364596	2	0	0.00
-RUN set_ts	39002	19033524	2	262	0.33
-RUN clear_ts	51697	25228684	1	0	0.00
-RUN set_ts	41506	20255476	1	523	0.33
-RUN clear_ts	56155	27404188	2	0	0.00
-RUN clear_ts	26921	13137996	0	0	0.00
-RUN set_ts	27409	13376140	0	1174	0.33
-RUN set		13376140	2	262	0.33
-RUN clear_ts	42057	20524364	1	0	0.00
-RUN clear_ts	617	301644	0	0	0.00
-RUN set_ts	11847	5781884	0	1046	0.33
-RUN set		5781884	1	523	0.33
-RUN clear_ts	26495	12930108	2	0	0.00
-RUN clear_ts	49126	23974036	0	0	0.00
-RUN set_ts	64262	31360404	0	988	0.33
-RUN set		31360404	2	208	0.33
-RUN clear_ts	13375	6527548	1	0	0.00
-RUN set_ts	51142	24957844	1	415	0.33
-RUN clear_ts	254	124500	2	0	0.00
-RUN set_ts	35580	17363588	2	208	0.33
-RUN clear_ts	50228	24511812	1	0	0.00
-RUN clear_ts	17577	8578124	0	0	0.00
-RUN set_ts	20018	9769332	0	1046	0.33
-RUN set		9769332	1	415	0.33
-RUN clear_ts	34666	16917556	2	0	0.00
-RUN clear_ts	55832	27246564	0	0	0.00
-RUN set_ts	7386	3604916	0	1174	0.33
-RUN set		3604916	2	208	0.33
-RUN clear_ts	20081	9800076	1	0	0.00
-RUN set_ts	9890	4826868	1	415	0.33
-RUN clear_ts	24539	11975580	2	0	0.00
-RUN clear_ts	46192	22542244	0	0	0.00
-RUN set_ts	61329	29929100	0	1318	0.33
-RUN set		29929100	2	208	0.33
-RUN clear_ts	10441	5095756	1	0	0.00
-RUN set_ts	45767	22334844	1	415	0.33
-RUN clear_ts	60415	29483068	2	0	0.00
-RUN clear_ts	32158	15693652	0	0	0.00
-RUN set_ts	32646	15931796	0	1046	0.33
-RUN set		15931796	2	220	0.33
-RUN clear_ts	47295	23080508	1	0	0.00
-RUN set_ts	19526	9529236	1	440	0.33
-RUN clear_ts	34174	16677460	2	0	0.00
-RUN clear_ts	3476	1696836	0	0	0.00
-RUN set_ts	3964	1934980	0	880	0.33
-RUN set		1934980	2	220	0.33
-RUN clear_ts	18612	9083204	1	0	0.00
-RUN set_ts	53938	26322292	1	440	0.33
-RUN clear_ts	3050	1488948	2	0	0.00
-RUN clear_ts	38864	18966180	0	0	0.00
-RUN set_ts	41306	20157876	0	880	0.33
-RUN set		20157876	2	220	0.33
-RUN clear_ts	54001	26353036	1	0	0.00
-RUN set_ts	43810	21379828	1	440	0.33
-RUN clear_ts	58459	28528540	2	0	0.00
-RUN clear_ts	29225	14262348	0	0	0.00
-RUN set_ts	29713	14500492	0	220	0.33
-RUN clear_ts	44361	21648716	1	0	0.00
-RUN set_ts	14151	6906236	1	440	0.33
-RUN clear_ts	28799	14054460	0	0	0.00
-RUN clear_ts	15679	7651900	1	0	0.00
-RUN set_ts	9690	4729268	0	1318	0.33
-RUN set		4729268	1	220	0.33
-RUN set_ts	12194	5951220	2	440	0.33
-RUN clear_ts	26843	13099932	1	0	0.00
-RUN set_ts	63633	31053452	1	220	0.33
-RUN clear_ts	12745	6220108	2	0	0.00
-RUN set_ts	48071	23459196	2	440	0.33
-RUN clear_ts	62719	30607420	1	0	0.00
-RUN clear_ts	34462	16818004	0	0	0.00
-RUN set_ts	34950	17056148	0	1046	0.33
-RUN set		17056148	1	220	0.33
-RUN clear_ts	49599	24204860	2	0	0.00
-RUN set_ts	21830	10653588	2	440	0.33
-RUN clear_ts	36478	17801812	1	0	0.00
-RUN set_ts	6268	3059332	1	220	0.33
-RUN clear_ts	20916	10207556	2	0	0.00
-RUN set_ts	56242	27446644	2	440	0.33
-RUN clear_ts	5354	2613300	1	0	0.00
-RUN clear_ts	41168	20090532	0	0	0.00
-RUN set_ts	43610	21282228	0	1174	0.33
-RUN set		21282228	1	208	0.33
-RUN clear_ts	56305	27477388	2	0	0.00
-RUN set_ts	46114	22504180	2	415	0.33
-RUN clear_ts	60763	29652892	1	0	0.00
-RUN set_ts	32017	15624844	1	208	0.33
-RUN clear_ts	46665	22773068	2	0	0.00
-RUN set_ts	16455	8030588	2	415	0.33
-RUN clear_ts	31103	15178812	1	0	0.00
-RUN clear_ts	2846	1389396	0	0	0.00
-RUN set_ts	3334	1627540	0	988	0.33
-RUN set		1627540	1	0	0.33
-RUN stop
-
diff --git a/scheduler.cpp b/scheduler.cpp
index 261af6f..3e95eec 100644
--- a/scheduler.cpp
+++ b/scheduler.cpp
@@ -17,23 +17,31 @@ struct {
 	uint8_t index;
 	uint16_t frequency;
 	float amplitude;
+	bool active = false;
 } next;
 
 constexpr uint64_t bm(int n) {
 	return ((uint64_t)1 << n) - 1;
 }
 
+void scheduler::init() {
+	eeprom::jump(0);
+	tones::clear_all();
+	ts_init = micros();
+	running = true;
+}
+
 void scheduler::do_next() {
 	
 	int i = 1;
 
 	if(running) {
-		tones::set(next.index, next.frequency, next.amplitude);
+		if(next.active) {
+			tones::set(next.index, next.frequency, next.amplitude);
+			next.active = false;
+		}
 	} else {
-		eeprom::jump(0);
-		tones::clear_all();
-		ts_init = micros();
-		running = true;
+		init();
 	}
 
 	uint64_t v = 0;
@@ -44,78 +52,69 @@ void scheduler::do_next() {
 	int entry_size = entry::get_size(type);
 	eeprom::read(buff + 1, entry_size - 1);
 
-
-	Serial.print("LOAD (");
-
 	for(int i = 0; i < entry_size; i++) {
 		v = (v << 8) | buff[i];
-		Serial.print(buff[i]);
-		Serial.print(", ");
 	}
 
-
-	Serial.print(") ");
-
 	switch(type) {
 		case entry::Type::config: {
 			config.amplitude = *(float*)(buff + 4);
 			v >>= 32;
 			config.us_per_tick = v & bm(29);
 			ts_init = micros();
-
-			Serial.print("config\t");
-			Serial.print(config.amplitude);
-			Serial.print('\t');
-			Serial.println(config.us_per_tick);
 			break;
 		}
 		case entry::Type::set: {
-			Serial.println("set");
 			v >>= 4;
 			next.frequency = v & bm(12);
 			v >>= 12;
 			next.index = v & bm(5);
 			next.amplitude = config.amplitude;
+			next.active = true;
 			break;
 		}
 		case entry::Type::set_ts: {
-			Serial.println("set_ts");
 			next.frequency = v & bm(12);
 			v >>= 12;
 			uint32_t ticks = v & bm(20);
 			v >>= 20;
 			next.index = v & bm(5);
 			next.amplitude = config.amplitude;
+			next.active = true;
 			timestamp = ticks * config.us_per_tick + ts_init;
 			break;
 		}
 		case entry::Type::clear: {
-			Serial.println("clear");
 			next.index = v & bm(5);
 			next.frequency = 0;
 			next.amplitude = 0;
+			next.active = true;
 			break;
 		}
 		case entry::Type::clear_ts: {
-			Serial.println("clear_ts");
 			v >>= 4;
 			uint32_t ticks = v & bm(20);
 			v >>= 20;
 			next.index = v & bm(5);
 			next.frequency = 0;
 			next.amplitude = 0;
+			next.active = true;
 			timestamp = ticks * config.us_per_tick + ts_init;
 			break;
 		}
 		default: {
 			running = false;
 			tones::clear_all();
-			Serial.println("stop");
 			break;
 		}
 	}
+}
 
-	Serial.println("DONE");
+void scheduler::do_all() {
+	while(running && timing::at >= timestamp) {
+		do_next();
+	}
+	tones::recalc();
 }
 
 void scheduler::clear() {
@@ -123,41 +122,3 @@ void scheduler::clear() {
 	ts_last = 0;
 }
 
-void scheduler::add_set(uint32_t ts, uint8_t index, uint16_t freq) {
-//	if(index >= size(tones::all)) {
-//		return;
-//	}
-//	if(ts <= ts_last) {
-//		entry::Set e {.type=entry::Type::SET, .index=index, .frequency=freq};
-//		eeprom::write(&e, sizeof(e));
-//	} else {
-//		entry::SetTS e {.type=entry::Type::SET_TS, .index=index, .ticks=ts, .frequency=freq};
-//		eeprom::write(&e, sizeof(e));
-//		ts_last = ts;
-//	}
-}
-
-void scheduler::add_clear(uint32_t ts, uint8_t index) {
-//	if(index >= size(tones::all)) {
-//		return;
-//	}
-//	if(ts <= ts_last) {
-//		entry::Clear e {.type=entry::Type::CLEAR, .index=index};
-//		eeprom::write(&e, sizeof(e));
-//	} else {
-//		entry::ClearTS e {.type=entry::Type::CLEAR_TS, .index=index, .ticks=ts};
-//		eeprom::write(&e, sizeof(e));
-//		ts_last = ts;
-//	}
-}
-
-void scheduler::add_config(float amplitude, uint32_t us_per_tick) {
-//	entry::Config e {.type=entry::Type::CONFIG, .p=0, .us_per_tick=us_per_tick, .amplitude=amplitude};
-//	eeprom::write(&e, sizeof(e));
-}
-
-void scheduler::finalize() {
-//	entry::Header e {.type=entry::Type::STOP};
-//	eeprom::write(&e, sizeof(e));
-}
-
diff --git a/scheduler.hpp b/scheduler.hpp
index 778641c..d44f009 100644
--- a/scheduler.hpp
+++ b/scheduler.hpp
@@ -6,11 +6,9 @@ namespace scheduler {
 	inline uint32_t timestamp = 0;
 	inline bool running = false;
 	
+	void init();
 	void do_next();
+	void do_all();
 	void clear();
-	void add_set(uint32_t ts, uint8_t index, uint16_t freq);
-	void add_clear(uint32_t ts, uint8_t index);
-	void add_config(float volume, uint32_t us_per_tick);
-	void finalize();
 };
 
diff --git a/serial.cpp b/serial.cpp
deleted file mode 100644
index f297a04..0000000
--- a/serial.cpp
+++ /dev/null
@@ -1,30 +0,0 @@
-
-#include "util.hpp"
-#include "serial.hpp"
-#include <Arduino.h>
-
-void serial::init() {
-	Serial.begin(115200);
-	Serial.println("READY");
-}
-
-void serial::read_until(char ch) {
-	buffer[Serial.readBytesUntil(ch, buffer, sizeof(buffer) - 1)] = '\0';
-}
-
-float serial::read_float(char ch) {
-	read_until(ch);
-	return atof(buffer);
-}
-
-long serial::read_long(char ch) {
-	read_until(ch);
-	return atol(buffer);
-}
-
-int serial::read_int(char ch) {
-	read_until(ch);
-	return atoi(buffer);
-}
-
-
diff --git a/serial.hpp b/serial.hpp
deleted file mode 100644
index 2d29871..0000000
--- a/serial.hpp
+++ /dev/null
@@ -1,14 +0,0 @@
-
-#pragma once
-
-namespace serial {
-
-	inline char buffer[16];
-
-	void init();
-	void read_until(char ch = ',');
-	float read_float(char ch = ',');
-	int read_int(char ch = ',');
-	long read_long(char ch = ',');
-};
-
diff --git a/size.hpp b/size.hpp
deleted file mode 100644
index 7b87be3..0000000
--- a/size.hpp
+++ /dev/null
@@ -1,5 +0,0 @@
-
-#pragma once
-
-#define size(V) (sizeof(V) / sizeof(V[0]))
-
diff --git a/tone-generator.ino b/tone-generator.ino
index 8256cec..cd80a47 100644
--- a/tone-generator.ino
+++ b/tone-generator.ino
@@ -1,7 +1,5 @@
 
-#include "commands.hpp"
 #include "tone.hpp"
-#include "serial.hpp"
 #include "tones.hpp"
 #include "dac.hpp"
 #include "timing.hpp"
@@ -19,30 +17,22 @@ inline unsigned long micros_diff() {
 
 void setup() {
 	dac::init();
-	serial::init();
-  scheduler::do_next();
+  tones::init();
+  scheduler::init();
 }
 
 void loop() {
-  if(scheduler::running) {
-    if(timing::at >= scheduler::timestamp) {
-      scheduler::do_next();
-    }
-  }
-  else if(Serial.available() && Serial.read() == ':') {
-    commands::process();
+  if(scheduler::running && timing::at >= scheduler::timestamp) {
+    scheduler::do_all();
   }
 
   timing::update();
   
   float value = 0;
-  uint32_t passed = ((uint64_t)timing::diff << (20)) / 1000000L;
+  uint32_t passed = timing::diff;
 
   for(int i = 0; i < tones::active; i++) {
     Tone& t = tones::all[i];
-    if(!t.active()) {
-      continue;
-    }
     t.update(passed);
     value += t.get();
   }
diff --git a/tones.cpp b/tones.cpp
index 31169cd..e25b1f9 100644
--- a/tones.cpp
+++ b/tones.cpp
@@ -3,6 +3,39 @@
 #include "tones.hpp"
 #include "tone.hpp"
 
+using tones::all;
+using tones::active;
+
+static uint8_t lookup[size(all)];
+static uint8_t rlookup[size(all)];
+
+void tones::init() {
+	for(uint8_t i = 0; i < size(all); i++) {
+		lookup[i] = i;
+		rlookup[i] = i;
+	}
+}
+
+void tones::recalc() {
+	int j = 0;
+	for(int i = 0; i < size(all); i++) {
+		if(all[j].active()) {
+			j++;
+			continue;
+		}
+		if(!all[i].active()) {
+			continue;
+		}
+		if(i != j) {
+			swap(all[i], all[j]);
+			swap(rlookup[i], rlookup[j]);
+			swap(lookup[rlookup[i]], lookup[rlookup[j]]);
+		}
+		j++;
+	}
+	active = j;
+}
+
 void tones::clear_all() {
 	for(int i = 0; i < size(all); i++) {
 		all[i] = {0, 0, 0};
@@ -10,36 +43,16 @@ void tones::clear_all() {
 	active = 0;
 }
 
-void tones::clear(uint8_t index) {
-	if(index >= size(all)) {
-		return;
-	}
-	all[index] = {0, 0, 0};
-
-	if(index == active - 1) {
-		prune(index);
-	}
-}
-
 void tones::set(uint8_t index, uint16_t frequency, float amplitude) {
-	if(amplitude == 0) {
-		return clear(index);
-	}
 	if(index >= size(all)) {
 		return;
 	}
-	all[index].frequency = frequency;
-	all[index].amplitude = amplitude;
-
-	if(index >= tones::active) {
-		tones::active = index + 1;
+	Tone& t = all[lookup[index]];
+	if(amplitude == 0) {
+		t = {0, 0, 0};
+	} else {
+		t.frequency = frequency;
+		t.amplitude = amplitude;
 	}
 }
 
-void tones::prune(uint8_t index) {
-	int i;
-	for(i = index; i >= 0 && all[i].amplitude == 0; i--) {
-	}
-	active = i + 1;
-}
-
diff --git a/tones.hpp b/tones.hpp
index 49b8fa6..0d2c0dd 100644
--- a/tones.hpp
+++ b/tones.hpp
@@ -8,9 +8,9 @@ namespace tones {
 	inline Tone all[32];
 	inline int active;
 
-	void prune(uint8_t index);
+	void init();
 	void set(uint8_t index, uint16_t frequency, float amplitude);
-	void clear(uint8_t index);
 	void clear_all();
+	void recalc();
 }
 
diff --git a/util.hpp b/util.hpp
index 1977be9..0dda16e 100644
--- a/util.hpp
+++ b/util.hpp
@@ -6,5 +6,12 @@ inline T clamp(T v, T a, T b) {
 	return min(max(v, a), b);
 }
 
+template <typename T>
+inline void swap(T& a, T& b) {
+	T t = b;
+	b = a;
+	a = t;
+}
+
 #define size(V) (sizeof(V) / sizeof(V[0]))