diff --git a/irr_main.c b/irr_main.c
index 92c77ff..ec5d287 100644
--- a/irr_main.c
+++ b/irr_main.c
@@ -164,11 +164,12 @@ struct chaninfo {
 	GPIO_TypeDef *bank;
 	uint16_t pinnum;
 	bool init;
+	bool invert;
 } chans[] = {
-	[0] = { .bank = GPIOB, .pinnum = GPIO_PIN_5, .init = true, },
-	[1] = { .bank = GPIOB, .pinnum = GPIO_PIN_6, .init = true, },
-	[2] = { .bank = GPIOB, .pinnum = GPIO_PIN_7, .init = true, },
-	[3] = { .bank = GPIOB, .pinnum = GPIO_PIN_9, .init = true, },
+	[0] = { .bank = GPIOB, .pinnum = GPIO_PIN_5, .init = true, .invert = true, },
+	[1] = { .bank = GPIOB, .pinnum = GPIO_PIN_6, .init = true, .invert = true, },
+	[2] = { .bank = GPIOB, .pinnum = GPIO_PIN_7, .init = true, .invert = true, },
+	[3] = { .bank = GPIOB, .pinnum = GPIO_PIN_9, .init = true, .invert = true, },
 	[4] = { .bank = GPIOB, .pinnum = GPIO_PIN_8, .init = true, },
 };
 #define nitems(x)	(sizeof(x) / sizeof *(x))
@@ -180,7 +181,8 @@ set_chan(uint32_t chan, bool val)
 
 	if (chan < nitems(chans)) {
 		ci = chans[chan];
-		HAL_GPIO_WritePin(ci.bank, ci.pinnum, val ? GPIO_PIN_SET : GPIO_PIN_RESET);
+		HAL_GPIO_WritePin(ci.bank, ci.pinnum, val ^ ci.invert ?
+		    GPIO_PIN_SET : GPIO_PIN_RESET);
 	}
 }
 
@@ -202,7 +204,70 @@ setup_gpio()
 	}
 }
 
-void
+static struct sched {
+	uint32_t cmd;
+	uint32_t end_wait_tick;	/* end if running, otherwise how long to wait */
+	uint32_t chan;
+} schedule[20];
+static int schedpos;		/* position in schedule, % nitems(schedule)*/
+static int schedcnt;		/* total items waiting */
+
+#define SCHED_HEAD	(schedule[(schedpos) % nitems(schedule)])
+#define SCHED_TAIL	(schedule[(schedpos + schedcnt) % nitems(schedule)])
+
+static void
+start_sched(struct sched *sched)
+{
+
+	sched->end_wait_tick += uwTick;
+
+	if (sched->cmd == CMD_RUNFOR)
+		set_chan(sched->chan, 1);
+}
+
+static void
+process_sched()
+{
+
+	/* nothing to do? */
+	if (schedcnt == 0)
+		return;
+
+	/* not yet expired */
+	if (uwTick < SCHED_HEAD.end_wait_tick)
+		return;
+
+	if (SCHED_HEAD.cmd == CMD_RUNFOR)
+		set_chan(SCHED_HEAD.chan, 0);
+
+	/* we are done, advance */
+	schedpos++;
+	schedcnt--;
+
+	if (schedcnt)
+		start_sched(&SCHED_HEAD);
+}
+
+static void
+enqueue_sched(uint32_t cmd, uint32_t ticks, uint32_t chan)
+{
+
+	if (schedcnt >= nitems(schedule))
+		return;
+
+	SCHED_TAIL = (struct sched){
+		.cmd = cmd,
+		.end_wait_tick = ticks,
+		.chan = chan,
+	};
+
+	if (schedcnt == 0)
+		start_sched(&SCHED_HEAD);
+
+	schedcnt++;
+}
+
+static void
 procmsg(struct pktbuf inbuf, struct pktbuf *outbuf)
 {
 	uint32_t args[5];
@@ -220,6 +285,19 @@ procmsg(struct pktbuf inbuf, struct pktbuf *outbuf)
 	outbuf->pkt[0] = inbuf.pkt[0];
 
 	switch (inbuf.pkt[0]) {
+	case CMD_WAITFOR:
+		if (apos == 1)
+			enqueue_sched(CMD_WAITFOR, args[0], -1);
+		break;
+
+	case CMD_RUNFOR:
+		if (apos == 2)
+			enqueue_sched(CMD_RUNFOR, args[0], args[1]);
+		break;
+
+	case CMD_PING:
+		break;
+
 	case CMD_SETUNSET:
 		if (apos == 2)
 			set_chan(args[0], args[1]);
@@ -298,6 +376,8 @@ main()
 	//Radio.Rx(0);
 
 loop:
+	process_sched();
+
 	BoardLowPowerHandler();
 	if (Radio.IrqProcess != NULL)
 		Radio.IrqProcess();