dali: more improvements

2 files changed, 45 insertions, 25 deletions

diff --git a/can.c b/can.c
index c2307a9..b8cb21f 100644
--- a/can.c
+++ b/can.c
@@ -221,16 +221,10 @@ int main(void)
 	can_init();
 	can_CANSTAT();
 
-	cli();
-	dali_word = 0xff08;	/* ON */
-	dali_state = 1;
-	sei();
-	_delay_ms(25);
-
-	cli();
-	dali_word = 0xff08;	/* OFF */
-	dali_state = 1;
-	sei();
+	dali_send(0xff08);
+	while (dali_queue_busy())
+		;
+	dali_send(0xff08);
 
 	for (int i = 0; i < 40; i++)
 		_delay_ms(25);
@@ -243,21 +237,14 @@ int main(void)
 		}
 		_delay_ms(40);
 		ctr++;
-		if (ctr == 40) {
-			dali_word = 0xff91;
-			dali_state = 1;
-		}
-		if (ctr == 80) {
-			dali_word = 0xff99;
-			dali_state = 1;
-		}
-		if (ctr == 120) {
-			dali_word = 0xffa0;
-			dali_state = 1;
-		}
+		if (ctr == 40)
+			dali_send(0xff91);
+		if (ctr == 80)
+			dali_send(0xff99);
+		if (ctr == 120)
+			dali_send(0xffa0);
 		if (ctr == 160) {
-			dali_word = 0xff90;
-			dali_state = 1;
+			dali_send(0xff90);
 			ctr = 0;
 		}
 	}
diff --git a/dali.c b/dali.c
index 5b9d25d..83007a3 100644
--- a/dali.c
+++ b/dali.c
@@ -1,9 +1,17 @@
+/* invalid command, used as default/do-nothing value
+ * 101CCCCX == special commands, X must be 1.
+ * X is 0 below => invalid
+ */
+#define DALI_INVALID	0xa000
+
 static uint16_t dali_word, dali_sendq;
 static uint8_t dali_subctr, dali_state, dali_bit;
 static uint8_t dali_prevpin;
 
 enum dali_state {
 	DALI_IDLE = 0,
+	DALI_TX_SPACE,
+
 	DALI_TX_STARTBIT1,
 	DALI_TX_STARTBIT2,
 
@@ -22,7 +30,7 @@ ISR(TIMER0_COMPA_vect)
 	TCNT0 = 0;	/* CTC mode didn't work, CBA to debug */
 
 	data = (PIND >> D_DALII) & 1;
-	if (dali_state == DALI_IDLE && data) {
+	if (dali_state <= DALI_TX_SPACE && data) {
 		dali_state = DALI_RX_LEFT;
 		dali_subctr = 4;
 		dali_word = 1;
@@ -48,6 +56,18 @@ ISR(TIMER0_COMPA_vect)
 	switch (dali_state) {
 	/* idle */
 	case DALI_IDLE:
+		if (dali_sendq != DALI_INVALID) {
+			dali_word = dali_sendq;
+			dali_sendq = DALI_INVALID;
+			dali_state = DALI_TX_STARTBIT1;
+		}
+		return;
+
+	case DALI_TX_SPACE:
+		/* 12 ms inter-command spacing */
+		if (dali_bit > 28)
+			dali_state = DALI_IDLE;
+		dali_bit++;
 		return;
 
 	/* write */
@@ -109,6 +129,19 @@ ISR(TIMER0_COMPA_vect)
 	}
 }
 
+static void dali_send(uint16_t word)
+{
+	cli();
+	dali_sendq = word;
+	sei();
+}
+
+static bool dali_queue_busy(void)
+{
+	asm volatile ("" : : : "memory");
+	return dali_sendq != DALI_INVALID;
+}
+
 static void dali_init(void)
 {
 	PORTD |= (1 << D_DALII);