X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=src%2Fmicropeak%2Fao_async.c;h=3556f54c00d511932baabad43a3d358311233d0f;hb=23dc9a63ae8bc982d9352cfb7a3f508d8a08c374;hp=04bba9e81fa7669e5f3347b58077d7a6f68e64fc;hpb=fc2e5beb9173663e1e37a9b5a7b6eea1046222f7;p=fw%2Faltos

diff --git a/src/micropeak/ao_async.c b/src/micropeak/ao_async.c
index 04bba9e8..3556f54c 100644
--- a/src/micropeak/ao_async.c
+++ b/src/micropeak/ao_async.c
@@ -21,20 +21,51 @@
 #define AO_ASYNC_BAUD	38400l
 #define AO_ASYNC_DELAY	(uint8_t) (1000000l / AO_ASYNC_BAUD)
 
+#define LED_PORT	PORTB
+
+void
+ao_async_start(void)
+{
+	LED_PORT |= (1 << AO_LED_SERIAL);
+}
+
+void
+ao_async_stop(void)
+{
+	LED_PORT &= ~(1 << AO_LED_SERIAL);
+}
+
 void
 ao_async_byte(uint8_t byte)
 {
 	uint8_t		b;
 	uint16_t	w;
 
-	/* start bit */
-
-	/* start     data         stop */
-	w = 0x001 | (byte << 1) | 0x000;
+	/*    start           data           stop */
+	w = (0x000 << 0) | (byte << 1) | (0x001 << 9);
 
+	ao_arch_block_interrupts();
 	for (b = 0; b < 10; b++) {
-		ao_led_set((w & 1) << AO_LED_SERIAL);
+		uint8_t	v = LED_PORT & ~(1 << AO_LED_SERIAL);
+		v |= (w & 1) << AO_LED_SERIAL;
+		LED_PORT = v;
 		w >>= 1;
-		ao_delay_us(26);
+
+		/* Carefully timed to hit around 9600 baud */
+		asm volatile ("nop");
+		asm volatile ("nop");
+
+		asm volatile ("nop");
+		asm volatile ("nop");
+		asm volatile ("nop");
+		asm volatile ("nop");
+		asm volatile ("nop");
+
+		asm volatile ("nop");
+		asm volatile ("nop");
+		asm volatile ("nop");
+		asm volatile ("nop");
+		asm volatile ("nop");
 	}
+	ao_arch_release_interrupts();
 }