Add beep/led support.

Support our P2_0 connected buzzer, and formalize LED output support.

Signed-off-by: Keith Packard <keithp@keithp.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/ao_adc.c b/ao_adc.c
index d45e10b1..f043b5a1 100644
--- a/ao_adc.c
+++ b/ao_adc.c
@@ -18,8 +18,8 @@
 
 #include "ao.h"
 
-__xdata struct ao_adc	ao_adc_ring[ADC_RING];
-__data uint8_t		ao_adc_head;
+volatile __xdata struct ao_adc	ao_adc_ring[ADC_RING];
+volatile __data uint8_t		ao_adc_head;
 
 void ao_adc_isr(void) interrupt 1
 {