From: Keith Packard <keithp@keithp.com>
Date: Mon, 17 Jun 2013 21:52:32 +0000 (-0700)
Subject: altos/lpc: Get rid of ADC filter
X-Git-Tag: 1.2.9.4~157
X-Git-Url: https://git.gag.com/?p=fw%2Faltos;a=commitdiff_plain;h=025beb0fea011d0e3dab59b5d16e7ffae97c613c

altos/lpc: Get rid of ADC filter

Now that the source of the Vcc noise has been identified, remove the
unnecessary ADC filtering.

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

diff --git a/src/lpc/ao_adc_lpc.c b/src/lpc/ao_adc_lpc.c
index 40173aa4..874d2d29 100644
--- a/src/lpc/ao_adc_lpc.c
+++ b/src/lpc/ao_adc_lpc.c
@@ -95,22 +95,12 @@
 
 static uint8_t		ao_adc_ready;
 
-static uint16_t		ao_adc_prev[AO_NUM_ADC];
-
-#define sample(id)	do {				\
-		uint16_t	p = *prev;		\
-		uint16_t	v = lpc_adc.dr[id];	\
-		p -= p >> 4;				\
-		p += v >> 4;				\
-		*prev++ = p;				\
-		*out++ = p >> 1;			\
-	} while (0)
+#define sample(id)	(*out++ = lpc_adc.dr[id] >> 1)
 
 void  lpc_adc_isr(void)
 {
 	uint32_t	stat = lpc_adc.stat;
 	uint16_t	*out;
-	uint16_t	*prev;
 
 	/* Turn off burst mode */
 	lpc_adc.cr = 0;
@@ -119,7 +109,6 @@ void  lpc_adc_isr(void)
 	/* Store converted values in packet */
 
 	out = (uint16_t *) &ao_data_ring[ao_data_head].adc;
-	prev = ao_adc_prev;
 #if AO_ADC_0
 	sample(0);
 #endif