commit 3e9464f2a9ca85fcc5cd56eb87611d6d94630c16
author Brian Silverman <brians> Fri Nov 01 15:36:08 2013 -0700
committer Brian Silverman <brians> Fri Nov 01 15:36:08 2013 -0700
tree fca2386c90ec305600a5f6c83c74efb35193ccf2
parent d6d30fd99a742dffa23498c1b1deb759a29ad7aa

disabled reading analog inputs with burst mode (for now at least)

gyro_board/src/usb/analog.c

diff --git a/gyro_board/src/usb/analog.c b/gyro_board/src/usb/analog.c
index b2ab48f..8dcaf26 100644
--- a/gyro_board/src/usb/analog.c
+++ b/gyro_board/src/usb/analog.c
@@ -2,19 +2,32 @@
 
 #include "LPC17xx.h"
 
+#define USE_BURST 0
+
 void analog_init(void) {
   SC->PCONP |= PCONP_PCAD;
 
-  // Enable AD0.0, AD0.1, AD0.2, AD0.3
+  // Enable AD0.0, AD0.1, AD0.2, and AD0.3.
   PINCON->PINSEL1 &= ~(3 << 14 | 3 << 16 | 3 << 18 | 3 << 20);
   PINCON->PINSEL1 |= 1 << 14 | 1 << 16 | 1 << 18 | 1 << 20;
+
+#if USE_BURST
   ADC->ADCR = (1 << 0 | 1 << 1 | 1 << 2 | 1 << 3) /* enable all 4 */ |
       7 << 8 /* 100MHz / 8 = 12.5MHz */ |
       1 << 16 /* enable burst mode */ |
       1 << 21 /* turn on ADC */;
+#else
+  ADC->ADCR = 7 << 8 /* 100MHz / 8 = 12.5MHz */ |
+      1 << 21 /* turn on ADC */;
+#endif
 }
 
 uint16_t analog(int channel) {
+#if !USE_BURST
+  // Set the channel number to the one we want.
+  ADC->ADCR = (ADC->ADCR & ~0xFF) | (1 << channel);
+  ADC->ADCR |= 1 << 24;  // start conversion
+#endif
   uint32_t value;
   do {
     switch (channel) {