Diff: adcdma.c

Revision:

0:08a4d61cd84c

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/adcdma.c	Tue Sep 20 12:46:26 2011 +0000
@@ -0,0 +1,152 @@
+/*************************************************************
+
+ History
+ 2011/07/26 - Add "shape_mode" option. 
+
+
+*************************************************************/
+#include "MODDMA.h"
+
+#define SAMPLE_BUFFER_LENGTH 256
+
+extern int shape_mode;
+
+// for ADC DMA read
+static MODDMA dma;
+static MODDMA_Config *conf = new MODDMA_Config;
+static uint32_t adcInputBuffer[SAMPLE_BUFFER_LENGTH];   
+
+/******************
+To read ADC DMA
+*******************/
+// Configuration callback on TC
+void TC0_callback(void) {
+    
+  MODDMA_Config *config = dma.getConfig();
+
+  // Disbale burst mode and switch off the IRQ flag.
+  LPC_ADC->ADCR &= ~(1UL << 16);
+  LPC_ADC->ADINTEN = 0;    
+    
+  // Finish the DMA cycle by shutting down the channel.
+  dma.haltAndWaitChannelComplete( (MODDMA::CHANNELS)config->channelNum());
+  dma.Disable( (MODDMA::CHANNELS)config->channelNum() );
+
+  // Clear DMA IRQ flags.
+  if (dma.irqType() == MODDMA::TcIrq) dma.clearTcIrq();    
+  if (dma.irqType() == MODDMA::ErrIrq) dma.clearErrIrq();
+
+  int m=0,max=0,n=0;
+  int downtrend=0;
+  int errata=0;
+
+  for (int i = 0; i < SAMPLE_BUFFER_LENGTH; i++) {
+      int channel = (adcInputBuffer[i] >> 24) & 0x7;
+      int iVal = (adcInputBuffer[i] >> 4) & 0xFFF;
+//      double fVal = 3.3 * (double)((double)iVal) / ((double)0x1000); // scale to 0v to 3.3v
+//      pc.printf("Array index %02d : ADC input channel %d = 0x%03x %01.3f volts\n", i, channel, iVal, fVal);
+
+    if( channel == 0 ){
+
+        n = iVal;
+
+//PEAKMAX
+        if(!downtrend){
+            max= n>max ? n:max;
+            if(n<max){
+                downtrend=1;
+            }
+        }else{
+            if (n>max+100)
+                errata=1;
+        }
+
+//Accumulation
+        m+=n;
+
+        if (shape_mode) {       //  2011/07/26
+            double fVal = 3.3 * (double)((double)n) / ((double)0x1000);
+            printf("%01.3f\n",fVal);
+        }
+     }    
+
+      if(n==0 && max !=0) break;
+  }
+
+    if(!errata){
+        if (shape_mode) {       //  2011/07/26
+            double fm = 3.3 * (double)((double)m) / ((double)0x1000);
+            double fmax = 3.3 * (double)((double)max) / ((double)0x1000);
+            printf("%01.3f,%01.3f\n",fm,fmax);
+        }
+        printf("%d,%d\n",m,max);
+
+        if (shape_mode) {       //  2011/07/26
+            printf("-----\n");
+        }
+    }
+}
+
+// Configuration callback on Error
+void ERR0_callback(void) {
+    // Switch off burst conversions.
+    LPC_ADC->ADCR |= ~(1UL << 16);
+    LPC_ADC->ADINTEN = 0;
+    error("Oh no! My Mbed EXPLODED! :( Only kidding, go find the problem");
+}
+
+void read_dma_data()
+{
+    memset(adcInputBuffer, 0, sizeof(adcInputBuffer));
+    
+    // Prepare configuration.
+    dma.Setup( conf );
+    
+    // Enable configuration.
+    dma.Enable( conf );
+    
+    // Enable ADC irq flag (to DMA).
+    // Note, don't set the individual flags,
+    // just set the global flag.
+    LPC_ADC->ADINTEN = 0x100;
+
+    // Enable burst mode on inputs 0 and 1.
+    LPC_ADC->ADCR |= (1UL << 16); 
+    return;
+}
+
+void setup_adcdma()
+{
+  // We use the ADC irq to trigger DMA and the manual says
+  // that in this case the NVIC for ADC must be disabled.
+  NVIC_DisableIRQ(ADC_IRQn);
+    
+  // Power up the ADC and set PCLK
+  LPC_SC->PCONP    |=  (1UL << 12);
+  LPC_SC->PCLKSEL0 &= ~(3UL << 24); // PCLK = CCLK/4 96M/4 = 24MHz
+   
+  // Enable the ADC, 12MHz
+  LPC_ADC->ADCR  = (1UL << 21) | (1UL << 8) | (1UL << 0);
+  
+  // Set the pin functions to ADC
+  LPC_PINCON->PINSEL1 &= ~(3UL << 14);  /* P0.23, Mbed p15. */
+  LPC_PINCON->PINSEL1 |=  (1UL << 14);
+
+// Prepare an ADC configuration.
+//  MODDMA_Config *conf = new MODDMA_Config;
+
+  conf
+   ->channelNum    ( MODDMA::Channel_0 )
+   ->srcMemAddr    ( 0 )
+   ->dstMemAddr    ( (uint32_t)adcInputBuffer )
+   ->transferSize  ( SAMPLE_BUFFER_LENGTH )
+   ->transferType  ( MODDMA::p2m )
+   ->transferWidth ( MODDMA::word )
+   ->srcConn       ( MODDMA::ADC )
+   ->dstConn       ( 0 )
+   ->dmaLLI        ( 0 )
+   ->attach_tc     ( &TC0_callback )
+   ->attach_err    ( &ERR0_callback )
+  ; // end conf.
+}
+