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-rw-r--r--src/c/hardware/avr/adc/u8AVRADCSetups.c42
-rw-r--r--src/c/hardware/avr/adc/u8AVRReadADCs.c46
2 files changed, 88 insertions, 0 deletions
diff --git a/src/c/hardware/avr/adc/u8AVRADCSetups.c b/src/c/hardware/avr/adc/u8AVRADCSetups.c
new file mode 100644
index 00000000..620f80fe
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+++ b/src/c/hardware/avr/adc/u8AVRADCSetups.c
@@ -0,0 +1,42 @@
+// Function to initialise ADC of AVR
+//
+// Calling Sequence
+// AVRSetupADC(uint8 prescalar, uint8 adc_ref)
+//
+// Parameters
+// prescalar: prescalar to be used for generating ADC clock (0-7)
+// adc_ref : reference voltage to be used for ADC conversion
+// 0 -> Voltage on VREF pin
+// 1 -> Voltage on AVCC pin
+// 2 -> Internal 2.56 reference voltage
+//
+// Description
+// This function initialises ADc of AVR with given parameters. 'prescalar' is
+// needed for deciding ADC clock. ADC clock should be between 50KHz and 200KHz
+// and it given as (MCU clock/2^prescalar). Select appropriate prescalar depending
+// on MCU clock. 'adc_ref' selects one of the available reference voltage sources
+// available
+// Examples
+// AVRADCSetup(128,0)
+//
+// Authors
+// Siddhesh Wani
+//
+
+#include "AVRPeripheralADC.h"
+
+
+uint8 u8AVRADCSetups(uint8 prescalar, uint8 adc_ref)
+{
+ /*Set the prescalar value*/
+ ADCSRA |= (prescalar & 0x07);
+
+ /*Set the adc reference voltage*/
+ ADMUX |= ((adc_ref & 0x03) << 6);
+
+ /*Enable ADC hardware. Set ADEN bit*/
+ ADCSRA |= (1<<7);
+
+ return 0;
+}
+
diff --git a/src/c/hardware/avr/adc/u8AVRReadADCs.c b/src/c/hardware/avr/adc/u8AVRReadADCs.c
new file mode 100644
index 00000000..71fe1363
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+++ b/src/c/hardware/avr/adc/u8AVRReadADCs.c
@@ -0,0 +1,46 @@
+// Function to get voltage on analog pin on AVR
+//
+// Calling Sequence
+// u8AVRReadADCs(channel)
+//
+// Parameters
+// channel : Select which channel is to be read. Values from 0-7 select one
+// of the pins ADC0-ADC7. For other possible channel values refer
+// datasheet
+// Returns->
+// result : Digital value for the voltage present on channel selected
+//
+// Description
+// This function returns digital value for present on adc pins. 'channel'
+// selects which of the ADC0-ADC7 is to be used for reading analog value.
+// Apart from reading just ADC0-ADC7 other it can also read differential
+// voltages between some pins. For channel values for those options, please
+// refer datasheet.
+//
+// Examples
+// adc_result = u8AVRReadADC(0) //Read ADC0
+//
+// Authors
+// Siddhesh Wani
+//
+
+
+#include "AVRPeripheralADC.h"
+
+uint16 u8AVRReadADCs(uint8 channel)
+{
+ /*Set ADC conversion channel*/
+ ADMUX |= (channel & 0x1F);
+
+ /*Start ADC conversion. Set 'ADSC' bit*/
+ ADCSRA |= (1<<6);
+
+ /*Wait for conversion to complete. Check 'ADIF' bit*/
+ while(!(ADCSRA & (1<<4)));
+
+ /*Clear ADIF flag*/
+ ADCSRA |= (1<<4);
+
+ /*ADC conversion result is stored in ADCH/L registers*/
+ return (ADC);
+}