ADC

Data Structures
struct	ADC_meas
	Container for ADC measurement results. More...

Functions
void	ADC_init (void)
	Initialize the external memory–mapped ADC interface.
void	ADC_start_conv (void)
	Start a conversion on the external ADC and wait for completion.
uint8_t	ADC_read_ch (void)
	Read the current ADC channel sample.
void	ADC_read_all (struct ADC_meas *output)
	Perform a full four-channel ADC conversion and return all results.
void	ADC_test (void)
	Internal ADC test routine. (Currently disabled in implementation.).

Detailed Description

Function Documentation

ADC_init()

void ADC_init

(

void

)

#include <adc.h>

Initialize the external memory–mapped ADC interface.

This prepares communication with the external ADC connected on the XMEM bus. All low-level XMEM configuration must already be handled elsewhere (e.g., via xmem_init()).

Definition at line 12 of file adc.c.

                    {
 
  // XMEM controls the ADC and is enabled elsewhere (xmem_init())
  // Do NOT touch DDR/PORTA (PORTA is the external data bus and is handeled
  // trough writing to and reading to xmem) No need to set up PD6/PD7; XMEM
  // controls WR/RD automatically when we read or write to memory allocted to
  // the ADC
}

Referenced by io_joystick_init().

ADC_read_all()

void ADC_read_all

(

struct ADC_meas *

output

)

#include <adc.h>

Perform a full four-channel ADC conversion and return all results.

Starts a conversion, then reads each channel sequentially with a small delay to satisfy ADC timing requirements.

Parameters

[out]

output

Pointer to a structure that will receive channel data.

Definition at line 36 of file adc.c.

                                           {
 
  ADC_start_conv();
 
  volatile uint8_t adc_value[4];
 
  // Send a pulse then read for each channel
  for (uint8_t i = 0; i < 4; i++) {
    _delay_ms(5);
    adc_value[i] = ADC_read_ch();
    output->channel[i] = adc_value[i];
  }
}

Referenced by io_joystick_read_position(), utils_joystick_print_pos(), and utils_joystick_print_raw().

ADC_read_ch()

uint8_t ADC_read_ch

(

void

)

#include <adc.h>

Read the current ADC channel sample.

Reads a single byte from the ADC's memory-mapped interface.

Returns

The 8-bit ADC result of the currently selected channel.

Definition at line 30 of file adc.c.

                          {
 
  // Read from any adress in ADC allocated memory adressarea to
  return *ADC_BASE_ADR;
}

Referenced by ADC_read_all().

ADC_start_conv()

void ADC_start_conv

(

void

)

#include <adc.h>

Start a conversion on the external ADC and wait for completion.

Triggers a write strobe through the ADC's memory interface and waits for the BUSY flag (PD4) to clear.

Definition at line 21 of file adc.c.

                          {
 
  // Write to any adress on ADC to trigger WR
  *ADC_BASE_ADR = 0x00;
  // Delay to ensure ADC conversion is done, checking BUSY pin insead.
  while ((PORTD & PD4)) {
  }
}

Referenced by ADC_read_all().

ADC_test()

void ADC_test

(

void

)

#include <adc.h>

Internal ADC test routine. (Currently disabled in implementation.).

Prints ADC values for channels 0–3 via UART.