Class VREF

• Defined in File sim_vref.h

Nested Relationships

Nested Types

• Struct VREF::ref_t

Inheritance Relationships

Base Type

• public Peripheral (Class Peripheral)

Derived Types

• public ArchAVR_VREF (Class ArchAVR_VREF)

• public ArchXT_VREF (Class ArchXT_VREF)

Class Documentation

class VREF : public Peripheral

Generic model for managing VREF for analog peripherals (ADC, analog comparator)

Note

Setting VCC in the firmware is required for using any analog feature of a MCU. Failing to do so will trigger a device crash.

Subclassed by ArchAVR_VREF, ArchXT_VREF

Public Types

enum Source

Enumation value for the sources of voltage references.

Values:

enumerator Source_VCC

VCC voltage value.

enumerator Source_AVCC

AVCC voltage value (always equal to VCC for now)

enumerator Source_AREF

AREF voltage value.

enumerator Source_Internal

Internal reference voltage value.

enum SignalId

Values:

enumerator Signal_ARefChange

Raised when the AREF reference value is changed. data carries the new value (absolute)

enumerator Signal_IntRefChange

Raised when an internal reference value is changed. data carries the new value (relative to VCC) and index the reference index.

enumerator Signal_VCCChange

Raised when VCC value is changed. data carries the new value (absolute)

Public Functions

explicit VREF(unsigned int ref_count)

inline bool active() const

virtual bool ctlreq(ctlreq_id_t req, ctlreq_data_t *data) override

Virtual method called for a CTL request. The method must return true if the request has been processed.

Protected Functions

void set_reference(unsigned int index, Source source, double voltage = 1.0)

Set a voltage reference value

If source is VCC or AVCC, the voltage value is ignored (it is by definition 1.0).

If source is AREF, voltage must be a value relative to VCC/AVCC.

If source is Internal, voltage must be an absolute value in Volts.

Parameters:

• index – channel index of the reference

• source – source of the reference

• voltage – Value of the reference (optional, default value is 1.0)

double reference(unsigned int index) const

Returns a voltage reference value.

The value returned is always relative to VCC, even if set with an absolute value.

The value is also constrained to the range [0; VCC].

If index is out of range or VCC is not set, 0.0 is returned.