unit_SCD4x_detail.hpp File Reference

Internal helpers shared by SCD40/SCD41 (and future SCD43) More...

#include <cstdint>

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Namespaces
namespace	m5
	Top level namespace of M5Stack.
namespace	detail
	Internal helpers shared across the SCD4x family (SCD40/SCD41/SCD43)

Functions
constexpr bool	m5::unit::scd4x::detail::is_sensor_variant (const uint8_t variant_high_byte, const uint8_t nibble)
	Does the get_sensor_variant high byte indicate the given variant?

Variables
constexpr uint8_t	m5::unit::scd4x::detail::VARIANT_NIBBLE_MASK {0xF0}
	Mask for the variant nibble (word[0] bits[15..12]) of get_sensor_variant (0x202F)
constexpr uint8_t	m5::unit::scd4x::detail::VARIANT_NIBBLE_SCD40 {0x00}
	SCD40 variant nibble (bits[15..12] == 0b0000)
constexpr uint8_t	m5::unit::scd4x::detail::VARIANT_NIBBLE_SCD41 {0x10}
	SCD41 variant nibble (bits[15..12] == 0b0001)
constexpr uint8_t	m5::unit::scd4x::detail::VARIANT_NIBBLE_SCD43 {0x50}
	SCD43 variant nibble (bits[15..12] == 0b0101)

Detailed Description

Internal helpers shared by SCD40/SCD41 (and future SCD43)

Not part of the public API. Included by the SCD4x unit implementations.

Function Documentation

is_sensor_variant()

bool m5::unit::scd4x::detail::is_sensor_variant ( const uint8_t variant_high_byte, const uint8_t nibble )

constexpr

Does the get_sensor_variant high byte indicate the given variant?

Parameters

variant_high_byte	High byte (word[0] bits[15..8]) read from get_sensor_variant (0x202F)
nibble	Expected variant nibble (e.g. VARIANT_NIBBLE_SCD41)

Only bits[15..12] identify the variant; bits[11..0] may differ per unit (datasheet CD_DS_SCD4x §3.10.6, issue #38), so compare the high nibble only.