USB-PD power

stusb4500: sink profiles, renegotiation and the current contract. More...

Classes
struct	stusb4500::Profile
	One sink profile (PDO): a voltage the board accepts and the current it draws. More...

Functions
bool	stusb4500::begin ()
	Sets up I2C1 and the control pins.
bool	stusb4500::setProfiles (const Profile *profiles, uint8_t count)
	Loads 1-3 profiles and renegotiates if they differ from the current ones.
uint8_t	stusb4500::getProfiles (Profile *out)
	Reads the active profiles.
uint8_t	stusb4500::boardProfiles (uint16_t max_millivolts, Profile *out)
	The board's profiles for Tools > USB-PD Power.
bool	stusb4500::renegotiate ()
	Asks the charger to negotiate again with the current profiles.
uint8_t	stusb4500::contractPosition ()
	Which charger offer is in use.
uint16_t	stusb4500::contractMilliamps ()
	Operating current agreed in the current contract.
uint32_t	stusb4500::vbusMillivolts ()
	VBUS measured by the on-board ADC (MAX11635 channel 3).

Variables
constexpr uint8_t	stusb4500::kMaxProfiles = 3
	Number of profiles the chip holds.

Detailed Description

stusb4500: sink profiles, renegotiation and the current contract.

Needs #include <stusb4500.h>. See stusb4500.h for how the profiles work and the UsbPdPower.ino example.

Function Documentation

begin()

bool stusb4500::begin

(

)

Sets up I2C1 and the control pins.

Returns

true if the chip answers.

Examples

UsbPdPower.ino.

boardProfiles()

uint8_t stusb4500::boardProfiles	(	uint16_t	max_millivolts,
		Profile *	out )

The board's profiles for Tools > USB-PD Power.

5 V/2 A, then 9 V/1 A if max_millivolts >= 9000, then max_millivolts at 10 W (schematic limit) if it is above 9 V.

Parameters

max_millivolts	Highest voltage to ask for, or 0 for "use the chip's stored settings".
out	Array with room for kMaxProfiles.

Returns

Number of profiles written to out; 0 for max_millivolts 0.

Examples

UsbPdPower.ino.

contractMilliamps()

uint16_t stusb4500::contractMilliamps

(

)

Operating current agreed in the current contract.

Returns

Current in mA; 0 = no contract.

Examples

UsbPdPower.ino.

contractPosition()

uint8_t stusb4500::contractPosition

(

)

Which charger offer is in use.

Returns

Position 1-7 of the offer; 0 = no PD contract (plain 5 V USB, or no charger attached).

Examples

UsbPdPower.ino.

getProfiles()

uint8_t stusb4500::getProfiles

(

Profile *

out

)

Reads the active profiles.

Parameters

out	Array with room for kMaxProfiles.

Returns

Number of profiles written to out.

Examples

UsbPdPower.ino.

renegotiate()

bool stusb4500::renegotiate

(

)

Asks the charger to negotiate again with the current profiles.

Returns

false if begin() has not run or the chip does not answer.

setProfiles()

bool stusb4500::setProfiles	(	const Profile *	profiles,
		uint8_t	count )

Loads 1-3 profiles and renegotiates if they differ from the current ones.

Parameters

profiles	Profiles in priority order, lowest first; the first must be 5 V.
count	Number of profiles, 1 to kMaxProfiles.

Returns

false if the arguments are invalid or the chip does not answer.

Examples

UsbPdPower.ino.

vbusMillivolts()

uint32_t stusb4500::vbusMillivolts

(

)

VBUS measured by the on-board ADC (MAX11635 channel 3).

Returns

Voltage in mV.

Examples

UsbPdPower.ino.