Speaker Controller

Files
file	speaker_ctrl_handler.cpp
	implemntation file for speaker handler
file	speaker_ctrl_handler.hpp
	header file for speaker handler

Classes
class	SpeakerCtrlHandler

Macros
#define	SUBSCRIBE_TOPIC   "/speakerReq"
	topic that the speaker controller subscribe to
#define	PUBLISH_TOPIC   "/speakerRes"
	topic that the speaker controller will publish replies to
#define	SPKR_PWR_PIN   14
	pins for controlling the power source to the speaker, probably controlling through a relay instead of directly to the speaker
#define	SPKR_PWR_ON_STATE   1
	the state of the power control pin if the speaker is powered on
#define	SPKR_INC_PIN   5
	pins that interact witht the INC pin of the digital pot, negative edge on this pin will move the digital pot wiper
#define	SPKR_DIR_PIN   4
	pins that controls the DIR pin of the digital pot, used for controlling whether the negative edge on the INC pin result in increase or decrease in resistance
#define	SPKR_SELECT_PIN   12
	pin that controls the CS line of the digital pot, the digital pot will only changes its resistance if the CS pin is active
#define	VOLUME_UP_LIMIT   100
	Max possible volume set by the user.
#define	VOLUME_DOWN_LIMIT   0
	Min possible volume set by the user.
#define	SPKR_VOLUME_DELAY_MS   1
	delay between toggling the INC pin to make sure the edge is registered by the digital pot
#define	SPKR_INC_ACTIVATED_STATE   0
	the state that the INC pin is activated, the pin triggers on negative edge so its activated state is low
#define	SPKR_PIN_UP_STATE   1
	the state of the pin that controls the DIR pin of the digital pot when the pot is in moving up resistance mode
#define	SPKR_SELECT_ACTIVATED   0
	the state of the pin that controls the CS pin of the digital pot when the pot is activated
#define	SPKR_VOL_LEVEL_INPUT_PIN   0
	pins for sensing analog voltage of the physical pot
#define	SPKR_VOL_LEVEL_INPUT_THRESHOLD   15
	minimum change in adc voltage before it's considered that the user moved the pot
#define	SPKR_VOL_LEVEL_MAX_COUNT   1024
	max value returned by the adc read function of mongoose
#define	SPKR_PWR_INPUT_PIN   13
	pins for sensing user turning on/off the speaker using the physical pot
#define	SPKR_PWR_INPUT_OFF_STATE   1
	the state the the input pin will be at if it's off, since it's pulled up so the off state will be one
#define	REGISTER_INTERRUPT()
	dummy function, interrupts are registered in the handler constructor for this device More...
#define	TOTAL_HANDLER   1
	device only needs to handle speaker type interface
#define	SPKR_HANDLER_INDEX   0
	index of the pointer to the speaker handler
#define	INITIALIZE_HANDLER()
	initialize list of handler More...

Functions
void	handlePolling (struct mg_connection *mgCon, ParentHandler *handlerList[], char *jsonBuf)
	poll the voltage on the potentiometer and change the volume if there is a change in voltage More...
static void	SpeakerCtrlHandler::pwrInputIntHandler (int pin, void *arg)
	handler function for when the user turn on/off the physical pot on the speaker This function will either turn on/off the speaker based on the user interaction with the physical potentiometer More...
	SpeakerCtrlHandler::SpeakerCtrlHandler (void)
	Construct a new Speaker Ctrl Handler:: Speaker Ctrl Handler object create a new spekaer handler, intialize the namespace argument, prepare analog, and interrupt pins, set speaker to mute.
HandlerError	SpeakerCtrlHandler::handleRequest (struct mg_connection *mgCon, struct mg_str *message, char *commandName, char *response)
	function to handle request passed by aws mqtt Depending on the reques type, the handler will either mute the device, adjust volume or set new volume entirely More...
HandlerError	SpeakerCtrlHandler::handleReport (char *stateReport)
	handle preparing report for the speaker handler used when the handler needs to respond to the , will report whether the speaker is muted and what the volume is More...
void	SpeakerCtrlHandler::checkPotVoltage (void)
	called by the main polling function to check and update the pot voltage if necessary read the adc voltage and if the voltage changes over a certain threshold, which indicates that the user has moved the pot, then the volume will be adjusted accordingly

Detailed Description

Macro Definition Documentation

#define INITIALIZE_HANDLER

(

)

Value:

static SpeakerCtrlHandler spkrController; \
  static ParentHandler*     _handlerList[TOTAL_HANDLER] = {&spkrController};

initialize list of handler

#define REGISTER_INTERRUPT

(

)

Value:

do {                       \
  } while (0)

dummy function, interrupts are registered in the handler constructor for this device

Register an interrupt before handling any events, usually you would register interrupt inside the constructor of the handler but this is provided to register interrupt early in the program if needed

Function Documentation

void handlePolling	(	struct mg_connection *	mgCon,
		ParentHandler *	handlerList[],
		char *	jsonBuf
	)

poll the voltage on the potentiometer and change the volume if there is a change in voltage

dummy empty function since bed room light controller has no polling need

Parameters

mgCon	object representing connection to the internet
_handlerList	the list of handler that user defined
jsonBuf	if you write something to this buffer, it will be published to the mqtt server of the device

HandlerError SpeakerCtrlHandler::handleReport ( char *  stateReport )

virtual

handle preparing report for the speaker handler used when the handler needs to respond to the , will report whether the speaker is muted and what the volume is

Parameters

stateReport

the buffer to write the report to

Returns

HandlerError return problem error

Implements ParentHandler.

HandlerError SpeakerCtrlHandler::handleRequest ( struct mg_connection *  mgCon, struct mg_str *  message, char *  commandName, char *  response  )

virtual

function to handle request passed by aws mqtt Depending on the reques type, the handler will either mute the device, adjust volume or set new volume entirely

Parameters

mgCon	mongoose OS connection to the internet
message	message received by mongoose OS
commandName	the command extracted from the message
response	the buffer to write the response to, which will be published to the mqtt response server

Returns

HandlerError return errors reported by function inside the handler

Implements ParentHandler.

void SpeakerCtrlHandler::pwrInputIntHandler ( int  pin, void *  arg  )

static

handler function for when the user turn on/off the physical pot on the speaker This function will either turn on/off the speaker based on the user interaction with the physical potentiometer

Parameters

pin	the pin that triggered the handler
arg	pointer to things passed by mongoose OS to the handler, in this case, the pointer to the speaker handler is registered to be the argument passed