ESP8266 painless mesh, sometimes does not connect - arduino-esp8266

Question

I have a simple setup between 2 wemos d1 boards. They work with a painless mesh.
The devices each have buttons and LEDs with which users can interact with one another.
The problem that I am having, is that sometimes the two units don't connect after one of them is turned off. I am extensively testing what happens when one of the 2 nodes falls off and then comes back on again. Sometimes they connect fast, sometimes slow, and sometimes they won't connect at all.
Retrying to reset the turned-off module mostly works but sometimes I need to reset the first module as well or they will never connect again. Judging by the LEDs and operation the program keeps running. Resetting both devices always works to reconnect the two.
// #define wrong_led // I may or may not have made a slight error in soldering the duo leds
bool connected = 0 ;
const uint32_t R1 = 1000 ;
const uint32_t R2 = 4700 ;
const uint32_t threshold[] =
{
/*4 * 1023 * R1 / ( R2 + ( 4 * R1) ) , // 470 ->*/ 682,
/*3 * 1023 * R1 / ( R2 + ( 3 * R1) ) , // 398 ->*/ 579,
/*2 * 1023 * R1 / ( R2 + ( 2 * R1) ) , // 305 ->*/ 446,
/*1 * 1023 * R1 / ( R2 + ( 1 * R1) ) , // 179 ->*/ 262,
/*0 * 1023 * R1 / ( R2 + ( 0 * R1) ) , // 0 */ 0,
} ;
const int nSections = 5 ;
#ifdef wrong_led
const int red[] = { D0, D2, D4, D6, 3 } ;
const int green[] = { D1, D3, D5, D7, 1 } ;
#else
const int green[] = { D0, D2, D4, D6, 3 } ;
const int red[] = { D1, D3, D5, D7, 1 } ;
#endif
const int switchesPin = A0 ;
uint32_t timeOut[nSections] = {0,0,0,0} ;
const int debugPin = 2 ; // DEBUG TEST ME
const uint32_t timeOutInterval = 3000 ;
const uint32_t sendInterval = 2000 ;
const uint32_t connectionTimeout = 10000 ;
enum tokenStates
{
AVAILABLE,
IN_POSSESSION,
TAKEN,
} ;
uint8_t token[ nSections ] ;
Debounce button[] =
{
Debounce ( 255 ),
Debounce ( 255 ),
Debounce ( 255 ),
Debounce ( 255 ),
Debounce ( 255 )
} ;
/************** FUNCTIONS **************/
void updateLEDs()
{
if( !connected )
{
REPEAT_MS( 500 )
{
for (int i = 0; i < nSections ; i++) digitalWrite( red[i], !digitalRead(red[i] )) ; // toggle all red lights during connecting
}
END_REPEAT
}
else for (int i = 0; i < nSections ; i++)
{
switch (token[i])
{
case AVAILABLE: analogWrite( green[i], 32 ) ; // green
digitalWrite( red[i], LOW ) ; break;
case IN_POSSESSION:analogWrite( green[i], 32 ) ; // yellow
digitalWrite( red[i], HIGH ) ; break;
case TAKEN: digitalWrite( green[i], LOW ) ; // red
digitalWrite( red[i], HIGH ) ; break;
}
}
} ;
void newConnection(uint32_t nodeId)
{
connected = 1 ;
}
void debounceInputs()
{
REPEAT_MS( 50 )
{
int sample = analogRead( switchesPin ) ;
for (int i = 0; i < nSections ; i++)
{
uint16_t ref ;
if( threshold[i] >= 35 ) ref = threshold[i] ;
else ref = 35 ;
if( sample >= ref - 35
&& sample <= ref + 35 ) button[i].debounceInputs( 1 ) ;
else button[i].debounceInputs( 0 ) ;
}
} END_REPEAT
}
void processInputs( )
{
for (int i = 0; i < nSections ; i++ )
{
String message = "" ;
message += i ;
message += ',' ;
if( button[i].readInput() == FALLING )
{
if( token[i] == TAKEN ) { continue ; } // token is claimed by another discard button press
else if( token[i] == AVAILABLE ) // if the token is available.....
{
token[i] = IN_POSSESSION ; // claim the token
message += TAKEN ;
}
else if( token[i] == IN_POSSESSION ) // if the token is in possession
{
token[i] = AVAILABLE ; // free up the token
message += AVAILABLE ;
}
mesh.sendBroadcast( message ) ;
}
}
}
void transceiveTokens()
{
static uint8_t index = 0 ;
REPEAT_MS( sendInterval / nSections ) // if we claimed atleast 1 token, transmitt this once every second
{
if( token[index] == IN_POSSESSION )
{
String message = "" ;
message += index ;
message += ',' ;
message += TAKEN ;
mesh.sendBroadcast( message ) ;
}
if( ++ index == nSections ) index = 0 ;
}
END_REPEAT
for (int i = 0; i < nSections ; i++ )
{
if( token[i] != IN_POSSESSION // if a node which claimed a token is turned off while still possessing the token
&& millis() - timeOut[i] >= timeOutInterval ) // the token becomes available again after a timeout
{
token[i] = AVAILABLE ;
}
}
}
void incomingMessage( uint32 from, String msg )
{
uint32_t tokenState ;
uint32_t tokenID ;
char char_array[32];
strcpy(char_array, msg.c_str());
sscanf( char_array, "%d,%d", &tokenID, &tokenState ) ;
if( token[ tokenID ] == IN_POSSESSION && tokenState == TAKEN ) // if we have the token and an other also claims the token...
{ // .. free the token again, and transmitt it.
token[ tokenID ] = AVAILABLE ;
String message = "" ;
message += tokenID ;
message += ',' ;
message += AVAILABLE ;
mesh.sendBroadcast( message ) ;
}
if( tokenState == AVAILABLE )
{
token[ tokenID ] = AVAILABLE ;
}
token[tokenID] = tokenState ; // update token with state
if( token[tokenID] == TAKEN )
{
timeOut[tokenID] = millis() ; // set timeout
}
}
void setup()
{
debounceInputs() ; // to be sure
mesh.init( MESH_PREFIX, MESH_PASSWORD, MESH_PORT );
mesh.onReceive(&incomingMessage );
mesh.onNewConnection( &newConnection );
for( int i = 0 ; i < nSections ; i ++ )
{
pinMode( green[i], OUTPUT ) ;
pinMode( red[i], OUTPUT ) ;
digitalWrite( green[i], LOW ) ;
digitalWrite( red[i], LOW ) ;
}
}
void loop()
{
debounceInputs() ;
processInputs( ) ;
updateLEDs() ;
transceiveTokens() ;
mesh.update() ;
if( millis() > connectionTimeout ) // the first node which is powered on, does need to work eventually, even when it is the only one.
{
connected = 1 ;
}
}
I am yet to build three more units. I am hoping that having a network with at least 2 active nodes at all times will solve this problem.
I am curious as to why it sometimes does work and sometimes it does not work.
AFAIK I am not making any obvious mistakes. None of the functions in loop() take incredibly long, but I do not know how fast mesh.update() ; is to be called. For all I know, the functions together take too long. However, if both nodes are not turned off there seem to be no problems at all. Intervals between messages are also larger than 100ms. About mesh.update() the painless mesh website only states that:
This routine runs various maintainance tasks... Not super interesting, but things don't work without it.
What could it be?