Lichtkrant met Bluetooth

Dit is een leuk project voor beginners en gevorderden. Lichtkranten blijven populair, de rode leds geven een 'old school' uitstraling.

Deze lichtkrant is uitgerust met bluetooth dus je kunt de tekst makkelijk veranderen met behulp van een Android telefoon of tablet.

Bekijk de video

Onderdelen

Wat heb je nodig?
Hier is een lijst met onderdelen.
De genoemde prijzen zijn van november 2017, die kunnen dus afwijken

	Led Displays Max7219 Dit is het display, je hebt er minimaal 1 nodig, 2 is nog mooier! In de video gebruik ik er twee. Deze koop je bij opencircuit.nl Kostprijs: €9,50
	Arduino Nano Dit is de Arduino Nano, je hebt er 1 nodig Deze koop je bij opencircuit.nl Kostprijs: €7,95 In plaats van de Arduino Nano, kun je ook de Arduino Uno gebruiken
	Bluetooth Slave Module Dit is de HC-06 Bluetooth Slave, je hebt er 1 nodig Deze koop je bij opencircuit.nl Kostprijs: €6,95
	Voeding 5volt Dit is de voeding, 5 volt, 1A. Deze koop je bij opencircuit.nl Kostprijs: €6,50
	Voeding 5volt Dit is een alternatieve voeding, 5 volt, 1A. Deze koop je bij opencircuit.nl Kostprijs: €5,00 Als je voor deze optie gaat, heb je ook deze nodig Kostprijs: €0,50 Hier te koop: opencircuit.nl

Schema

Hier is het schema, In de video vertel ik er meer over
Klik om te vergroten!

Arduino Libraries en Sketch

Je hebt twee externe libraries nodig. De MD_MAX72xx en de MD_Parola.
Om die te installeren is het handig om even te zoeken naar MD_Max, vervolgens vind je ze makkelijk

De juiste module selecteren (niet meer nodig sinds november 2018)

Na de installatie van de libraries, moeten we de MD_Max72xx library vertellen welke led matrix module wij gebruiken.
Ga op de harde schijf op zoek naar het bestand: MD_MAX72xx.h (op windows in de folder C:\Users\jouw naam\Documents\Arduino\libraries\MD_MAX72XX\src\)

In dat bestand, op regel 214, zie je staan:
   #define    USE_PAROLA_HW   1, verander die 1 in 0
Op regel 237 zie je staan:
   #define    USE_FC16_HW       0, verander die 0 in 1.

De Sketch

Hier is de arduino sketch voor de Arduino Uno of Arduino Nano
// 4 december 2018. Update i.v.m. Nieuwe libraries // MD_MAX72XX is version 3.0.2 // MD_Parola is version 3.0.1 #include <MD_Parola.h> #include <MD_MAX72xx.h> #include <SPI.h> #include <SoftwareSerial.h> #include <EEPROM.h> #define HARDWARE_TYPE MD_MAX72XX::FC16_HW #define MAX_DEVICES 8 #define CLK_PIN 13 #define DATA_PIN 11 #define CS_PIN 10 // Use softserial for the bluetooth module SoftwareSerial mySerial(2, 3); // HARDWARE SPI MD_Parola LK = MD_Parola(HARDWARE_TYPE, CS_PIN, MAX_DEVICES); uint8_t scrollSpeed = 30; // default frame delay value textEffect_t scrollEffect = PA_SCROLL_LEFT; textPosition_t scrollAlign = PA_LEFT; uint16_t scrollPause = 2000; // in milliseconds // Global message buffers shared by Serial and Scrolling functions #define BUF_SIZE 75 char curMessage[BUF_SIZE]; char newMessage[BUF_SIZE]; bool newMessageAvailable = false; void setup() { // Enable the next line to clear the message from eeprom. // EEPROM.write(0,1); mySerial.begin(9600); delay(500); // The next line configures the BT-04 (BT-06) Module to NOT report connection status. mySerial.write("\r\nAT+ENABLEIND0\r\n"); delay(100); ClearRXbuffer(); // change the name of the BT-04 (BT-06) device, this will not work for HC-06 mySerial.write("AT+NAMELichtkrant01\r\n"); delay(100); ClearRXbuffer(); LK.begin(); LK.displayClear(); LK.displaySuspend(false); LK.displayText(curMessage, scrollAlign, scrollSpeed, scrollPause, scrollEffect, scrollEffect); // Get the last message from EEPROM getMessageFromEeprom(); } void loop() { readSerial(); if (LK.displayAnimate()) { if (newMessageAvailable) { strcpy(curMessage, newMessage); newMessageAvailable = false; storeMessageInEeprom(); } LK.displayReset(); } } void readSerial(void) { static char *cp = newMessage; while (mySerial.available()) { *cp = (char)mySerial.read(); if ( (*cp == '\r') || (*cp == '\n') || (cp - newMessage >= BUF_SIZE-2)) // end of message character or full buffer { *cp = '\0'; // end the string cp = newMessage; newMessageAvailable = true; mySerial.print("Nieuwe Boodschap = "); mySerial.println(newMessage); ClearRXbuffer(); } else // move char pointer to next position cp++; } } void storeMessageInEeprom(){ // Store the message in EEPROM EEPROM.write(0,251); int i=0; char c=curMessage[i]; while (c !=0){ EEPROM.write(i+1,c); i++; c=curMessage[i]; } EEPROM.write(i+1,0); } void getMessageFromEeprom(){ if (EEPROM.read(0)!=251){ strcpy(curMessage, "Please send new message over Bluetooth"); newMessage[0] = '\0'; } else { int i=0; char c = EEPROM.read(i+1); while (c!=0){ curMessage[i++]=c; c = EEPROM.read(i+1); } curMessage[i] = '\0'; newMessageAvailable=false; } } void ClearRXbuffer(){ while (mySerial.available()){ char c=mySerial.read(); delay(5); } }

De Android APP

Ik gebruik de volgende Android app op mijn tablet (of telefoon).
Link naar Google Play



Apple's iOS kan niet verbinden met de gebruikte bluetooth module, dit werkt dus alleen met Android.

De werking van de app spreekt voor zich, maar in de video laat ik het ook nog stap voor stap zien

Bekijk de video

In de video vertel ik er meer over... kijk, like, en subscribe!

Update 2019 !

De gebruikte libraries (MD_Parola en MD_MAX72xx) worden zo nu en dan ge-update, en ze zijn dan niet altijd compatible met de eerdere versies. Als gevolg werkt dan mijn sketch niet meer.
Om dat probleem te omzeilen heb ik een nieuwe sketch gemaakt. Deze sketch maakt nog steeds gebruik van een paar libraries maar deze zijn inmiddels zo goed als uitontwikkeld. Ik verwacht dat deze sketch lang zal blijven werken.
De nieuwe sketch is behoorlijk lang omdat de aansturing van de lichtkrant (de led matrix driver) en het lettertype nu allemaal in de sketch zit, eerder zat dat in externe libraries maar dat wil ik zoveel mogelijk vermijden.

De update Video

De nieuwe software sketch

28 mei 2020: Update, verbeterde sketch.
// --------------------------------------------------------------------------- // --------------------------------------------------------------------------- // SETUP: // Width of your display (number of leds): const int LEDMATRIX_WIDTH = 64; // Initial text: // This char array holds char curMessage[] = "Please send a new message over Bluetooth !\0 "; // Scroll Speed: (1 to 10) int scrollSpeed = 4; // Reverse order? Change this if your display seems reversed bool modReverse = false; // Slave select pin on Arduino, also known as Chip select uint8_t ssPin = 10; // --------------------------------------------------------------------------- // --------------------------------------------------------------------------- // This code is a combination of // 1) https://github.com/bartoszbielawski/LEDMatrixDriver/blob/master/examples/MarqueeText/MarqueeText.ino // 2) the ledMatrixDriver library (I copied lots of code from that lib into this sketch) // 3) My own code #include <SPI.h> #include <SoftwareSerial.h> #include <EEPROM.h> #define CHAR_WIDTH 5 #define SPACE_WIDTH 2 #define CHAR_SPACING 1 #define BUF_SIZE 75 // Use softserial for the bluetooth module SoftwareSerial mySerial(2, 3); const byte font[] PROGMEM= { B00000000, B00000000, B00000000, B00000000, B00000000 , /* 032 = */ B01101111, B01101111, B00000000, B00000000, B00000000 , /* 033 = ! */ B00000011, B00000000, B00000011, B00000000, B00000000 , /* 034 = " */ B00101000, B01111100, B00101000, B01111100, B00101000 , /* 035 = # */ B00100100, B00101010, B01111111, B00101010, B00010010 , /* 036 = $ */ B01100011, B00010011, B00001000, B01100100, B01100011 , /* 037 = % */ B00111010, B01000101, B01000101, B00111010, B01001000 , /* 038 = & */ B00000011, B00000000, B00000000, B00000000, B00000000 , /* 039 = ' */ B00011100, B00100010, B01000001, B00000000, B00000000 , /* 040 = ( */ B01000001, B00100010, B00011100, B00000000, B00000000 , /* 041 = ) */ B00000111, B00000111, B00000111, B00000000, B00000000 , /* 042 = * */ B00010000, B00010000, B01111100, B00010000, B00010000 , /* 043 = + */ B01110000, B00110000, B00000000, B00000000, B00000000 , /* 044 = , */ B00001000, B00001000, B00001000, B00001000, B00001000 , /* 045 = - */ B01100000, B01100000, B00000000, B00000000, B00000000 , /* 046 = . */ B01100000, B00010000, B00001000, B00000100, B00000011 , /* 047 = / */ B00111110, B01010001, B01001001, B01000101, B00111110 , /* 048 = 0 */ B01000010, B01111111, B01000000, B00000000, B00000000 , /* 049 = 1 */ B01000010, B01100001, B01010001, B01001001, B01000110 , /* 050 = 2 */ B00100001, B01000001, B01000101, B01001011, B00110001 , /* 051 = 3 */ B00011000, B00010100, B00010010, B01111111, B00010000 , /* 052 = 4 */ B00100111, B01000101, B01000101, B01000101, B00111001 , /* 053 = 5 */ B00111100, B01001010, B01001001, B01001001, B00110000 , /* 054 = 6 */ B00000001, B00000001, B01111001, B00000101, B00000011 , /* 055 = 7 */ B00110110, B01001001, B01001001, B01001001, B00110110 , /* 056 = 8 */ B00000110, B01001001, B01001001, B00101001, B00011110 , /* 057 = 9 */ B00110110, B00110110, B00000000, B00000000, B00000000 , /* 058 = : */ B01110110, B00110110, B00000000, B00000000, B00000000 , /* 059 = ; */ B00010000, B00101000, B01000100, B00000000, B00000000 , /* 060 = < */ B00010100, B00010100, B00010100, B00010100, B00010100 , /* 061 = = */ B01000100, B00101000, B00010000, B00000000, B00000000 , /* 062 = > */ B00000010, B00000001, B01010001, B00001001, B00000110 , /* 063 = ? */ B00111110, B01000001, B01011101, B01010101, B01011110 , /* 064 = @ */ B01111110, B00010001, B00010001, B00010001, B01111110 , /* 065 = A */ B01111111, B01001001, B01001001, B01001001, B00110110 , /* 066 = B */ B00111110, B01000001, B01000001, B01000001, B00100010 , /* 067 = C */ B01111111, B01000001, B01000001, B01000001, B00111110 , /* 068 = D */ B01111111, B01001001, B01001001, B01001001, B01000001 , /* 069 = E */ B01111111, B00001001, B00001001, B00001001, B00000001 , /* 070 = F */ B00111110, B01000001, B01001001, B01001001, B01111010 , /* 071 = G */ B01111111, B00001000, B00001000, B00001000, B01111111 , /* 072 = H */ B01000001, B01111111, B01000001, B00000000, B00000000 , /* 073 = I */ B00100000, B01000000, B01000001, B00111111, B00000001 , /* 074 = J */ B01111111, B00001000, B00010100, B00100010, B01000001 , /* 075 = K */ B01111111, B01000000, B01000000, B01000000, B01000000 , /* 076 = L */ B01111111, B00000010, B00000100, B00000010, B01111111 , /* 077 = M */ B01111111, B00000010, B00011100, B00100000, B01111111 , /* 078 = N */ B00111110, B01000001, B01000001, B01000001, B00111110 , /* 079 = O */ B01111111, B00010001, B00010001, B00010001, B00001110 , /* 080 = P */ B00111110, B01000001, B01010001, B01100001, B01111110 , /* 081 = Q */ B01111111, B00001001, B00011001, B00101001, B01000110 , /* 082 = R */ B00100110, B01001001, B01001001, B01001001, B00110010 , /* 083 = S */ B00000001, B00000001, B01111111, B00000001, B00000001 , /* 084 = T */ B00111111, B01000000, B01000000, B01000000, B00111111 , /* 085 = U */ B00011111, B00100000, B01000000, B00100000, B00011111 , /* 086 = V */ B00111111, B01000000, B00110000, B01000000, B00111111 , /* 087 = W */ B01100011, B00010100, B00001000, B00010100, B01100011 , /* 088 = X */ B00000111, B00001000, B01110000, B00001000, B00000111 , /* 089 = Y */ B01100001, B01010001, B01001001, B01000101, B01000011 , /* 090 = Z */ B01111111, B01000001, B01000001, B00000000, B00000000 , /* 091 = [ */ B00000011, B00000100, B00001000, B00010000, B01100000 , /* 092 = \ */ B01000001, B01000001, B01111111, B00000000, B00000000 , /* 093 = ] */ B00000100, B00000010, B00000001, B00000010, B00000100 , /* 094 = ^ */ B01000000, B01000000, B01000000, B01000000, B01000000 , /* 095 = _ */ B00000011, B00000000, B00000000, B00000000, B00000000 , /* 096 = ' */ B00100000, B01010100, B01010100, B01010100, B01111000 , /* 097 = a */ B01111111, B00101000, B01000100, B01000100, B00111000 , /* 098 = b */ B00111000, B01000100, B01000100, B01000100, B00101000 , /* 099 = c */ B00111000, B01000100, B01000100, B00101000, B01111111 , /* 100 = d */ B00111000, B01010100, B01010100, B01010100, B00011000 , /* 101 = e */ B00000100, B01111110, B00000101, B00000001, B00000010 , /* 102 = f */ B00001000, B01010100, B01010100, B01010100, B00111100 , /* 103 = g */ B01111111, B00000100, B00000100, B00000100, B01111000 , /* 104 = h */ B01000100, B01111101, B01000000, B00000000, B00000000 , /* 105 = i */ B00100000, B01000000, B01000100, B00111101, B00000000 , /* 106 = j */ B01111111, B00010000, B00010000, B00101000, B01000100 , /* 107 = k */ B01000001, B01111111, B01000000, B00000000, B00000000 , /* 108 = l */ B01111100, B00000100, B01111100, B00000100, B01111000 , /* 109 = m */ B01111100, B00001000, B00000100, B00000100, B01111000 , /* 110 = n */ B00111000, B01000100, B01000100, B01000100, B00111000 , /* 111 = o */ B01111100, B00100100, B00100100, B00100100, B00011000 , /* 112 = p */ B00011000, B00100100, B00100100, B00100100, B01111100 , /* 113 = q */ B01111100, B00001000, B00000100, B00000100, B00001000 , /* 114 = r */ B01001000, B01010100, B01010100, B01010100, B00100000 , /* 115 = s */ B00000100, B00111110, B01000100, B01000000, B00100000 , /* 116 = t */ B00111100, B01000000, B01000000, B00100000, B01111100 , /* 117 = u */ B00011100, B00100000, B01000000, B00100000, B00011100 , /* 118 = v */ B00111100, B01000000, B00110000, B01000000, B00111100 , /* 119 = w */ B01000100, B00101000, B00010000, B00101000, B01000100 , /* 120 = x */ B00000100, B01001000, B00110000, B00001000, B00000100 , /* 121 = y */ B01000100, B01100100, B01010100, B01001100, B01000100 , /* 122 = z */ B00001000, B00110110, B01000001, B00000000, B00000000 , /* 123 = */ B01111111, B00000000, B00000000, B00000000, B00000000 , /* 124 = | */ B01000001, B00110110, B00001000, B00000000, B00000000 , /* 125 = */ B00011000, B00000100, B00001000, B00010000, B00001100 , /* 126 = ~ */ B00000000, B00000000, B00000000, B00000000, B00000000 , /* 127 = */ B01111011, B01111011, B00000000, B00000000, B00000000 , /* 128 = ¡ */ B00011100, B00100010, B01111111, B00100010, B00010100 , /* 129 = ¢ */ B01001000, B01111110, B01001001, B01001001, B01000010 , /* 130 = £ */ B00100010, B00011100, B00010100, B00011100, B00100010 , /* 131 = ¤ */ B00000001, B00101010, B01111100, B00101010, B00000001 , /* 132 = ¥ */ B01110111, B00000000, B00000000, B00000000, B00000000 , /* 133 = ¦ */ B01001010, B01010101, B01010101, B01010101, B00101001 , /* 134 = § */ B00000001, B00000000, B00000001, B00000000, B00000000 , /* 135 = ¨ */ B00100010, B01001001, B01010101, B01010101, B00100010 , /* 136 = © */ B00000110, B00001001, B00001001, B00000110, B00000000 , /* 137 = ª */ B00010000, B00101000, B01010100, B00101000, B01000100 , /* 138 = « */ B00001000, B00001000, B00011000, B00000000, B00000000 , /* 139 = ¬ */ B00000000, B00000000, B00000000, B00000000, B00000000 , /* 140 = ­ */ B00000010, B01111101, B00010101, B01101001, B00000010 , /* 141 = ® */ B00000001, B00000001, B00000001, B00000001, B00000001 , /* 142 = ¯ */ B00000111, B00000101, B00000111, B00000000, B00000000 , /* 143 = ° */ B01001000, B01011100, B01001000, B00000000, B00000000 , /* 144 = ± */ B00011001, B00010101, B00010101, B00010010, B00000000 , /* 145 = ² */ B00010001, B00010101, B00010101, B00001010, B00000000 , /* 146 = ³ */ B00000010, B00000001, B00000000, B00000000, B00000000 , /* 147 = ´ */ B01111100, B00100000, B00100000, B00111100, B00100000 , /* 148 = µ */ B00000110, B00001111, B01111111, B00000001, B01111111 , /* 149 = ¶ */ B00001100, B00001100, B00000000, B00000000, B00000000 , /* 150 = · */ B01000000, B00000000, B00000000, B00000000, B00000000 , /* 151 = ¸ */ B00010010, B00011111, B00010000, B00000000, B00000000 , /* 152 = ¹ */ B00001110, B00010001, B00010001, B00011111, B00000000 , /* 153 = º */ B01000100, B00101000, B01010100, B00101000, B00010000 , /* 154 = » */ B01110111, B00001000, B00110100, B00101010, B01111101 , /* 155 = ¼ */ B01110111, B00001000, B01010100, B01101010, B01010001 , /* 156 = ½ */ B01010101, B00101110, B00010000, B00101010, B01111101 , /* 157 = ¾ */ B00110000, B01001000, B01000101, B01000000, B00100000 , /* 158 = ¿ */ B01111000, B00100101, B00100110, B00100100, B01111000 , /* 159 = À */ B01111000, B00100100, B00100110, B00100101, B01111000 , /* 160 = Á */ B01111000, B00100110, B00100101, B00100110, B01111000 , /* 161 = Â */ B01111001, B00100110, B00100101, B00100110, B01111000 , /* 162 = Ã */ B01111000, B00100101, B00100100, B00100101, B01111000 , /* 163 = Ä */ B01111000, B00100111, B00100101, B00100111, B01111000 , /* 164 = Å */ B01111100, B00010010, B01111111, B01001001, B01000001 , /* 165 = Æ */ B00011110, B00100001, B01100001, B00100001, B00010010 , /* 166 = Ç */ B01111100, B01010101, B01010110, B01010100, B01000100 , /* 167 = È */ B01111100, B01010100, B01010110, B01010101, B01000100 , /* 168 = É */ B01111100, B01010110, B01010101, B01010110, B01000100 , /* 169 = Ê */ B01111100, B01010101, B01010100, B01010101, B01000100 , /* 170 = Ë */ B01000101, B01111110, B01000100, B00000000, B00000000 , /* 171 = Ì */ B01000100, B01111110, B01000101, B00000000, B00000000 , /* 172 = Í */ B01000110, B01111101, B01000110, B00000000, B00000000 , /* 173 = Î */ B01000101, B01111100, B01000101, B00000000, B00000000 , /* 174 = Ï */ B00001000, B01111111, B01001001, B01000001, B00111110 , /* 175 = Ð */ B01111101, B00001010, B00010001, B00100010, B01111100 , /* 176 = Ñ */ B00111000, B01000101, B01000110, B01000100, B00111000 , /* 177 = Ò */ B00111000, B01000100, B01000110, B01000101, B00111000 , /* 178 = Ó */ B00111000, B01000110, B01000101, B01000110, B00111000 , /* 179 = Ô */ B00111010, B01000101, B01000110, B01000101, B00111000 , /* 180 = Õ */ B00111000, B01000101, B01000100, B01000101, B00111000 , /* 181 = Ö */ B00100010, B00010100, B00001000, B00010100, B00100010 , /* 182 = × */ B00111110, B01100001, B01011101, B01000011, B00111110 , /* 183 = Ø */ B00111100, B01000001, B01000010, B01000000, B00111100 , /* 184 = Ù */ B00111100, B01000000, B01000010, B01000001, B00111100 , /* 185 = Ú */ B00111100, B01000010, B01000001, B01000010, B00111100 , /* 186 = Û */ B00111100, B01000001, B01000000, B01000001, B00111100 , /* 187 = Ü */ B00000110, B00001000, B01110010, B00001001, B00000110 , /* 188 = Ý */ B01111111, B00100010, B00100010, B00100010, B00011100 , /* 189 = Þ */ B01111110, B00000001, B01001001, B01001101, B00110010 , /* 190 = ß */ B00100000, B01010101, B01010110, B01010100, B01111000 , /* 191 = à */ B00100000, B01010100, B01010110, B01010101, B01111000 , /* 192 = á */ B00100000, B01010110, B01010101, B01010110, B01111000 , /* 193 = â */ B00100000, B01010101, B01010110, B01010101, B01111010 , /* 194 = ã */ B00100000, B01010101, B01010100, B01010101, B01111000 , /* 195 = ä */ B00100000, B01010111, B01010101, B01010111, B01111000 , /* 196 = å */ B00100000, B01010100, B01111100, B01010100, B01001000 , /* 197 = æ */ B00011000, B00100100, B01100100, B00100100, B00010100 , /* 198 = ç */ B00111000, B01010101, B01010110, B01010100, B00011000 , /* 199 = è */ B00111000, B01010100, B01010110, B01010101, B00011000 , /* 200 = é */ B00111000, B01010110, B01010101, B01010110, B00011000 , /* 201 = ê */ B00111000, B01010101, B01010100, B01010101, B00011000 , /* 202 = ë */ B01000101, B01111110, B01000000, B00000000, B00000000 , /* 203 = ì */ B01000100, B01111110, B01000001, B00000000, B00000000 , /* 204 = í */ B01000110, B01111101, B01000010, B00000000, B00000000 , /* 205 = î */ B01000101, B01111100, B01000001, B00000000, B00000000 , /* 206 = ï */ B00110000, B01001001, B01001001, B01001010, B00111101 , /* 207 = ð */ B01111100, B00001001, B00000110, B00000101, B01111010 , /* 208 = ñ */ B00111000, B01000101, B01000110, B01000100, B00111000 , /* 209 = ò */ B00111000, B01000100, B01000110, B01000101, B00111000 , /* 210 = ó */ B00111000, B01000110, B01000101, B01000110, B00111000 , /* 211 = ô */ B00111000, B01000101, B01000110, B01000101, B00111010 , /* 212 = õ */ B00111000, B01000101, B01000100, B01000101, B00111000 , /* 213 = ö */ B00001000, B00101010, B00001000, B00000000, B00000000 , /* 214 = ÷ */ B00111000, B01100100, B01010100, B01001100, B00111000 , /* 215 = ø */ B00111100, B01000001, B01000010, B00100000, B01111100 , /* 216 = ù */ B00111100, B01000000, B01000010, B00100001, B01111100 , /* 217 = ú */ B00111100, B01000010, B01000001, B00100010, B01111100 , /* 218 = û */ B00111100, B01000001, B01000000, B00100001, B01111100 , /* 219 = ü */ B00000100, B01001000, B00110010, B00001001, B00000100 , /* 220 = ý */ B01111111, B00101000, B00101000, B00101000, B00010000 , /* 221 = þ */ B00000100, B01001001, B00110000, B00001001, B00000100 /* 222 = ÿ */ }; const static uint16_t ENABLE = 0x0C00; const static uint16_t TEST = 0x0F00; const static uint16_t INTENSITY = 0x0A00; const static uint16_t SCAN_LIMIT = 0x0B00; const static uint16_t DECODE = 0x0900; const uint8_t N = LEDMATRIX_WIDTH / 8; uint8_t* frameBuffer = new uint8_t[LEDMATRIX_WIDTH ]; int x = LEDMATRIX_WIDTH, y = 0; uint32_t scrollTimerStamp = 0; int txtLen ; /*length of text in bytes*/ int txtWidth ; /*width of text in pixels*/ int scrollDelay = 100 / scrollSpeed; char newMessage[BUF_SIZE]; bool newMessageAvailable = false; void setup() { // Enable the next line to clear the message from eeprom at startup. // EEPROM.write(0,1); pinMode(ssPin, OUTPUT); digitalWrite(ssPin, HIGH); SPI.begin(); // clear the framebuffer memset(frameBuffer, 0, 8*N); sendCommand(INTENSITY | 0); sendCommand(TEST); sendCommand(DECODE); sendCommand(SCAN_LIMIT | 7); sendCommand(ENABLE | 1); sendCommand(INTENSITY | 3); mySerial.begin(9600); delay(500); // The next line configures the BT-04 (BT-06) Module to NOT report connection status. mySerial.write("\r\nAT+ENABLEIND0\r\n"); delay(100); ClearRXbuffer(); // change the name of the BT-04 (BT-06) device, this will not work for HC-06 // mySerial.write("AT+NAMELichtkrant01\r\n"); delay(100); ClearRXbuffer(); // Get the last message from EEPROM getMessageFromEeprom(); } void loop() { readSerial(); if (newMessageAvailable) { strcpy(curMessage, newMessage); // clear the framebuffer memset(frameBuffer, 0, 8*N); refreshDisplay(); x=LEDMATRIX_WIDTH; newMessageAvailable = false; storeMessageInEeprom(); } if (millis() < scrollTimerStamp) return; scrollTimerStamp = scrollDelay + millis(); txtLen = sizeof(curMessage); txtWidth = getTextWidth(curMessage); setText(curMessage, x, 0); refreshDisplay(); // shift the position if (x-- < -txtWidth) x = LEDMATRIX_WIDTH; } void readSerial(void) { static char *cp = newMessage; while (mySerial.available()) { *cp = (char)mySerial.read(); if ( (*cp == '\r') || (*cp == '\n') || (cp - newMessage >= BUF_SIZE-2)) // end of message character or full buffer { *cp = '\0'; // end the string cp = newMessage; newMessageAvailable = true; mySerial.print("Nieuwe Boodschap = "); mySerial.println(newMessage); ClearRXbuffer(); } else { // move char pointer to next position cp++; } } } void storeMessageInEeprom(){ // Store the message in EEPROM EEPROM.write(0,251); int i=0; char c=curMessage[i]; while (c !=0){ EEPROM.write(i+1,c); i++; c=curMessage[i]; } EEPROM.write(i+1,0); } void getMessageFromEeprom(){ if (EEPROM.read(0)!=251){ newMessage[0] = '\0'; } else { int i=0; char c = EEPROM.read(i+1); while (c!=0){ curMessage[i++]=c; c = EEPROM.read(i+1); } curMessage[i] = '\0'; newMessageAvailable=false; } } void ClearRXbuffer(){ while (mySerial.available()){ char c=mySerial.read(); delay(5); } } // setText - writes text of the given length for the given position, to the driver buffer. void setText(char* text, int x, int y) { int pos = x; for (int i = 0; i < strlen(text); i ++) { byte asc = text[i] - 32; // stop if char is outside visible area if (pos > LEDMATRIX_WIDTH) return; int c_Width = getCharWidth(asc); // only draw if char is visible if (pos > -8) { setWChar(asc, pos, y, c_Width); } pos += c_Width + CHAR_SPACING; } } // writes char to the driver buffer by passing position (x,y), char width and char start column void setWChar(int chrin, int x, int y, int twidth) { byte bitMask = B00000001; for (int iX = 0; iX < twidth + (CHAR_SPACING); iX++) { for (int iY = 0; iY < 8; iY++) { if (iX > twidth - 1) { setPixel(x + iX, y + iY, 0); } else { setPixel(x + iX, y + iY, bitRead(pgm_read_byte(&font[(chrin*5) + iX]),iY)); } bitMask <<= 1; } bitMask = 1; } } // calculates character width without whitespace. int getCharWidth(int asc) { if (asc == 0) { return SPACE_WIDTH; } else { int c_Width = 0; for (int c = 0; c < CHAR_WIDTH; c++) { if (pgm_read_byte(&font[(asc * 5) + c]) != 0) c_Width++; } //give extra spacing for . if (asc == 14) c_Width++; return c_Width; } } // calculates the text width using variable character width and CHAR_SPACING and int getTextWidth(char* text) { int t_Width = 0; for (int i = 0; i < strlen(text); i++) { byte asc = text[i] - 32; t_Width += getCharWidth(asc) + CHAR_SPACING; } return t_Width; } void setPixel(int16_t x, int16_t y, bool enabled) { uint8_t* p = getBufferPtr(x, (modReverse) ? 7 - y : y); if (!p) return; uint16_t b = (modReverse) ? (x & 7) : 7 - (x & 7); //bit if (enabled) *p |= (1 << b); else *p &= ~(1 << b); } bool getPixel(int16_t x, int16_t y) { uint8_t* p = getBufferPtr(x, (modReverse) ? 7 - y : y); if (!p) return false; uint16_t b = (modReverse) ? (x & 7) : 7 - (x & 7); //bit return *p & (1 << b); } void sendCommand(uint16_t command) { SPI.beginTransaction(SPISettings(5000000, MSBFIRST, SPI_MODE0)); digitalWrite(ssPin, 0); for (uint8_t i = 0; i < N; ++i) { SPI.transfer16(command); } digitalWrite(ssPin, 1); SPI.endTransaction(); } void displayRow(uint8_t row) { SPI.beginTransaction(SPISettings(5000000, MSBFIRST, SPI_MODE0)); digitalWrite(ssPin, 0); for (uint16_t d = 0; d < N; d++) { uint16_t cmd = ((row + 1) << 8) | frameBuffer[d + row * N]; SPI.transfer16(cmd); } digitalWrite(ssPin, 1); SPI.endTransaction(); } uint8_t* getBufferPtr(int16_t x, int16_t y) { if ((y >= 8) or (y < 0)) return nullptr; if ((x >= (8 * N)) or (x < 0)) return nullptr; uint16_t B = x >> 3; //byte return frameBuffer + y * N + B; } void refreshDisplay() { for (uint8_t y = 0; y < 8; y++) { displayRow(y); } }