Interfacing ps2 keyboard with esp8266

Projects Programming
1

I want to interface ps2 keyboard with esp8266 but cant find any library so it tried a code and it worked 50% because when i start typing after 20 to 25 letters the esp8266 gets RESETS.
The serial shows this error

ets Jan  8 2013,rst cause:4, boot mode:(3,6)

wdt reset
load 0x4010f000, len 3424, room 16 
tail 0
chksum 0x2e
load 0x3fff20b8, len 40, room 8 
tail 0
chksum 0x2b
csum 0x2b
v00042040

here is my code

char ScancodeToASCII[2][128] = {
  { 0,0,0,0,0,0,0,0,         0,0,0,0,0,9,94,0,         0,0,0,0,0,113,49,0,       0,0,121,115,97,119,50,0,    // w/o SHIFT or ALT(GR)
    0,99,120,100,101,52,51,0,0,32,118,102,116,114,53,0,0,110,98,104,103,122,54,0,0,0,109,106,117,55,56,0,
    0,44,107,105,111,48,57,0,0,46,45,108,148,112,0,0,  0,0,132,0,129,96,0,0,     0,0,10,43,0,35,0,0,
    0,60,0,0,0,0,8,0,        0,0,0,0,0,0,0,0,          0,0,0,0,0,0,27,0,         0,0,0,0,0,0,0,0  },
  { 0,0,0,0,0,0,0,0,         0,0,0,0,0,0,248,0,        0,0,0,0,0,81,33,0,        0,0,89,83,65,87,34,0,       // with SHIFT
    0,67,88,68,69,36,0,0,    0,0,86,70,84,82,37,0,     0,78,66,72,71,90,38,0,    0,0,77,74,85,47,40,0,
    0,59,75,73,79,61,41,0,   0,58,95,76,153,80,63,0,   0,0,142,0,154,0,0,0,      0,0,0,42,0,39,0,0,
    0,62,0,0,0,0,0,0,        0,0,0,0,0,0,0,0,          0,0,0,0,0,0,0,0,          0,0,0,0,0,0,0,0  } };

volatile bool shiftIsActive = false;      
volatile bool nextIsReleased = false;    

void setup() {
  pinMode(5, INPUT_PULLUP);  //  connected to D1 (GPIO5)
  pinMode(4, INPUT_PULLUP);  //  connected to D2 (GPIO4)
  attachInterrupt(digitalPinToInterrupt(4), ISRFunction, CHANGE);
  Serial.begin(115200);
}

void loop() {
  // Your main code, if any, can go here
}

ICACHE_RAM_ATTR void ISRFunction() {
  int val = 0;
  for (int i = 0; i < 11; i++) {
    while (digitalRead(5) == HIGH);  
    val |= digitalRead(4) << i;      
    while (digitalRead(5) == LOW);
  }
  val = (val >> 1) & 255;

  switch (val) {
    case 18: case 89: shiftIsActive = !nextIsReleased; nextIsReleased = false; break;  
    case 240: nextIsReleased = true; break;  
    default:  
      if (!nextIsReleased) {  // is it a 'key pressed' event?
        Serial.print(ScancodeToASCII[shiftIsActive][val & 127]);  
      }
      nextIsReleased = false;
      break;
  }
}
2

I use PS2Keyboard.h.
I built the keyboard CW keyer from the ARRL book Arduino of ham radio". Works perfectly!

3

You use PS2Keyboard.h for ESP8266?

first of all, The library says it is not for ESP8266 and when I try to use it then it continues reset the esp8266. if you use it so plz send give the library information plz.
thanks

4

I just reviewed my copy of the library and see it currently only supports the AVR series for interrupts. Perhaps that is where the problem lies. Looks like other sets of interrupts could be added.

5

Yes, the problem lies in the interrupt, bcz the code I am using is working for 20-25 keys pressed by the keyboard after that the esp8266 gets reset. Can you help in that.
Thanks

6

No, but you can help yourself.
Did you look at the reason the the reset? Is says the WDT expired and that caused the reset. Do you know there is a timer that watches over your interrupt code and if you do not exit your interrupt code in a timely manner, the timer will cause the reset.
So rethink your program and avoid any interrupt code that does not return as quickly as possible.

7

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