Master espruinio: Wii Nunchuk AND Slave espruino: L298N motor controller wireless with 2x NRF24L01P

This project is a wireless controlled 2 wheeled robot.

Master hardware:
-Espruino 1v54

• Wii nunchuck (B10, B11)
  

• NRF24L01P wireless chip
  
  Master software code:

  var btn_state=false;
  var read_wii,wii_data,wii_data_new;
  SPI1.setup({sck:A5, miso:A6, mosi:A7});
  //I2C1.setup({scl:B6,sda:B7}); // slave
  I2C2.setup({scl:B10,sda:B11}); //master
  var nrf = require("NRF24L01P").connect( SPI1, B0, B1 );
  var wii = require("wii_nunchuck").connect(I2C2);
  function onInit() {
  nrf.init([0,0,0,0,2], [0,0,0,0,1]);
  wii_data_new=wii_data;
  }
  onInit();
  setInterval(function() {
  nrf.masterHandler();
  }, 50);
  function start_wii_read(){
  read_wii = setInterval(function(){
  //console.log(JSON.Stringify(wii.read()));
  wii_data_new=wii.read();
  //console.log(wii_data.joy);
  if(wii_data.btn.z!==wii_data_new.btn.z){
    if(wii_data_new.btn.z){ wii_btn_z_press(); } else { wii_btn_z_release(); }
  }
  if(wii_data.btn.c!==wii_data_new.btn.c){
    if(wii_data_new.btn.c){ wii_btn_c_press(); } else { wii_btn_c_release(); }
  }
  wii_data=wii_data_new;
  },20);
  }
  function stop_wii_read(){
  	clearInterval(start_read);
  }
  
  function wii_btn_z_press(){
  //console.log("Z");
  LED2.set();
  nrf.sendCommand("MOTOR(0,1,0,1);",function(r){});
  //nrf.sendCommand("LED2.set();",function(r){});
  }
  function wii_btn_c_press(){
  LED1.set();
  nrf.sendCommand("MOTOR(1,0,1,0);",function(r){});
  //console.log("C");
  }
  function wii_btn_z_release(){
  LED2.reset();
  nrf.sendCommand("MOTOR(0,0,0,0);",function(r){});
  //nrf.sendCommand("LED2.reset();",function(r){});
  //console.log("stopZ");
  }
  function wii_btn_c_release(){
  //console.log("stopC");
  LED1.reset();
  nrf.sendCommand("MOTOR(0,0,0,0);",function(r){});
  //nrf.sendCommand("LED1.reset();",function(r){});
  //console.log("stopC");
  }
  
  function led_on() {
  	LED3.set();
  }
  
  function led_off() {
  	LED3.reset();
  }
  
  wii_data=wii.read();
  
  btn_watch_press = setWatch(function(){
  	if(!btn_state){
  		led_on();
      start_wii_read();
  } else {
  		led_off();
      stop_wii_read();
  	}
  	btn_state=!btn_state;
  },BTN,{repeat:true,edge:'rising'});
  btn_watch_release = setWatch(function(){
  	console.log(btn_state);
  },BTN,{repeat:true,edge:'falling'});
  

Slave hardware:
-Espruino 1v53
-L298N motor controller board with 2 hacked micro servo motor used as simple DC motor
-NRF24L01P wireless chip
-6xAA wired in series rechargeable 2000mAh battery

Slave software code:

/* NRF24L01P - wireless */
SPI1.setup({sck:A5, miso:A6, mosi:A7});
var nrf = require("NRF24L01P").connect( SPI1, B0, B1 );
function onInit() {
  nrf.init([0,0,0,0,1], [0,0,0,0,2]);
}
onInit();
setInterval(function() {
  nrf.slaveHandler();
}, 50);

/* motor controller */
var MOTOR_PINS=[C9,C8,C7,C6];
function MOTOR(val1,val2,val3,val4){
  digitalWrite(MOTOR_PINS[0],parseInt(val1));
  digitalWrite(MOTOR_PINS[1],parseInt(val2));
  digitalWrite(MOTOR_PINS[2],parseInt(val3));
  digitalWrite(MOTOR_PINS[3],parseInt(val4));
}

Sometimes NRF24L01P on master trow an error: TX not received 30

Wii nunchuk I2C port BUSY. Got error message when try to save() to master espruino.
Error message:

INTERNAL ERROR: Timeout on I2C Read BUSY
INTERNAL ERROR: Timeout on I2C Read SB
INTERNAL ERROR: Timeout on I2C Read Receive Mode
INTERNAL ERROR: Timeout on I2C Read Receive
INTERNAL ERROR: Timeout on I2C Read Receive
INTERNAL ERROR: Timeout on I2C Read Receive
INTERNAL ERROR: Timeout on I2C Read Receive
INTERNAL ERROR: Timeout on I2C Read Receive
INTERNAL ERROR: Timeout on I2C Read Receive
INTERNAL ERROR: Timeout on I2C Read STOP
at line 1 col 23
{var a=b.readFrom(82,6);b.writeTo(82,0);return{joy:{x:(a[0]-127)/128,y:(a[1]-127)/128},acc:{x:(a[2]-127)/54,y:(a[3]-127)/54,z:(a[4]-127)/54},btn:{z:!(a[5]&1),c:!(a[5]&2)}}}

                   ^

in function "read" called from line 3 col 27
in function called from system
Execution Interrupted during event processing - clearing all timers and watches.

Video:
https://vimeo.com/87922368