Peeking at Espruino Board Timers 2, 3, 4, and 5

CountT5A1Poke.js
Program that looks at timer registers to test timer 5 in
External clock source mode 1 see page 377,378 of RM0008
Reference manual

Sets up a PWM on Pin B0, connect to pin A1 channel 2 of timer 5.

analogWrite(B0,0.5,{ freq : 1000 });

//setup pins A0, A1, A2, A3
A0.mode('input');
A1.mode('input');
A2.mode('input');
A3.mode('input');

//timer 5 clock
var RCCbase=0x40021000;
var APB1ENR=RCCbase+0x1c;
var APB1RST=RCCbase+0x10;
var APB2ENR=RCCbase+0x18;

//turn on timer 5 clock
 poke8(APB1ENR,(peek8(APB1ENR)&0xf7)|0x08);

//reset timer 5
 poke8(APB1RST,(peek8(APB1RST)&0xf7)|0x08);
 poke8(APB1RST,(peek8(APB1RST)^0x08));

//disable timer 5
  poke32(TIM5+CR1,0x80);

//setup timer 5
poke16(TIM5+CCMR1,0x0100);
poke16(TIM5+CCER,0x0000); //0;
poke16(TIM5+SMCR,0x0067);//0x0067);
//Preload timer
poke32(TIM5+EGR,1);
//Enable timer 5
poke32(TIM5+CR1,0x81); //10Hz

//Display timers
for(var i=0; i in timers;i++){
 if(isTimerEnabled(timers[i])) 
  showTimer(timers[i].t,16,i);
}//next i

console.log("Display Count");
for(var i=0;i<1000;i++)
  console.log("CNT="+peek32(TIM5+CNT));

Try changing the frequency of the PWM on pin B0.

1 Attachment

• CountT5A1Poke.js