Silicon Laboratories Stepper Machine Manual do Utilizador descarregar pdf (Página 34)

AN155

34 Rev. 1.1

}

//-----------------------------------------------------------------------------

void uartISR(void) interrupt 4 // main UART interrupt service routine

{

char dummy;

signed char i;

// Who done it?

if(RI0 == 1) // Was it the receiver?

{

RI0 = 0; // yep, clear receiver flag

// if not full

if (readCount != READ_BUFFER_SIZE)

{

readBuffer[readIndex]= SBUF0; // read char from UART

readIndex++; // increment index

if (readIndex == READ_BUFFER_SIZE)

readIndex = 0; // fix if out of range

readCount++; // one more in the buffer

}

else

{

dummy = SBUF0; // drop characters dummy!

}

if(TI0 == 1) // Was it the transmitter?

{

TI0 = 0; // yep, clear transmitter flag

if (writeCount>0) // if not empty

{

i = writeIndex - writeCount; // calculate where to get it

if (i < 0) // fix if out of range

i+=WRITE_BUFFER_SIZE;

SBUF0 = writeBuffer[i]; // write character to UART

writeCount--; // one less in the buffer

}

else

{

TX_Idle = 1; // set idle flag when empty

}

//-----------------------------------------------------------------------------

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Silicon Laboratories Stepper Machine Manual do Utilizador Página 34