@ -38,90 +38,191 @@
# define INCLUDE_FROM_PDITARGET_C
# include "PDITarget.h"
/** Writes a given byte to the attached XMEGA device, using a RS232 frame via software through the
* PDI interface .
*
* \ param [ in ] Byte Byte to send to the attached device
*/
void PDITarget_SendByte ( uint8_t Byte )
# if !defined(PDI_VIA_HARDWARE_USART)
volatile bool IsSending ;
volatile uint16_t DataBits ;
volatile uint8_t BitCount ;
ISR ( TIMER0_COMPA_vect , ISR_BLOCK )
{
uint8_t LogicOneBits = 0 ;
BITBANG_PDICLOCK_PORT ^ = BITBANG_PDICLOCK_MASK ;
// One Start Bit
PDIDATA_LINE_PORT & = ~ PDIDATA_LINE_MASK ;
/* If not sending or receiving, just exit */
if ( ! ( BitCount ) )
return ;
TOGGLE_PDI_CLOCK ;
/* Check to see if the current clock state is on the rising or falling edge */
bool IsRisingEdge = ( BITBANG_PDICLOCK_PORT & BITBANG_PDICLOCK_MASK ) ;
// Eight Data Bits
for ( uint8_t i = 0 ; i < 8 ; i + + )
if ( IsSending & & ! IsRisingEdge )
{
if ( Byte & 0x01 )
{
PDIDATA_LINE_PORT & = ~ PDIDATA_LINE_MASK ;
LogicOneBits + + ;
}
if ( DataBits & 0x01 )
BITBANG_PDIDATA_PORT & = ~ BITBANG_PDIDATA_MASK ;
else
{
PDIDATA_LINE_PORT | = PDIDATA_LINE_MASK ;
}
BITBANG_PDIDATA_PORT | = BITBANG_PDIDATA_MASK ;
Byte > > = 1 ;
DataBits > > = 1 ;
BitCount - - ;
}
else if ( ! IsSending & & IsRisingEdge )
{
/* Wait for the start bit when receiving */
if ( ( BitCount = = BITS_IN_FRAME ) & & ( BITBANG_PDIDATA_PORT & BITBANG_PDIDATA_MASK ) )
return ;
TOGGLE_PDI_CLOCK ;
if ( BITBANG_PDIDATA_PORT & BITBANG_PDIDATA_MASK )
DataBits | = ( 1 < < ( BITS_IN_FRAME - 1 ) ) ;
DataBits > > = 1 ;
BitCount - - ;
}
}
// Even Parity Bit
if ( LogicOneBits & 0x01 )
PDIDATA_LINE_PORT & = ~ PDIDATA_LINE_MASK ;
else
PDIDATA_LINE_PORT | = PDIDATA_LINE_MASK ;
void PDITarget_EnableTargetPDI ( void )
{
/* Set DATA and CLOCK lines to outputs */
BITBANG_PDIDATA_DDR | = BITBANG_PDIDATA_MASK ;
BITBANG_PDICLOCK_DDR | = BITBANG_PDICLOCK_MASK ;
/* Set DATA line high for 90ns to disable /RESET functionality */
BITBANG_PDIDATA_PORT | = BITBANG_PDIDATA_MASK ;
asm volatile ( " NOP " : : ) ;
asm volatile ( " NOP " : : ) ;
/* Fire timer compare ISR every 160 cycles */
OCR0A = 20 ;
TCCR0A = ( 1 < < WGM01 ) ;
TCCR0B = ( 1 < < CS01 ) ;
TIMSK0 = ( 1 < < OCIE0A ) ;
}
TOGGLE_PDI_CLOCK ;
void PDITarget_DisableTargetPDI ( void )
{
/* Set DATA and CLOCK lines to inputs */
BITBANG_PDIDATA_DDR & = ~ BITBANG_PDIDATA_MASK ;
BITBANG_PDICLOCK_DDR & = ~ BITBANG_PDICLOCK_MASK ;
// Two Stop Bits
PDIDATA_LINE_PORT | = PDIDATA_LINE_MASK ;
/* Tristate DATA and CLOCK lines */
BITBANG_PDIDATA_PORT & = ~ BITBANG_PDIDATA_MASK ;
BITBANG_PDICLOCK_PORT & = ~ BITBANG_PDICLOCK_MASK ;
TOGGLE_PDI_CLOCK ;
TOGGLE_PDI_CLOCK ;
TCCR0B = 0 ;
}
void PDITarget_SendByte ( uint8_t Byte )
{
bool IsOddBitsSet = false ;
/* Compute Even parity bit */
for ( uint8_t i = 0 ; i < 8 ; i + + )
{
if ( Byte & ( 1 < < i ) )
IsOddBitsSet = ! ( IsOddBitsSet ) ;
}
/* Data shifted out LSB first, START DATA PARITY STOP STOP */
DataBits = ( ( uint16_t ) IsOddBitsSet < < 10 ) | ( ( uint16_t ) Byte < < 1 ) | ( 1 < < 0 ) ;
BITBANG_PDIDATA_PORT | = BITBANG_PDIDATA_MASK ;
BITBANG_PDIDATA_DDR | = BITBANG_PDIDATA_MASK ;
IsSending = true ;
BitCount = BITS_IN_FRAME ;
while ( BitCount ) ;
BITBANG_PDIDATA_PORT & = ~ BITBANG_PDIDATA_MASK ;
BITBANG_PDIDATA_DDR & = ~ BITBANG_PDIDATA_MASK ;
}
/** Reads a given byte from the attached XMEGA device, encoded in a RS232 frame through the PDI interface.
*
* \ return Received byte from the attached device
*/
uint8_t PDITarget_ReceiveByte ( void )
{
uint8_t ReceivedByte = 0 ;
IsSending = false ;
BitCount = BITS_IN_FRAME ;
while ( BitCount ) ;
PDIDATA_LINE_DDR & = ~ PDIDATA_LINE_MASK ;
return ( DataBits > > 1 ) ;
}
// One Start Bit
while ( PDIDATA_LINE_PIN & PDIDATA_LINE_MASK ) ;
TOGGLE_PDI_CLOCK ;
void PDITarget_SendBreak ( void )
{
DataBits = 0 ;
TOGGLE_PDI_CLOCK ;
BITBANG_PDIDATA_PORT | = BITBANG_PDIDATA_MASK ;
BITBANG_PDIDATA_DDR | = BITBANG_PDIDATA_MASK ;
// Eight Data Bits
for ( uint8_t i = 0 ; i < 8 ; i + + )
{
if ( ! ( PDIDATA_LINE_PIN & PDIDATA_LINE_MASK ) )
ReceivedByte | = 0x80 ;
IsSending = true ;
BitCount = BITS_IN_FRAME ;
while ( BitCount ) ;
ReceivedByte > > = 1 ;
BITBANG_PDIDATA_PORT & = ~ BITBANG_PDIDATA_MASK ;
BITBANG_PDIDATA_DDR & = ~ BITBANG_PDIDATA_MASK ;
}
# else
void PDITarget_EnableTargetPDI ( void )
{
/* Set Tx and XCK as outputs, Rx as input */
DDRD | = ( 1 < < 5 ) | ( 1 < < 3 ) ;
DDRD & = ~ ( 1 < < 2 ) ;
/* Set DATA line high for 90ns to disable /RESET functionality */
PORTD | = ( 1 < < 3 ) ;
asm volatile ( " NOP " : : ) ;
asm volatile ( " NOP " : : ) ;
/* Set up the synchronous USART for XMEGA communications -
8 data bits , even parity , 2 stop bits */
UBRR1 = 10 ;
UCSR1B = ( 1 < < TXEN1 ) ;
UCSR1C = ( 1 < < UMSEL10 ) | ( 1 < < UPM11 ) | ( 1 < < USBS1 ) | ( 1 < < UCSZ11 ) | ( 1 < < UCSZ10 ) | ( 1 < < UCPOL1 ) ;
PDITarget_SendBreak ( ) ;
PDITarget_SendBreak ( ) ;
}
TOGGLE_PDI_CLOCK ;
}
void PDITarget_DisableTargetPDI ( void )
{
/* Turn of receiver and transmitter of the USART, clear settings */
UCSR1B = 0 ;
UCSR1C = 0 ;
// Even Parity Bit (discarded)
TOGGLE_PDI_CLOCK ;
/* Set all USART lines as input, tristate */
DDRD & = ~ ( 1 < < 5 ) | ( 1 < < 3 ) ;
PORTD & = ~ ( ( 1 < < 5 ) | ( 1 < < 3 ) | ( 1 < < 2 ) ) ;
}
// Two Stop Bits
TOGGLE_PDI_CLOCK ;
TOGGLE_PDI_CLOCK ;
void PDITarget_SendByte ( uint8_t Byte )
{
UCSR1B & = ~ ( 1 < < RXEN1 ) ;
UCSR1B | = ( 1 < < TXEN1 ) ;
PDIDATA_LINE_DDR | = PDIDATA_LINE_MASK ;
UDR1 = Byte ;
return ReceivedByte ;
while ( ! ( UCSR1A & ( 1 < < TXC1 ) ) ) ;
UCSR1A | = ( 1 < < TXC1 ) ;
}
uint8_t PDITarget_ReceiveByte ( void )
{
UCSR1B & = ~ ( 1 < < TXEN1 ) ;
UCSR1B | = ( 1 < < RXEN1 ) ;
while ( ! ( UCSR1A & ( 1 < < RXC1 ) ) ) ;
UCSR1A | = ( 1 < < RXC1 ) ;
return UDR1 ;
}
void PDITarget_SendBreak ( void )
{
UCSR1B & = ~ ( 1 < < RXEN1 ) ;
UCSR1B | = ( 1 < < TXEN1 ) ;
for ( uint8_t i = 0 ; i < BITS_IN_FRAME ; i + + )
{
while ( PIND & ( 1 < < 5 ) ) ;
while ( ! ( PIND & ( 1 < < 5 ) ) ) ;
}
}
# endif
# endif
Dean Camera
15 years ago