X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/258a6a01777afadbf6913246f12a7106b421b795..32b7762325829c6e7a4168bb7db5084a34673f20:/Projects/AVRISP/Lib/PDITarget.c

diff --git a/Projects/AVRISP/Lib/PDITarget.c b/Projects/AVRISP/Lib/PDITarget.c
index 672619968..7fa48e6aa 100644
--- a/Projects/AVRISP/Lib/PDITarget.c
+++ b/Projects/AVRISP/Lib/PDITarget.c
@@ -28,7 +28,7 @@
   this software.
 */
 
-#if defined(ENABLE_PDI_PROTOCOL)
+#if defined(ENABLE_PDI_PROTOCOL) || defined(__DOXYGEN__)
 
 /** \file
  *
@@ -38,64 +38,277 @@
 #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 Byte  Byte to send to the attached device
- */
-void PDITarget_SendByte(uint8_t Byte)
+volatile bool     IsSending;
+
+#if !defined(PDI_VIA_HARDWARE_USART)
+volatile uint16_t SoftUSART_Data;
+volatile uint8_t  SoftUSART_BitCount;
+
+ISR(TIMER0_COMPA_vect, ISR_BLOCK)
 {
-	PDIDATA_LINE_PORT &= ~PDIDATA_LINE_MASK;
+	/* Toggle CLOCK pin in a single cycle (see AVR datasheet) */
+	BITBANG_PDICLOCK_PIN |= BITBANG_PDICLOCK_MASK;
 
-	TOGGLE_PDI_CLOCK;
+	/* If not sending or receiving, just exit */
+	if (!(SoftUSART_BitCount))
+	  return;
 
-	for (uint8_t i = 0; i < 8; i++)
+	/* Check to see if the current clock state is on the rising or falling edge */
+	bool IsRisingEdge = (BITBANG_PDICLOCK_PORT & BITBANG_PDICLOCK_MASK);
+
+	if (IsSending && !IsRisingEdge)
 	{
-		if (Byte & 0x01)
-		  PDIDATA_LINE_PORT |= PDIDATA_LINE_MASK;
+		if (SoftUSART_Data & 0x01)
+		  BITBANG_PDIDATA_PORT |=  BITBANG_PDIDATA_MASK;
 		else
-		  PDIDATA_LINE_PORT &= ~PDIDATA_LINE_MASK;
-		  
-		Byte >>= 1;
+		  BITBANG_PDIDATA_PORT &= ~BITBANG_PDIDATA_MASK;		  
 
-		TOGGLE_PDI_CLOCK;
+		SoftUSART_Data >>= 1;
+		SoftUSART_BitCount--;
 	}
+	else if (!IsSending && IsRisingEdge)
+	{
+		/* Wait for the start bit when receiving */
+		if ((SoftUSART_BitCount == BITS_IN_FRAME) && (BITBANG_PDIDATA_PIN & BITBANG_PDIDATA_MASK))
+		  return;
+	
+		if (BITBANG_PDIDATA_PIN & BITBANG_PDIDATA_MASK)
+		  SoftUSART_Data |= (1 << BITS_IN_FRAME);
 
-	PDIDATA_LINE_PORT |= PDIDATA_LINE_MASK;
+		SoftUSART_Data >>= 1;
+		SoftUSART_BitCount--;
+	}
+}
+#endif
+
+void PDITarget_EnableTargetPDI(void)
+{
+#if defined(PDI_VIA_HARDWARE_USART)
+	/* Set Tx and XCK as outputs, Rx as input */
+	DDRD |=  (1 << 5) | (1 << 3);
+	DDRD &= ~(1 << 2);
+	
+	/* Set DATA line high for at least 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);
 
-	TOGGLE_PDI_CLOCK;
-	TOGGLE_PDI_CLOCK;
+	/* Send two BREAKs of 12 bits each to enable PDI interface (need at least 16 idle bits) */
+	PDITarget_SendBreak();
+	PDITarget_SendBreak();
+#else
+	/* Set DATA and CLOCK lines to outputs */
+	BITBANG_PDIDATA_DDR  |= BITBANG_PDIDATA_MASK;
+	BITBANG_PDICLOCK_DDR |= BITBANG_PDICLOCK_MASK;
+	
+	/* Set DATA line high for at least 90ns to disable /RESET functionality */
+	BITBANG_PDIDATA_PORT |= BITBANG_PDIDATA_MASK;
+	asm volatile ("NOP"::);
+	asm volatile ("NOP"::);
+
+	/* Fire timer compare ISR every 50 cycles to manage the software USART */
+	OCR0A   = 50;
+	TCCR0A  = (1 << WGM01);
+	TCCR0B  = (1 << CS00);
+	TIMSK0  = (1 << OCIE0A);
+	
+	PDITarget_SendBreak();
+	PDITarget_SendBreak();
+#endif
 }
 
-/** 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)
+void PDITarget_DisableTargetPDI(void)
+{
+#if defined(PDI_VIA_HARDWARE_USART)
+	/* Turn off receiver and transmitter of the USART, clear settings */
+	UCSR1A |= (1 << TXC1) | (1 << RXC1);
+	UCSR1B  = 0;
+	UCSR1C  = 0;
+
+	/* Set all USART lines as input, tristate */
+	DDRD  &= ~((1 << 5) | (1 << 3));
+	PORTD &= ~((1 << 5) | (1 << 3) | (1 << 2));
+#else
+	/* Set DATA and CLOCK lines to inputs */
+	BITBANG_PDIDATA_DDR   &= ~BITBANG_PDIDATA_MASK;
+	BITBANG_PDICLOCK_DDR  &= ~BITBANG_PDICLOCK_MASK;
+	
+	/* Tristate DATA and CLOCK lines */
+	BITBANG_PDIDATA_PORT  &= ~BITBANG_PDIDATA_MASK;
+	BITBANG_PDICLOCK_PORT &= ~BITBANG_PDICLOCK_MASK;
+
+	TCCR0B  = 0;
+#endif
+}
+
+void PDITarget_SendByte(uint8_t Byte)
 {
-	uint8_t ReceivedByte = 0;
+#if defined(PDI_VIA_HARDWARE_USART)
+	/* Switch to Tx mode if currently in Rx mode */
+	if (!(IsSending))
+	{
+		PORTD  |=  (1 << 3);
+		DDRD   |=  (1 << 3);
+
+		UCSR1B &= ~(1 << RXEN1);
+		UCSR1B |=  (1 << TXEN1);
+		
+		IsSending = true;
+	}
+	
+	/* Wait until there is space in the hardware Tx buffer before writing */
+	while (!(UCSR1A & (1 << UDRE1)));
+	UDR1 = Byte;
+#else
+	/* Switch to Tx mode if currently in Rx mode */
+	if (!(IsSending))
+	{
+		BITBANG_PDIDATA_PORT |= BITBANG_PDIDATA_MASK;
+		BITBANG_PDIDATA_DDR  |= BITBANG_PDIDATA_MASK;
 
-	PDIDATA_LINE_DDR &= ~PDIDATA_LINE_MASK;
+		IsSending = true;
+	}
+
+	bool    EvenParityBit = false;
+	uint8_t ParityData    = Byte;
 
-	while (PDIDATA_LINE_PIN & PDIDATA_LINE_MASK);
-	  TOGGLE_PDI_CLOCK;
-	  
+	/* Compute Even parity bit */
 	for (uint8_t i = 0; i < 8; i++)
 	{
-		if (PDIDATA_LINE_PIN & PDIDATA_LINE_MASK)
-			ReceivedByte |= 0x01;
+		EvenParityBit ^= ParityData & 0x01;
+		ParityData    >>= 1;
+	}
+
+	while (SoftUSART_BitCount);
+
+	/* Data shifted out LSB first, START DATA PARITY STOP STOP */
+	SoftUSART_Data     = ((uint16_t)EvenParityBit << 9) | ((uint16_t)Byte << 1) | (1 << 10) | (1 << 11);
+	SoftUSART_BitCount = BITS_IN_FRAME;
+#endif
+}
+
+uint8_t PDITarget_ReceiveByte(void)
+{
+#if defined(PDI_VIA_HARDWARE_USART)
+	/* Switch to Rx mode if currently in Tx mode */
+	if (IsSending)
+	{
+		while (!(UCSR1A & (1 << TXC1)));
+		UCSR1A |=  (1 << TXC1);
+
+		UCSR1B &= ~(1 << TXEN1);
+		UCSR1B |=  (1 << RXEN1);
+
+		DDRD   &= ~(1 << 3);
+		PORTD  &= ~(1 << 3);
+		
+		IsSending = false;
+	}
+
+	/* Wait until a byte has been received before reading */
+	while (!(UCSR1A & (1 << RXC1)));
+	return UDR1;
+#else
+	/* Switch to Rx mode if currently in Tx mode */
+	if (IsSending)
+	{
+		while (SoftUSART_BitCount);
 
-		ReceivedByte <<= 1;
+		BITBANG_PDIDATA_DDR  &= ~BITBANG_PDIDATA_MASK;
+		BITBANG_PDIDATA_PORT &= ~BITBANG_PDIDATA_MASK;
 
-		TOGGLE_PDI_CLOCK;	
+		IsSending = false;
 	}
 
-	TOGGLE_PDI_CLOCK;
-	TOGGLE_PDI_CLOCK;
+	/* Wait until a byte has been received before reading */
+	SoftUSART_BitCount = BITS_IN_FRAME;
+	while (SoftUSART_BitCount);
 	
-	PDIDATA_LINE_DDR |= PDIDATA_LINE_MASK;
+	/* Throw away the start, parity and stop bits to leave only the data */
+	return (uint8_t)(SoftUSART_Data >> 1);
+#endif
+}
+
+void PDITarget_SendBreak(void)
+{
+#if defined(PDI_VIA_HARDWARE_USART)
+	/* Switch to Tx mode if currently in Rx mode */
+	if (!(IsSending))
+	{
+		PORTD  |=  (1 << 3);
+		DDRD   |=  (1 << 3);
+
+		UCSR1B &= ~(1 << RXEN1);
+		UCSR1B |=  (1 << TXEN1);
+		
+		IsSending = true;
+	}
+
+	/* Need to do nothing for a full frame to send a BREAK */
+	for (uint8_t i = 0; i <= BITS_IN_FRAME; i++)
+	{
+		/* Wait for a full cycle of the clock */
+		while (PIND & (1 << 5));
+		while (!(PIND & (1 << 5)));
+	}
+#else
+	/* Switch to Tx mode if currently in Rx mode */
+	if (!(IsSending))
+	{
+		BITBANG_PDIDATA_PORT |= BITBANG_PDIDATA_MASK;
+		BITBANG_PDIDATA_DDR  |= BITBANG_PDIDATA_MASK;
+
+		IsSending = true;
+	}
+	
+	while (SoftUSART_BitCount);
+
+	/* Need to do nothing for a full frame to send a BREAK */
+	SoftUSART_Data     = 0x0FFF;
+	SoftUSART_BitCount = BITS_IN_FRAME;
+#endif
+}
+
+void PDITarget_SendAddress(uint32_t Address)
+{
+	PDITarget_SendByte(Address >> 24);
+	PDITarget_SendByte(Address >> 26);
+	PDITarget_SendByte(Address >> 8);
+	PDITarget_SendByte(Address &  0xFF);
+}
+
+bool PDITarget_WaitWhileNVMBusBusy(void)
+{
+	uint8_t AttemptsRemaining = 255;
+
+	/* Poll the STATUS register to check to see if NVM access has been enabled */
+	while (AttemptsRemaining--)
+	{
+		PDITarget_SendByte(PDI_CMD_LDCS | PDI_STATUS_REG);
+		if (PDITarget_ReceiveByte() & PDI_STATUS_NVM)
+		  return true;
+	}
 	
-	return ReceivedByte;
+	return false;
+}
+
+void PDITarget_WaitWhileNVMControllerBusy(void)
+{
+	/* Poll the NVM STATUS register to check to see if NVM controller is busy */
+	for (;;)
+	{
+		PDITarget_SendByte(PDI_CMD_LDS | (PDI_DATSIZE_1BYTE << 2));
+		PDITarget_SendAddress(DATAMEM_BASE | DATAMEM_NVM_STATUS);
+		
+		if (!(PDITarget_ReceiveByte() & (1 << 7)))
+		  return;
+	}
 }
 
 #endif