first working version of usb-spi

git-svn-id: https://svn.spreadspace.org/avr/trunk@43 aa12f405-d877-488e-9caf-2d797e2a1cc7

1 files changed, 58 insertions, 72 deletions

diff --git a/usb-spi/usb-spi.c b/usb-spi/usb-spi.c
index a4d578b..db85730 100644
--- a/usb-spi/usb-spi.c
+++ b/usb-spi/usb-spi.c
@@ -72,12 +72,21 @@
 #include "led.h"

 

 #include <LUFA/Version.h>

-#include <LUFA/Drivers/Peripheral/Serial.h>

 #include <LUFA/Drivers/Misc/RingBuffer.h>

 #include <LUFA/Drivers/USB/USB.h>

 

+    /* Hardware Defines: */

+#define SPI_DDR DDRB

+#define SPI_PORT PORTB

+#define SPI_PINB_REG  PINB

+#define CS   0

+#define SCK  1

+#define MOSI 2

+#define MISO 3

+

     /* Function Prototypes: */

 void SetupHardware(void);

+void SPI_TransferBuffer(void);

 

 void EVENT_USB_Device_Connect(void);

 void EVENT_USB_Device_Disconnect(void);

@@ -87,16 +96,16 @@ void EVENT_USB_Device_ControlRequest(void);
 void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo);

 

 /** Circular buffer to hold data from the host before it is sent to the device via the serial port. */

-static RingBuffer_t USBtoUSART_Buffer;

+static RingBuffer_t USBtoSPI_Buffer;

 

-/** Underlying data buffer for \ref USBtoUSART_Buffer, where the stored bytes are located. */

-static uint8_t      USBtoUSART_Buffer_Data[128];

+/** Underlying data buffer for \ref USBtoSPI_Buffer, where the stored bytes are located. */

+static uint8_t      USBtoSPI_Buffer_Data[128];

 

 /** Circular buffer to hold data from the serial port before it is sent to the host. */

-static RingBuffer_t USARTtoUSB_Buffer;

+static RingBuffer_t SPItoUSB_Buffer;

 

-/** Underlying data buffer for \ref USARTtoUSB_Buffer, where the stored bytes are located. */

-static uint8_t      USARTtoUSB_Buffer_Data[128];

+/** Underlying data buffer for \ref SPItoUSB_Buffer, where the stored bytes are located. */

+static uint8_t      SPItoUSB_Buffer_Data[128];

 

 /** LUFA CDC Class driver interface configuration and state information. This structure is

  *  passed to all CDC Class driver functions, so that multiple instances of the same class

@@ -130,48 +139,48 @@ int main(void)
 {

 	SetupHardware();

 

-	RingBuffer_InitBuffer(&USBtoUSART_Buffer, USBtoUSART_Buffer_Data, sizeof(USBtoUSART_Buffer_Data));

-	RingBuffer_InitBuffer(&USARTtoUSB_Buffer, USARTtoUSB_Buffer_Data, sizeof(USARTtoUSB_Buffer_Data));

+	RingBuffer_InitBuffer(&USBtoSPI_Buffer, USBtoSPI_Buffer_Data, sizeof(USBtoSPI_Buffer_Data));

+	RingBuffer_InitBuffer(&SPItoUSB_Buffer, SPItoUSB_Buffer_Data, sizeof(SPItoUSB_Buffer_Data));

 

 	sei();

 

 	for (;;)

 	{

 		/* Only try to read in bytes from the CDC interface if the transmit buffer is not full */

-		if (!(RingBuffer_IsFull(&USBtoUSART_Buffer)))

+		if (!(RingBuffer_IsFull(&USBtoSPI_Buffer)))

 		{

 			int16_t ReceivedByte = CDC_Device_ReceiveByte(&VirtualSerial_CDC_Interface);

 

-			/* Read bytes from the USB OUT endpoint into the USART transmit buffer */

+			/* Read bytes from the USB OUT endpoint into the SPI transmit buffer */

 			if (!(ReceivedByte < 0))

-			  RingBuffer_Insert(&USBtoUSART_Buffer, ReceivedByte);

+			  RingBuffer_Insert(&USBtoSPI_Buffer, ReceivedByte);

 		}

 

-		/* Check if the UART receive buffer flush timer has expired or the buffer is nearly full */

-		uint16_t BufferCount = RingBuffer_GetCount(&USARTtoUSB_Buffer);

-		if ((TIFR0 & (1 << TOV0)) || (BufferCount > (uint8_t)(sizeof(USARTtoUSB_Buffer_Data) * .75)))

+		/* Check if the SPI receive buffer flush timer has expired or the buffer is nearly full */

+		uint16_t BufferCount = RingBuffer_GetCount(&SPItoUSB_Buffer);

+		if ((TIFR0 & (1 << TOV0)) || (BufferCount > (uint8_t)(sizeof(SPItoUSB_Buffer_Data) * .75)))

 		{

 			/* Clear flush timer expiry flag */

 			TIFR0 |= (1 << TOV0);

 

-			/* Read bytes from the USART receive buffer into the USB IN endpoint */

+			/* Read bytes from the SPI receive buffer into the USB IN endpoint */

 			while (BufferCount--)

 			{

 				/* Try to send the next byte of data to the host, abort if there is an error without dequeuing */

 				if (CDC_Device_SendByte(&VirtualSerial_CDC_Interface,

-				                        RingBuffer_Peek(&USARTtoUSB_Buffer)) != ENDPOINT_READYWAIT_NoError)

+				                        RingBuffer_Peek(&SPItoUSB_Buffer)) != ENDPOINT_READYWAIT_NoError)

 				{

 					break;

 				}

 

 				/* Dequeue the already sent byte from the buffer now we have confirmed that no transmission error occurred */

-				RingBuffer_Remove(&USARTtoUSB_Buffer);

+				RingBuffer_Remove(&SPItoUSB_Buffer);

 			}

 		}

 

-		/* Load the next byte from the USART transmit buffer into the USART */

-		if (!(RingBuffer_IsEmpty(&USBtoUSART_Buffer)))

-		  Serial_SendByte(RingBuffer_Remove(&USBtoUSART_Buffer));

+		/* Load the next byte from the SPI transmit buffer into the SPI Interface */

+		if (!(RingBuffer_IsEmpty(&USBtoSPI_Buffer)))

+		  SPI_TransferBuffer();

 

 		CDC_Device_USBTask(&VirtualSerial_CDC_Interface);

 		USB_USBTask();

@@ -191,6 +200,31 @@ void SetupHardware(void)
 

 	/* Start the flush timer so that overflows occur rapidly to push received bytes to the USB interface */

 	TCCR0B = (1 << CS02);

+

+  /* Initialize SPI Interfaces 

+     configure Direction of SS / PB0 , MOSI and SCLK as Output */

+  SPI_DDR = (1<<MOSI)|(1<<SCK)|(1<<CS);

+  SPI_PORT = (1<<CS);

+  SPCR = (1<<SPE)|(1<<MSTR);

+}

+

+void SPI_TransferBuffer()

+{

+  SPI_PORT &= ~(1<<CS);

+

+  while(!(RingBuffer_IsEmpty(&USBtoSPI_Buffer))) {

+    SPDR = RingBuffer_Remove(&USBtoSPI_Buffer);

+    while(!(SPSR & (1<<SPIF)));

+    

+    uint8_t ReceivedByte = SPDR;

+    if (USB_DeviceState == DEVICE_STATE_Configured) {

+      RingBuffer_Insert(&SPItoUSB_Buffer, ReceivedByte);

+      if(RingBuffer_IsFull(&USBtoSPI_Buffer))

+        break;

+    }

+  }

+  

+  SPI_PORT |= (1<<CS);

 }

 

 /** Event handler for the library USB Connection event. */

@@ -223,62 +257,14 @@ void EVENT_USB_Device_ControlRequest(void)
 	CDC_Device_ProcessControlRequest(&VirtualSerial_CDC_Interface);

 }

 

-/** ISR to manage the reception of data from the serial port, placing received bytes into a circular buffer

- *  for later transmission to the host.

- */

-ISR(USART1_RX_vect, ISR_BLOCK)

-{

-	uint8_t ReceivedByte = UDR1;

-

-	if (USB_DeviceState == DEVICE_STATE_Configured)

-	  RingBuffer_Insert(&USARTtoUSB_Buffer, ReceivedByte);

-}

-

 /** Event handler for the CDC Class driver Line Encoding Changed event.

  *

  *  \param[in] CDCInterfaceInfo  Pointer to the CDC class interface configuration structure being referenced

  */

 void EVENT_CDC_Device_LineEncodingChanged(USB_ClassInfo_CDC_Device_t* const CDCInterfaceInfo)

 {

-	uint8_t ConfigMask = 0;

-

-	switch (CDCInterfaceInfo->State.LineEncoding.ParityType)

-	{

-		case CDC_PARITY_Odd:

-			ConfigMask = ((1 << UPM11) | (1 << UPM10));

-			break;

-		case CDC_PARITY_Even:

-			ConfigMask = (1 << UPM11);

-			break;

-	}

-

-	if (CDCInterfaceInfo->State.LineEncoding.CharFormat == CDC_LINEENCODING_TwoStopBits)

-	  ConfigMask |= (1 << USBS1);

-

-	switch (CDCInterfaceInfo->State.LineEncoding.DataBits)

-	{

-		case 6:

-			ConfigMask |= (1 << UCSZ10);

-			break;

-		case 7:

-			ConfigMask |= (1 << UCSZ11);

-			break;

-		case 8:

-			ConfigMask |= ((1 << UCSZ11) | (1 << UCSZ10));

-			break;

-	}

-

-	/* Must turn off USART before reconfiguring it, otherwise incorrect operation may occur */

-	UCSR1B = 0;

-	UCSR1A = 0;

-	UCSR1C = 0;

-

-	/* Set the new baud rate before configuring the USART */

-	UBRR1  = SERIAL_2X_UBBRVAL(CDCInterfaceInfo->State.LineEncoding.BaudRateBPS);

-

-	/* Reconfigure the USART in double speed mode for a wider baud rate range at the expense of accuracy */

-	UCSR1C = ConfigMask;

-	UCSR1A = (1 << U2X1);

-	UCSR1B = ((1 << RXCIE1) | (1 << TXEN1) | (1 << RXEN1));

+/*

+ * Ignore config change for SPI

+ */

 }