From 3ef57bf3bfeca4051c46231d143646a687322bb5 Mon Sep 17 00:00:00 2001
From: "rmackay9@yahoo.com"
 <rmackay9@yahoo.com@f9c3cf11-9bcb-44bc-f272-b75c42450872>
Date: Sat, 30 Apr 2011 03:25:31 +0000
Subject: [PATCH] DataFlash - modified to use Arduino SPI interface instead of
 directly using registers.  Also moved "dataflash_CS_inactive" calls to end of
 functions instead of beginning so that it doesn't monopolize the SPI bus.

git-svn-id: https://arducopter.googlecode.com/svn/trunk@1931 f9c3cf11-9bcb-44bc-f272-b75c42450872
---
 libraries/DataFlash/DataFlash.cpp | 162 +++++++++++++++---------------
 1 file changed, 83 insertions(+), 79 deletions(-)

diff --git a/libraries/DataFlash/DataFlash.cpp b/libraries/DataFlash/DataFlash.cpp
index 10c798e906..0b770a919b 100644
--- a/libraries/DataFlash/DataFlash.cpp
+++ b/libraries/DataFlash/DataFlash.cpp
@@ -39,16 +39,11 @@ extern "C" {
 }
 
 #include "DataFlash.h"
+#include "../SPI/SPI.h"
 
 #define OVERWRITE_DATA 0 // 0: When reach the end page stop, 1: Start overwritten from page 1
 
 // *** INTERNAL FUNCTIONS ***
-unsigned char dataflash_SPI_transfer(unsigned char output)
-{
-  SPDR = output;                     // Start the transmission
-  while (!(SPSR & (1<<SPIF)));       // Wait the end of the transmission
-  return SPDR; 
-}
 
 void dataflash_CS_inactive()
 {
@@ -87,13 +82,10 @@ void DataFlash_Class::Init(void)
   dataflash_CS_inactive();     //disable device
   
   // Setup SPI  Master, Mode 3, fosc/4 = 4MHz
-  SPCR = (1<<SPE)|(1<<MSTR)|(1<<CPHA)|(1<<CPOL);
-  // Setup SPI  Master, Mode 3, 2MHz
-  //SPCR = (1<<SPE)|(1<<MSTR)|(1<<CPHA)|(1<<CPOL)|(1<<SPR0);
-  //SPSR = (1<<SPI2X);
-  // Cleanup registers...
-  tmp=SPSR;
-  tmp=SPDR;
+  SPI.begin();
+  SPI.setBitOrder(MSBFIRST);
+  SPI.setDataMode(SPI_MODE3);
+  SPI.setClockDivider(SPI_CLOCK_DIV4);
 
   // get page size: 512 or 528
   df_PageSize=PageSize();
@@ -103,28 +95,30 @@ void DataFlash_Class::Init(void)
 void DataFlash_Class::ReadManufacturerID()
 {
   byte tmp;
-  
-  dataflash_CS_inactive();    // Reset dataflash command decoder
-  dataflash_CS_active();     
+
+  dataflash_CS_active();     // activate dataflash
  
   // Read manufacturer and ID command...
-  dataflash_SPI_transfer(DF_READ_MANUFACTURER_AND_DEVICE_ID);
+  SPI.transfer(DF_READ_MANUFACTURER_AND_DEVICE_ID);
 
-  df_manufacturer = dataflash_SPI_transfer(0xff);
-  df_device_0 = dataflash_SPI_transfer(0xff);
-  df_device_1 = dataflash_SPI_transfer(0xff);
-  tmp = dataflash_SPI_transfer(0xff);
+  df_manufacturer = SPI.transfer(0xff);
+  df_device_0 = SPI.transfer(0xff);
+  df_device_1 = SPI.transfer(0xff);
+  tmp = SPI.transfer(0xff);
+
+  dataflash_CS_inactive();    // Reset dataflash command decoder  
 }
 
 // Read the status register
 byte DataFlash_Class::ReadStatusReg()
 { 
-  dataflash_CS_inactive();    // Reset dataflash command decoder
-  dataflash_CS_active();     
+  dataflash_CS_active();     // activate dataflash
  
-  // Read status command
-  dataflash_SPI_transfer(DF_STATUS_REGISTER_READ);
-  return dataflash_SPI_transfer(0x00);  // We only want to extract the READY/BUSY bit
+  // Read status command  
+  SPI.transfer(DF_STATUS_REGISTER_READ);
+  return SPI.transfer(0x00);  // We only want to extract the READY/BUSY bit
+  
+  dataflash_CS_inactive();    // Reset dataflash command decoder  
 }
 
 // Read the status of the DataFlash
@@ -150,46 +144,48 @@ void DataFlash_Class::WaitReady()
 
 void DataFlash_Class::PageToBuffer(unsigned char BufferNum, unsigned int PageAdr)
 {
-  dataflash_CS_inactive();	
   dataflash_CS_active();		
-  if (BufferNum==1)				
-    dataflash_SPI_transfer(DF_TRANSFER_PAGE_TO_BUFFER_1);
-  else
-    dataflash_SPI_transfer(DF_TRANSFER_PAGE_TO_BUFFER_2);
+  if (BufferNum==1)	{
+	SPI.transfer(DF_TRANSFER_PAGE_TO_BUFFER_1);
+  }else{
+	SPI.transfer(DF_TRANSFER_PAGE_TO_BUFFER_2);
+  }
   
   if(df_PageSize==512){
-    dataflash_SPI_transfer((unsigned char)(PageAdr >> 7));	
-    dataflash_SPI_transfer((unsigned char)(PageAdr << 1));	
+	SPI.transfer((unsigned char)(PageAdr >> 7));
+	SPI.transfer((unsigned char)(PageAdr << 1));
   }else{
-    dataflash_SPI_transfer((unsigned char)(PageAdr >> 6));	
-    dataflash_SPI_transfer((unsigned char)(PageAdr << 2));
+	SPI.transfer((unsigned char)(PageAdr >> 6));
+	SPI.transfer((unsigned char)(PageAdr << 2));
   }
-  dataflash_SPI_transfer(0x00);	// don´t care bytes			
+  SPI.transfer(0x00);	// don´t care bytes	
 
   dataflash_CS_inactive();	//initiate the transfer
   dataflash_CS_active();
   
   while(!ReadStatus());  //monitor the status register, wait until busy-flag is high
+  
+  dataflash_CS_inactive();  
 }
 
 void DataFlash_Class::BufferToPage (unsigned char BufferNum, unsigned int PageAdr, unsigned char wait)
 {
-  dataflash_CS_inactive();     // Reset dataflash command decoder
   dataflash_CS_active();
   
-  if (BufferNum==1)	
-    dataflash_SPI_transfer(DF_BUFFER_1_TO_PAGE_WITH_ERASE);
-  else
-    dataflash_SPI_transfer(DF_BUFFER_2_TO_PAGE_WITH_ERASE);
-
-  if(df_PageSize==512){
-    dataflash_SPI_transfer((unsigned char)(PageAdr >> 7));	
-    dataflash_SPI_transfer((unsigned char)(PageAdr << 1));	
+  if (BufferNum==1)	{
+	SPI.transfer(DF_BUFFER_1_TO_PAGE_WITH_ERASE);
   }else{
-    dataflash_SPI_transfer((unsigned char)(PageAdr >> 6));	
-    dataflash_SPI_transfer((unsigned char)(PageAdr << 2));
+	SPI.transfer(DF_BUFFER_2_TO_PAGE_WITH_ERASE);
   }
-  dataflash_SPI_transfer(0x00);	// don´t care bytes			
+  
+  if(df_PageSize==512){
+    SPI.transfer((unsigned char)(PageAdr >> 7));
+    SPI.transfer((unsigned char)(PageAdr << 1));
+  }else{
+	SPI.transfer((unsigned char)(PageAdr >> 6));
+	SPI.transfer((unsigned char)(PageAdr << 2));
+  }		
+  SPI.transfer(0x00);	// don´t care bytes
 
   dataflash_CS_inactive();	//initiate the transfer
   dataflash_CS_active();
@@ -197,39 +193,45 @@ void DataFlash_Class::BufferToPage (unsigned char BufferNum, unsigned int PageAd
   // Check if we need to wait to write the buffer to memory or we can continue...
   if (wait)
 	while(!ReadStatus());  //monitor the status register, wait until busy-flag is high
+	
+  dataflash_CS_inactive();     // Reset dataflash command decoder	
 }
 
 void DataFlash_Class::BufferWrite (unsigned char BufferNum, unsigned int IntPageAdr, unsigned char Data)
 {
-  dataflash_CS_inactive();   // Reset dataflash command decoder
   dataflash_CS_active();
   
-  if (BufferNum==1)	
-    dataflash_SPI_transfer(DF_BUFFER_1_WRITE);
-  else
-    dataflash_SPI_transfer(DF_BUFFER_2_WRITE);
-  dataflash_SPI_transfer(0x00);				 //don't cares
-  dataflash_SPI_transfer((unsigned char)(IntPageAdr>>8));  //upper part of internal buffer address
-  dataflash_SPI_transfer((unsigned char)(IntPageAdr));	 //lower part of internal buffer address
-  dataflash_SPI_transfer(Data);				 //write data byte
+  if (BufferNum==1)	{
+	SPI.transfer(DF_BUFFER_1_WRITE);
+  }else{
+	SPI.transfer(DF_BUFFER_2_WRITE);
+  }
+  SPI.transfer(0x00);				 //don't cares
+  SPI.transfer((unsigned char)(IntPageAdr>>8));  //upper part of internal buffer address
+  SPI.transfer((unsigned char)(IntPageAdr));	 //lower part of internal buffer address
+  SPI.transfer(Data);				 //write data byte
+  
+  dataflash_CS_inactive();   // Reset dataflash command decoder  
 }
   
 unsigned char DataFlash_Class::BufferRead (unsigned char BufferNum, unsigned int IntPageAdr)
 {
   byte tmp;
   
-  dataflash_CS_inactive();   // Reset dataflash command decoder
   dataflash_CS_active();
   
-  if (BufferNum==1)	
-    dataflash_SPI_transfer(DF_BUFFER_1_READ);
-  else
-    dataflash_SPI_transfer(DF_BUFFER_2_READ);
-  dataflash_SPI_transfer(0x00);				 //don't cares
-  dataflash_SPI_transfer((unsigned char)(IntPageAdr>>8));  //upper part of internal buffer address
-  dataflash_SPI_transfer((unsigned char)(IntPageAdr));	 //lower part of internal buffer address
-  dataflash_SPI_transfer(0x00);                            //don't cares
-  tmp = dataflash_SPI_transfer(0x00);		         //read data byte
+  if (BufferNum==1)	{
+	SPI.transfer(DF_BUFFER_1_READ);
+  }else{
+	SPI.transfer(DF_BUFFER_2_READ);
+  }
+  SPI.transfer(0x00);				 //don't cares
+  SPI.transfer((unsigned char)(IntPageAdr>>8));  //upper part of internal buffer address
+  SPI.transfer((unsigned char)(IntPageAdr));	 //lower part of internal buffer address
+  SPI.transfer(0x00);                            //don't cares
+  tmp = SPI.transfer(0x00);		         //read data byte
+  
+  dataflash_CS_inactive();   // Reset dataflash command decoder
   
   return (tmp);
 }
@@ -237,38 +239,40 @@ unsigned char DataFlash_Class::BufferRead (unsigned char BufferNum, unsigned int
 
 void DataFlash_Class::PageErase (unsigned int PageAdr)
 {
-  dataflash_CS_inactive();																//make sure to toggle CS signal in order
   dataflash_CS_active();																//to reset Dataflash command decoder
-  dataflash_SPI_transfer(DF_PAGE_ERASE);   // Command
+  SPI.transfer(DF_PAGE_ERASE);   // Command
 
   if(df_PageSize==512){
-    dataflash_SPI_transfer((unsigned char)(PageAdr >> 7));	
-    dataflash_SPI_transfer((unsigned char)(PageAdr << 1));	
+    SPI.transfer((unsigned char)(PageAdr >> 7));	
+    SPI.transfer((unsigned char)(PageAdr << 1));	
   }else{
-    dataflash_SPI_transfer((unsigned char)(PageAdr >> 6));	
-    dataflash_SPI_transfer((unsigned char)(PageAdr << 2));
+    SPI.transfer((unsigned char)(PageAdr >> 6));	
+    SPI.transfer((unsigned char)(PageAdr << 2));
   }
 
-  dataflash_SPI_transfer(0x00);	           // "dont cares"
+  SPI.transfer(0x00);	           // "dont cares"
   dataflash_CS_inactive();               //initiate flash page erase
   dataflash_CS_active();
   while(!ReadStatus());
+  
+  dataflash_CS_inactive();																//make sure to toggle CS signal in order  
 }
 
 
 void DataFlash_Class::ChipErase ()
 {
-  dataflash_CS_inactive();																//make sure to toggle CS signal in order
   dataflash_CS_active();																//to reset Dataflash command decoder
   // opcodes for chip erase
-  dataflash_SPI_transfer(DF_CHIP_ERASE_0);
-  dataflash_SPI_transfer(DF_CHIP_ERASE_1);
-  dataflash_SPI_transfer(DF_CHIP_ERASE_2);
-  dataflash_SPI_transfer(DF_CHIP_ERASE_3);
+  SPI.transfer(DF_CHIP_ERASE_0);
+  SPI.transfer(DF_CHIP_ERASE_1);
+  SPI.transfer(DF_CHIP_ERASE_2);
+  SPI.transfer(DF_CHIP_ERASE_3);
   
   dataflash_CS_inactive();               //initiate flash page erase
   dataflash_CS_active();
   while(!ReadStatus());
+  
+  dataflash_CS_inactive();																//make sure to toggle CS signal in order  
 }
 
 // *** DATAFLASH PUBLIC FUNCTIONS ***