Forked SPI to NRF.

[goodfet] / firmware / apps / radios / nrf.c

diff --git a/firmware/apps/radios/nrf.c b/firmware/apps/radios/nrf.c
new file mode 100644 (file)
index 0000000..f81afba
--- /dev/null
+++ b/firmware/apps/radios/nrf.c
@@ -0,0 +1,102 @@
+/*! \file nrf.c
+  \author Travis Goodspeed
+  \brief NordicRF Register Interface
+*/
+
+//Higher level left to client application.
+
+#include "platform.h"
+#include "command.h"
+
+#include <signal.h>
+#include <io.h>
+#include <iomacros.h>
+
+#include "nrf.h"
+#include "spi.h"
+
+//This could be more accurate.
+//Does it ever need to be?
+#define NRFSPEED 0
+#define NRFDELAY(x)
+//delay(x)
+
+
+//! Set up the pins for NRF mode.
+void nrfsetup(){
+  P5OUT|=SS;
+  P5DIR|=MOSI+SCK+SS;
+  P5DIR&=~MISO;
+  
+  //Begin a new transaction.
+  P5OUT&=~SS; 
+  P5OUT|=SS;
+}
+
+
+//! Read and write an NRF byte.
+unsigned char nrftrans8(unsigned char byte){
+  register unsigned int bit;
+  //This function came from the NRF Wikipedia article.
+  //Minor alterations.
+  
+  for (bit = 0; bit < 8; bit++) {
+    /* write MOSI on trailing edge of previous clock */
+    if (byte & 0x80)
+      SETMOSI;
+    else
+      CLRMOSI;
+    byte <<= 1;
+ 
+    SETCLK;
+  
+    /* read MISO on trailing edge */
+    byte |= READMISO;
+    CLRCLK;
+  }
+  
+  return byte;
+}
+
+
+
+
+//! Handles a Nordic RF command.
+void nrfhandle(unsigned char app,
+              unsigned char verb,
+              unsigned long len){
+  unsigned long i;
+  
+  //Raise !SS to end transaction, just in case we forgot.
+  P5OUT|=SS;
+  nrfsetup();
+  
+  switch(verb){
+    //PEEK and POKE might come later.
+  case READ:
+  case WRITE:
+    P5OUT&=~SS; //Drop !SS to begin transaction.
+    for(i=0;i<len;i++)
+      cmddata[i]=nrftrans8(cmddata[i]);
+    P5OUT|=SS;  //Raise !SS to end transaction.
+    txdata(app,verb,len);
+    break;
+
+
+
+  case PEEK://Grab NRF Register
+    txdata(app,verb,0);
+    break;
+    
+  case POKE://Poke NRF Register
+    
+    txdata(app,verb,0);
+    break;
+    
+  case SETUP:
+    nrfsetup();
+    txdata(app,verb,0);
+    break;
+  }
+  
+}