Added optional support for Sparkfun SiGe GN3S USB GPS RF sampler:

- Added a pre-compiled custom GN3S firmware.
- Added a fully-compliant GNU Radio source block for GN3S USB dongle. It can be used also from GNU Radio companion and from Python applications.
- Added a new GN3S_Signal_Source block. It is possible to disable the GN3S signal source compilation. See README.

git-svn-id: https://svn.code.sf.net/p/gnss-sdr/code/trunk@217 64b25241-fba3-4117-9849-534c7e92360d

firmware/GN3S_v2/include/gn3s_main.h

@@ -0,0 +1,97 @@
+/* 
+ * Code from: USRP - Universal Software Radio Peripheral (GNU Radio) 
+ * 
+ * Initial modifications by: 
+ * 
+ * Stephan Esterhuizen, Aerospace Engineering Sciences 
+ * University of Colorado at Boulder 
+ * Boulder CO, USA 
+ *  
+ * Further modifications for use with the SiGe USB module to accompany 
+ * the textbook: "A Software-Defined GPS and Galileo Receiver: A 
+ * Single-Frequency Approach" by Kai Borre, Dennis Akos, et.al. by: 
+ * 
+ * Marcus Junered, GNSS Research Group 
+ * Lulea University of Technology 
+ * Lulea, Sweden  
+ *
+ * http://ccar.colorado.edu/gnss 
+ * 
+ * --------------------------------------------------------------------- 
+ * 
+ * GN3S - GNSS IF Streamer for Windows 
+ * Copyright (C) 2006 Marcus Junered 
+ * 
+ * This program is free software; you can redistribute it and/or modify 
+ * it under the terms of the GNU General Public License as published by 
+ * the Free Software Foundation; either version 2 of the License, or 
+ * (at your option) any later version. 
+ * 
+ * This program is distributed in the hope that it will be useful, 
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of 
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
+ * GNU General Public License for more details. 
+ * 
+ * You should have received a copy of the GNU General Public License 
+ * along with this program; if not, write to the Free Software 
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA 
+ */ 
+ 
+ 
+#ifndef _GN3S_MAIN_ 
+#define _GN3S_MAIN_ 
+ 
+#include "usrp_common.h" 
+#include "fx2regs.h" 
+#include "gn3s_regs.h" 
+#include "gpif_inline.h" 
+#include "timer.h" 
+#include "isr.h" 
+#include "usb_common.h" 
+#include "fx2utils.h" 
+#include "gn3s_se4110.h" 
+#include "eeprom.h" 
+#include <string.h> 
+ 
+ 
+// ---------------------------------------------------------------- 
+//          Vendor bmRequestType's 
+// ---------------------------------------------------------------- 
+#define VRT_VENDOR_IN	0xC0 
+#define VRT_VENDOR_OUT	0x40 
+ 
+// IN commands 
+#define VRQ_GET_STATUS  0x80 
+#define GS_TX_UNDERRUN  0   // wIndexL  // returns 1 byte 
+#define GS_RX_OVERRUN   1   // wIndexL  // returns 1 byte 
+ 
+// OUT commands 
+#define VRQ_XFER	0x01  
+#define VRQ_XFER_TX	0x02  
+ 
+#define	bRequestType	SETUPDAT[0] 
+#define	bRequest	SETUPDAT[1] 
+#define	wValueL		SETUPDAT[2] 
+#define	wValueH		SETUPDAT[3] 
+#define	wIndexL		SETUPDAT[4] 
+#define	wIndexH		SETUPDAT[5] 
+#define	wLengthL	SETUPDAT[6] 
+#define	wLengthH	SETUPDAT[7] 
+#define	GUARD       4073
+#undef wordwide
+ 
+// A9 specific 
+#define VRQ_EEPROM  	0xa2 // loads (uploads) EEPROM 
+#define	VRQ_RAM	      	0xa3 // loads (uploads) external ram 
+#define VRQ_DB_FX	0xa9 // Force use of double byte address EEPROM 
+#define EP0BUFF_SIZE	0x40 
+ 
+ 
+// Prototypes 
+static void get_ep0_data(void); 
+unsigned char app_vendor_cmd(void); 
+void guardC(void) interrupt;
+static void main_loop(void); 
+void TD_Init(); 
+ 
+#endif