Merged features/inband-usb r5224:6306 into trunk. This is work-in-progress on inband signaling for the USRP1.

git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@6307 221aa14e-8319-0410-a670-987f0aec2ac5

1 files changed, 119 insertions, 0 deletions

diff --git a/inband_lib/tx_packer.v b/inband_lib/tx_packer.v
new file mode 100644
index 000000000..2f19b21f3
--- /dev/null
+++ b/inband_lib/tx_packer.v
@@ -0,0 +1,119 @@
+module tx_packer
+   (     //FX2 Side
+			input bus_reset, 
+			input usbclk, 
+			input WR_fx2, 
+			input [15:0]usbdata,
+			
+			// TX Side
+			input reset,
+			input txclk,
+			output reg [31:0] usbdata_final,
+			output reg WR_final);
+
+	reg [8:0] write_count;
+
+	/* Fix FX2 bug */
+	always @(posedge usbclk)
+	begin
+    	if(bus_reset)        // Use bus reset because this is on usbclk
+       		write_count <= #1 0;
+    	else if(WR_fx2 & ~write_count[8])
+    		write_count <= #1 write_count + 9'd1;
+    	else
+    		write_count <= #1 WR_fx2 ? write_count : 9'b0;
+	end
+	
+	reg WR_fx2_fixed;
+	reg [15:0]usbdata_fixed;
+	
+	always @(posedge usbclk) 
+	begin
+	   WR_fx2_fixed <= WR_fx2 & ~write_count[8];
+	   usbdata_fixed <= usbdata;
+	end
+
+	/* Used to convert 16 bits bus_data to the 32 bits wide fifo */
+    reg                             word_complete ;
+    reg     [15:0]         			usbdata_delayed ;
+    reg                             writing ;
+	wire	[31:0]					usbdata_packed ;    
+	wire							WR_packed ;
+   
+    always @(posedge usbclk)
+    begin
+        if (bus_reset)
+          begin
+            word_complete <= 0 ;
+            writing <= 0 ;
+          end
+        else if (WR_fx2_fixed)
+          begin
+            writing <= 1 ;
+            if (word_complete)
+                word_complete <= 0 ;
+            else
+              begin
+                usbdata_delayed <= usbdata_fixed ;
+                word_complete <= 1 ;
+              end
+          end
+        else
+            writing <= 0 ;
+	end
+    
+	assign usbdata_packed = {usbdata_fixed, usbdata_delayed} ;
+    assign WR_packed = word_complete & writing ;
+
+	/* Make sure data are sync with usbclk */
+ 	reg [31:0]usbdata_usbclk;
+	reg WR_usbclk; 
+    
+    always @(posedge usbclk)
+    begin
+    	if (WR_packed)
+    		usbdata_usbclk <= usbdata_packed;
+        WR_usbclk <= WR_packed;
+    end
+
+	/* Cross clock boundaries */
+	reg [31:0] usbdata_tx ;
+	reg WR_tx;
+    reg WR_1;
+    reg WR_2;
+  
+	always @(posedge txclk) usbdata_tx <= usbdata_usbclk;
+
+    always @(posedge txclk) 
+    	if (reset)
+    		WR_1 <= 0;
+    	else
+       		WR_1 <= WR_usbclk;
+
+    always @(posedge txclk) 
+    	if (reset)
+       		WR_2 <= 0;
+    	else
+      		WR_2 <= WR_1;
+
+	always @(posedge txclk)
+	begin
+		if (reset)
+			WR_tx <= 0;
+		else
+		   WR_tx <= WR_1 & ~WR_2;
+	end
+	
+	always @(posedge txclk)
+	begin
+	   if (reset)
+	      WR_final <= 0;
+	   else
+	   begin
+	      WR_final <= WR_tx; 
+	      if (WR_tx)
+	         usbdata_final <= usbdata_tx;
+	   end
+	end
+
+endmodule