Merged r9433:9527 from features/gr-usrp2 into trunk. Adds usrp2 and gr-usrp2 top-level components. Trunk passes distcheck with mb-gcc installed, but currently not without them. The key issue is that when mb-gcc is not installed, the build system skips over the usrp2/firmware directory, and the firmware include files don't get put into the dist tarball. But we can't do the usual DIST_SUBDIRS method as the firmware is a subpackage.

git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@9528 221aa14e-8319-0410-a670-987f0aec2ac5

1 files changed, 193 insertions, 0 deletions

diff --git a/opencores/simple_gpio/rtl/simple_gpio.v b/opencores/simple_gpio/rtl/simple_gpio.v
new file mode 100644
index 000000000..0b78f9921
--- /dev/null
+++ b/opencores/simple_gpio/rtl/simple_gpio.v
@@ -0,0 +1,193 @@
+/////////////////////////////////////////////////////////////////////
+////                                                             ////
+////  OpenCores Simple General Purpose IO core                   ////
+////                                                             ////
+////  Author: Richard Herveille                                  ////
+////          richard@asics.ws                                   ////
+////          www.asics.ws                                       ////
+////                                                             ////
+/////////////////////////////////////////////////////////////////////
+////                                                             ////
+//// Copyright (C) 2002 Richard Herveille                        ////
+////                    richard@asics.ws                         ////
+////                                                             ////
+//// This source file may be used and distributed without        ////
+//// restriction provided that this copyright statement is not   ////
+//// removed from the file and that any derivative work contains ////
+//// the original copyright notice and the associated disclaimer.////
+////                                                             ////
+////     THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY     ////
+//// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED   ////
+//// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS   ////
+//// FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR      ////
+//// OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,         ////
+//// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES    ////
+//// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE   ////
+//// GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR        ////
+//// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF  ////
+//// LIABILITY, WHETHER IN  CONTRACT, STRICT LIABILITY, OR TORT  ////
+//// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT  ////
+//// OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE         ////
+//// POSSIBILITY OF SUCH DAMAGE.                                 ////
+////                                                             ////
+/////////////////////////////////////////////////////////////////////
+
+//  CVS Log
+//
+//  $Id: simple_gpio.v,v 1.2 2002/12/22 16:10:17 rherveille Exp $
+//
+//  $Date: 2002/12/22 16:10:17 $
+//  $Revision: 1.2 $
+//  $Author: rherveille $
+//  $Locker:  $
+//  $State: Exp $
+//
+// Change History:
+//               $Log: simple_gpio.v,v $
+//               Revision 1.2  2002/12/22 16:10:17  rherveille
+//               Fixed some typos in the documentation section.
+//
+//
+
+
+
+//
+// Very basic 8bit GPIO core
+//
+//
+// Registers:
+//
+// 0x00: Control Register   <io[7:0]>
+//       bits 7:0 R/W Input/Output    '1' = output mode
+//                                    '0' = input mode
+// 0x01: Line Register
+//       bits 7:0 R   Status                Current GPIO pin level
+//                W   Output                GPIO pin output level
+//
+//
+// HOWTO:
+//
+// Use a pin as an input:
+// Program the corresponding bit in the control register to 'input mode' ('0').
+// The pin's state (input level) can be checked by reading the Line Register.
+// Writing to the GPIO pin's Line Register bit while in input mode has no effect.
+//
+// Use a pin as an output:
+// Program the corresponding bit in the control register to 'output mode' ('1').
+// Program the GPIO pin's output level by writing to the corresponding bit in
+// the Line Register.
+// Reading the GPIO pin's Line Register bit while in output mode returns the
+// current output level.
+//
+// Addapt the core for fewer GPIOs:
+// If less than 8 GPIOs are required, than the 'io' parameter can be set to
+// the amount of required interrupts. GPIOs are mapped starting at the LSBs.
+// So only the 'io' LSBs per register are valid.
+// All other bits (i.e. the 8-'io' MSBs) are set to zero '0'.
+// Codesize is approximately linear to the amount of interrupts. I.e. using
+// 4 instead of 8 GPIO sources reduces the size by approx. half.
+//
+
+
+// synopsys translate_off
+`include "timescale.v"
+// synopsys translate_on
+
+module simple_gpio(
+  clk_i, rst_i, cyc_i, stb_i, adr_i, we_i, dat_i, dat_o, ack_o,
+  gpio
+);
+
+  //
+  // Inputs & outputs
+  //
+  parameter io = 8;            // number of GPIOs
+
+  // 8bit WISHBONE bus slave interface
+  input         clk_i;         // clock
+  input         rst_i;         // reset (asynchronous active low)
+  input         cyc_i;         // cycle
+  input         stb_i;         // strobe
+  input         adr_i;         // address adr_i[1]
+  input         we_i;          // write enable
+  input  [ 7:0] dat_i;         // data output
+  output [ 7:0] dat_o;         // data input
+  output        ack_o;         // normal bus termination
+
+  // GPIO pins
+  inout  [io:1] gpio;
+
+  //
+  // Module body
+  //
+  reg [io:1] ctrl, line;                  // ControlRegister, LineRegister
+  reg [io:1] lgpio, llgpio;               // LatchedGPIO pins
+
+  //
+  // perform parameter checks
+  //
+  // synopsys translate_off
+  initial
+  begin
+      if(io > 8)
+        $display("simple_gpio: max. 8 GPIOs supported.");
+  end
+  // synopsys translate_on
+
+  //
+  // WISHBONE interface
+
+  wire wb_acc = cyc_i & stb_i;            // WISHBONE access
+  wire wb_wr  = wb_acc & we_i;            // WISHBONE write access
+
+  always @(posedge clk_i or negedge rst_i)
+    if (~rst_i)
+      begin
+          ctrl <= #1 {io{1'b0}};
+          line <= #1 {io{1'b0}};
+      end
+    else if (wb_wr)
+       if ( adr_i )
+         line <= #1 dat_i[io-1:0];
+       else
+         ctrl <= #1 dat_i[io-1:0];
+
+
+  reg [7:0] dat_o;
+  always @(posedge clk_i)
+    if ( adr_i )
+      dat_o <= #1 { {(8-io){1'b0}}, llgpio};
+    else
+      dat_o <= #1 { {(8-io){1'b0}}, ctrl};
+
+  reg ack_o;
+  always @(posedge clk_i or negedge rst_i)
+    if (~rst_i)
+      ack_o <= #1 1'b0;
+    else
+      ack_o <= #1 wb_acc & !ack_o;
+
+
+  //
+  // GPIO section
+
+  // latch GPIO input pins
+  always @(posedge clk_i)
+    lgpio <= #1 gpio;
+
+  // latch again (reduce meta-stability risc)
+  always @(posedge clk_i)
+    llgpio <= #1 lgpio;
+
+  // assign GPIO outputs
+  integer n;
+  reg [io:1] igpio; // temporary internal signal
+
+  always @(ctrl or line)
+    for(n=1;n<=io;n=n+1)
+      igpio[n] <= ctrl[n] ? line[n] : 1'bz;
+
+  assign gpio = igpio;
+
+endmodule
+