LISP processor works now

[clump.git] / gc.v

diff --git a/gc.v b/gc.v
index 64eb8fa6b8c1a12955874c6b6d63b80792c1ac78..682f51a89134bde756dcd3ec1cf1d50d643c903e 100644 (file)
--- a/gc.v
+++ b/gc.v
@@ -1,8 +1,10 @@
-module GC (input clk, input mclk, input [7:0] Ein, output [7:0] Eout, input [3:0] gcop, output [5:0] ostate, output step_eval);
-   reg [5:0] gostate = 6'o2;
-   reg [5:0] gnstate;
+`include "gcram.v"
+
+module GC (input clk, input mclk, input [7:0] Ein, output [7:0] Eout, input [3:0] gcop, output [5:0] ostate, output conn_et, output conn_ea, output step_eval, output [7:0] result);
    reg [15:0] rom_output;
-   reg [7:0]  Ein_latched;
+   reg [5:0]  gostate = 6'o0;
+   reg [5:0]  gnstate;
+   reg [7:0]  Ein_latched = 6'h44; // initial value of E
 
    always @(posedge clk) begin
          Ein_latched <= Ein;
@@ -21,8 +23,8 @@ module GC (input clk, input mclk, input [7:0] Ein, output [7:0] Eout, input [3:0
    wire ldQ          = rom_output[5];
    wire ldP          = rom_output[4];
    wire conn_i       = rom_output[3];
-   wire conn_et      = rom_output[2];
-   wire conn_ea      = rom_output[1];
+   assign conn_et    = rom_output[2];
+   assign conn_ea    = rom_output[1];
    assign step_eval  = rom_output[0];
 
    wire ga_zero = ~|G[7:5];
@@ -39,7 +41,7 @@ module GC (input clk, input mclk, input [7:0] Ein, output [7:0] Eout, input [3:0
                6'o07:   begin rom_output <= 16'o002020; gnstate <= 6'o10; end
                6'o10:   begin rom_output <= 16'o001200; gnstate <= 6'o11; end
                6'o11:   begin rom_output <= 16'o004020; gnstate <= 6'o12; end
-               6'o12:   begin rom_output <= 16'o002100; gnstate <= 6'o13; end
+               6'o12:   begin rom_output <= 16'o002100 | (1 << 12); gnstate <= 6'o13; end
                6'o13:   begin rom_output <= 16'o000057; gnstate <= 6'o02; end
                6'o14:   begin rom_output <= 16'o004020; gnstate <= 6'o04; end
                6'o15:   begin rom_output <= 16'o000246; gnstate <= 6'o16; end
@@ -79,18 +81,18 @@ module GC (input clk, input mclk, input [7:0] Ein, output [7:0] Eout, input [3:0
                6'o57:   begin rom_output <= 16'o004007; gnstate <= 6'o02; end
                default: begin rom_output <= 16'o040000; gnstate <= 6'o20; end
          endcase; // case (gostate)
-   end // always @ (posedge mclk)
+   end // always @ *
 
    always @ (posedge clk) begin
          gostate <=
-                          /*                           ga_zero_disp ? (gnstate | ga_zero) : */
+                               ga_zero_disp ? (gnstate | ga_zero) :
                                gcop_disp ? (gnstate | gcop) :
                                gnstate;
    end // always @ (posedge clk)
 
    assign ostate = gostate;
 
-   reg [4:0] P = 5'b0; // free storage pointer begins at 0
+   reg [4:0] P;
    reg [7:0] Q;
    reg [7:0] R;
    reg [7:0] S;
@@ -100,6 +102,7 @@ module GC (input clk, input mclk, input [7:0] Ein, output [7:0] Eout, input [3:0
    wire [7:0] I;
 
    wire [7:0] G;
+   wire [7:0] Gout;
 
    /*
    assign G = rdR ? R : 8'bzzzzzzzz;
@@ -124,24 +127,12 @@ module GC (input clk, input mclk, input [7:0] Ein, output [7:0] Eout, input [3:0
    wire [7:0] GfromE = {GTfromE, GAfromE};
 
    assign G = GfromR | GfromQ | GfromP | GfromP_plus | GfromI | GfromE;
+   assign Gout = GfromR | GfromQ | GfromP | GfromP_plus | GfromI;
+
+   assign Eout[4:0] = conn_ea ? Gout[4:0] : 0;
+   assign Eout[7:5] = conn_et ? Gout[7:5] : 0;
 
-   assign Eout[4:0] = conn_ea ? G[4:0] : 0;
-   assign Eout[7:5] = conn_et ? G[7:5] : 0;
-
-   generic_dpram #(.aw(5), .dw(8)) RAM
-        ( .rclk(mclk),
-          .wclk(mclk),
-          .rrst(1'b0),
-          .wrst(1'b0),
-          .rce(1'b1),
-          .wce(1'b1),
-
-          .oe(1'b1),
-          .we(write),
-          .raddr(A),
-          .waddr(A),
-          .do(I),
-          .di(S));
+   GCRAM gcram (.clk(mclk), .we(write), .addr(A), .do(I), .di(S), .result(result));
 
    always @ (posedge clk) begin
          if (ldS) S = G;