DUT(device under test)
这个路由器有16个输入和16个输出端口，每个输入输出端口包括3个信号，即连续的数据，帧，和有效信号。这些信号统一采用位向量形式展现。如果要驱动一个独立的端口，比如说驱动端口3，那么对应的信号则是din[3]，fram_n[3],和valid_n[3]。同理，如果我们要采样一个输出端口7，那么我们采样的相对应信号则是dout[7],frame_n[7]和valido_n[7].如下面这幅图所示：
对于这个路由器的描述：
- 单一上升沿时钟
- 输入和输出数据都是连续的，即每个时钟周期出一位数据
- 数据包的长度以可变长度发送
- 数据包可以从任何输入端口路由到任何到输出端口
- 无内部缓冲或者广播
输入数据包的结构：
-
frame_n
下降沿意味着数据包的第一位
上升沿意味着数据包的最后一位 -
din
数据头和负载（我理解为传输的有效数据） -
valid_n
该信号为低表示数据有效，否则认为数据无效。
输出数据包的时序图如下，需要注意的是只有frameo_n和valido_n都是低电平时才认为输出的数据是有效的。
对于复位信号：
当拉低复位信号后，需要注意的是在通过这个路由器发送数据包之前一定要等待15个时钟周期，在这个15个时钟周期内，路由器在执行自刷新的操作。否则将会刷新失败，后续无法正常工作。
下面贴出router.v的代码：
module router(
reset_n, clock, frame_n, valid_n, din, dout, busy_n, valido_n, frameo_n);
input reset_n, clock;
input [15:0] din, frame_n, valid_n;
output [15:0] dout, valido_n, busy_n, frameo_n;
wire reset;
wire [15:0] arb0, arb1, arb2, arb3, arb4, arb5, arb6, arb7;
wire [15:0] di;
wire [15:0] arb8, arb9, arb10, arb11, arb12, arb13, arb14, arb15;
wire [15:0] arb_head, okstep;
tri0 [15:0] doint;
tri1 [15:0] valdoint_n, frameoint_n;
reg [15:0] dout, valido_n, frameo_n;
reg [3:0] arb_head_num;
assign di = din; //将din赋值给di
assign reset = ~reset_n; //将reset_n信号取反后赋值给reset
assign arb_head = 1 << arb_head_num; //将arb_head_num左移一位赋值给arb_head
rtslice rts0(reset,clock,frame_n[0],valid_n[0],di[0],
arb0,arb1,arb_head[0],okstep[0],
doint,busy_n[0],valdoint_n,frameoint_n);
rtslice rts1(reset,clock,frame_n[1],valid_n[1],di[1],
arb1,arb2,arb_head[1],okstep[1],
doint,busy_n[1],valdoint_n,frameoint_n);
rtslice rts2(reset,clock,frame_n[2],valid_n[2],di[2],
arb2,arb3,arb_head[2],okstep[2],
doint,busy_n[2],valdoint_n,frameoint_n);
rtslice rts3(reset,clock,frame_n[3],valid_n[3],di[3],
arb3,arb4,arb_head[3],okstep[3],
doint,busy_n[3],valdoint_n,frameoint_n);
rtslice rts4(reset,clock,frame_n[4],valid_n[4],di[4],
arb4,arb5,arb_head[4],okstep[4],
doint,busy_n[4],valdoint_n,frameoint_n);
rtslice rts5(reset,clock,frame_n[5],valid_n[5],di[5],
arb5,arb6,arb_head[5],okstep[5],
doint,busy_n[5],valdoint_n,frameoint_n);
rtslice rts6(reset,clock,frame_n[6],valid_n[6],di[6],
arb6,arb7,arb_head[6],okstep[6],
doint,busy_n[6],valdoint_n,frameoint_n);
rtslice rts7(reset,clock,frame_n[7],valid_n[7],di[7],
arb7,arb8,arb_head[7],okstep[7],
doint,busy_n[7],valdoint_n,frameoint_n);
rtslice rts8(reset,clock,frame_n[8],valid_n[8],di[8],
arb8,arb9,arb_head[8],okstep[8],
doint,busy_n[8],valdoint_n,frameoint_n);
rtslice rts9(reset,clock,frame_n[9],valid_n[9],di[9],
arb9,arb10,arb_head[9],okstep[9],
doint,busy_n[9],valdoint_n,frameoint_n);
rtslice rts10(reset,clock,frame_n[10],valid_n[10],di[10],
arb10,arb11,arb_head[10],okstep[10],
doint,busy_n[10],valdoint_n,frameoint_n);
rtslice rts11(reset,clock,frame_n[11],valid_n[11],di[11],
arb11,arb12,arb_head[11],okstep[11],
doint,busy_n[11],valdoint_n,frameoint_n);
rtslice rts12(reset,clock,frame_n[12],valid_n[12],di[12],
arb12,arb13,arb_head[12],okstep[12],
doint,busy_n[12],valdoint_n,frameoint_n);
rtslice rts13(reset,clock,frame_n[13],valid_n[13],di[13],
arb13,arb14,arb_head[13],okstep[13],
doint,busy_n[13],valdoint_n,frameoint_n);
rtslice rts14(reset,clock,frame_n[14],valid_n[14],di[14],
arb14,arb15,arb_head[14],okstep[14],
doint,busy_n[14],valdoint_n,frameoint_n);
//rtslicef rts15(reset,clock,frame_n[15],valid_n[15],di[15],
// arb15,arb0,arb_head[15],okstep[15],
// doint,busy_n[15],valdoint_n,frameoint_n);
rtslice rts15(reset,clock,frame_n[15],valid_n[15],di[15],
arb15,arb0,arb_head[15],okstep[15],
doint,busy_n[15],valdoint_n,frameoint_n);
always @(posedge reset)
begin
arb_head_num <= 4'b0;
end
always @(posedge clock)
begin
dout <= doint;
valido_n <= valdoint_n;
frameo_n <= frameoint_n;
if (reset == 1'b0)
begin
if (okstep[arb_head_num] == 1'b1)
arb_head_num <= arb_head_num + 1;
end
end
endmodule //router
//模块rtslice开始
module rtslice(reset,clock,frame_n,valid_n,din,
iarbin,arbout,arbhead,okstep,
dout,busy_n,valido_n,frameo_n);
input reset,clock,frame_n,valid_n,din, arbhead;
output busy_n,okstep;
input [15:0] iarbin;
output [15:0] arbout,dout,valido_n;
inout [15:0] frameo_n;
reg [4:0] addrsf, addrsel;
reg [5:0] addrfsr;
reg din1, busy_n, frame1_n, frame2_n, vald1_n, arbena;
wire [15:0] dout;
wire [15:0] arbin;
wire busy1_n;
wire [4:0] addrsel_g;
reg [3:0] i;
assign arbin = (arbhead == 1'b1) ? 16'hffff : iarbin;
assign addrsel_g = (arbena == 1'b1) ? addrsel : 5'h0;
// always @ ( posedge clock)
// begin
assign dout[0] =
(addrsel_g == 5'h10 && arbin[0] == 1'b1) ? din1 : 1'bZ;
// end
assign dout[1] =
(addrsel_g == 5'h11 && arbin[1] == 1'b1) ? din1 : 1'bZ;
assign dout[2] =
(addrsel_g == 5'h12 && arbin[2] == 1'b1) ? din1 : 1'bZ;
assign dout[3] =
(addrsel_g == 5'h13 && arbin[3] == 1'b1) ? din1 : 1'bZ;
assign dout[4] =
(addrsel_g == 5'h14 && arbin[4] == 1'b1) ? din1 : 1'bZ;
assign dout[5] =
(addrsel_g == 5'h15 && arbin[5] == 1'b1) ? din1 : 1'bZ;
assign dout[6] =
(addrsel_g == 5'h16 && arbin[6] == 1'b1) ? din1 : 1'bZ;
assign dout[7] =
(addrsel_g == 5'h17 && arbin[7] == 1'b1) ? din1 : 1'bZ;
assign dout[8] =
(addrsel_g == 5'h18 && arbin[8] == 1'b1) ? din1 : 1'bZ;
assign dout[9] =
(addrsel_g == 5'h19 && arbin[9] == 1'b1) ? din1 : 1'bZ;
assign dout[10] =
(addrsel_g == 5'h1a && arbin[10] == 1'b1) ? din1 : 1'bZ;
assign dout[11] =
(addrsel_g == 5'h1b && arbin[11] == 1'b1) ? din1 : 1'bZ;
assign dout[12] =
(addrsel_g == 5'h1c && arbin[12] == 1'b1) ? din1 : 1'bZ;
assign dout[13] =
(addrsel_g == 5'h1d && arbin[13] == 1'b1) ? din1 : 1'bZ;
assign dout[14] =
(addrsel_g == 5'h1e && arbin[14] == 1'b1) ? din1 : 1'bZ;
assign dout[15] =
(addrsel_g == 5'h1f && arbin[15] == 1'b1) ? din1 : 1'bZ;
assign frameo_n[0] =
(addrsel_g == 5'h10 && arbin[0] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[1] =
(addrsel_g == 5'h11 && arbin[1] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[2] =
(addrsel_g == 5'h12 && arbin[2] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[3] =
(addrsel_g == 5'h13 && arbin[3] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[4] =
(addrsel_g == 5'h14 && arbin[4] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[5] =
(addrsel_g == 5'h15 && arbin[5] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[6] =
(addrsel_g == 5'h16 && arbin[6] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[7] =
(addrsel_g == 5'h17 && arbin[7] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[8] =
(addrsel_g == 5'h18 && arbin[8] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[9] =
(addrsel_g == 5'h19 && arbin[9] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[10] =
(addrsel_g == 5'h1a && arbin[10] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[11] =
(addrsel_g == 5'h1b && arbin[11] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[12] =
(addrsel_g == 5'h1c && arbin[12] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[13] =
(addrsel_g == 5'h1d && arbin[13] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[14] =
(addrsel_g == 5'h1e && arbin[14] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[15] =
(addrsel_g == 5'h1f && arbin[15] == 1'b1) ? frame1_n : 1'bZ;
assign valido_n[0] =
(addrsel_g == 5'h10 && arbin[0] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[1] =
(addrsel_g == 5'h11 && arbin[1] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[2] =
(addrsel_g == 5'h12 && arbin[2] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[3] =
(addrsel_g == 5'h13 && arbin[3] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[4] =
(addrsel_g == 5'h14 && arbin[4] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[5] =
(addrsel_g == 5'h15 && arbin[5] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[6] =
(addrsel_g == 5'h16 && arbin[6] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[7] =
(addrsel_g == 5'h17 && arbin[7] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[8] =
(addrsel_g == 5'h18 && arbin[8] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[9] =
(addrsel_g == 5'h19 && arbin[9] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[10] =
(addrsel_g == 5'h1a && arbin[10] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[11] =
(addrsel_g == 5'h1b && arbin[11] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[12] =
(addrsel_g == 5'h1c && arbin[12] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[13] =
(addrsel_g == 5'h1d && arbin[13] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[14] =
(addrsel_g == 5'h1e && arbin[14] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[15] =
(addrsel_g == 5'h1f && arbin[15] == 1'b1) ? vald1_n : 1'bZ;
assign arbout[0] =
(addrsel_g != 5'h10 && arbin[0] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[1] =
(addrsel_g != 5'h11 && arbin[1] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[2] =
(addrsel_g != 5'h12 && arbin[2] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[3] =
(addrsel_g != 5'h13 && arbin[3] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[4] =
(addrsel_g != 5'h14 && arbin[4] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[5] =
(addrsel_g != 5'h15 && arbin[5] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[6] =
(addrsel_g != 5'h16 && arbin[6] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[7] =
(addrsel_g != 5'h17 && arbin[7] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[8] =
(addrsel_g != 5'h18 && arbin[8] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[9] =
(addrsel_g != 5'h19 && arbin[9] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[10] =
(addrsel_g != 5'h1a && arbin[10] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[11] =
(addrsel_g != 5'h1b && arbin[11] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[12] =
(addrsel_g != 5'h1c && arbin[12] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[13] =
(addrsel_g != 5'h1d && arbin[13] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[14] =
(addrsel_g != 5'h1e && arbin[14] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[15] =
(addrsel_g != 5'h1f && arbin[15] == 1'b1) ? 1'b1 : 1'b0;
assign busy1_n = (arbout != arbin) ? 1'b1 : ~addrsel[4];
assign okstep = (arbout == arbin) ? 1'b1 : 1'b0;
always @(posedge reset)
begin
if (reset == 1'b1)
begin
addrsel <= 5'b0;
addrfsr <= 6'b0;
arbena <= 1'b0;
end
end
always @(posedge clock)
begin
frame1_n <= frame_n;
frame2_n <= frame1_n;
busy_n <= busy1_n;
din1 <= din;
vald1_n <= valid_n | ~busy_n ;
if (reset == 1'b0)
begin
if (frame2_n != frame1_n && frame1_n == 1'b1)
begin // frame is now inactive
addrsel <= 5'b0; // clear the address register
addrfsr <= 6'b0; // clear the address flag reg.
arbena <= 1'b0;
end
else
begin
if (addrsel[4] == 1'b1 && frameo_n[addrsel[3:0]] == 1'b1)
arbena <= 1'b1;
end
if (frame1_n != frame_n && frame_n == 1'b0)
addrfsr <= 6'b11_1111;
if (addrfsr[5:4] == 2'b10)
addrsel <= {
addrsf[0],addrsf[1],addrsf[2],addrsf[3],addrsf[4]};
if (addrfsr[4] == 1'b1) addrsf <= (addrsf << 1) | {
4'b0, din1 };
if (addrfsr[5] == 1'b1) addrfsr <= addrfsr << 1;
end
end
endmodule //rtslice
module rtslicef(reset,clock,frame_n,valid_n,din,
iarbin,arbout,arbhead,okstep,
dout,busy_n,valido_n,frameo_n);
input reset,clock,frame_n,valid_n,din, arbhead;
output busy_n,okstep;
input [15:0] iarbin;
output [15:0] arbout,dout,valido_n;
inout [15:0] frameo_n;
reg [4:0] addrsf, addrsel;
reg [5:0] addrfsr;
reg din1, busy_n, frame1_n, frame2_n, vald1_n, arbena;
wire [15:0] dout;
wire [15:0] arbin;
wire busy1_n;
wire [4:0] addrsel_g;
assign arbin = (arbhead == 1'b1) ? 16'hffff : iarbin;
assign addrsel_g = (arbena == 1'b1) ? addrsel : 5'h0;
assign dout[0] =
(addrsel_g == 5'h10 && arbin[0] == 1'b1) ? din1 : 1'bZ;
assign dout[1] =
(addrsel_g == 5'h11 && arbin[1] == 1'b1) ? din1 : 1'bZ;
assign dout[2] =
(addrsel_g == 5'h12 && arbin[2] == 1'b1) ? din1 : 1'bZ;
assign dout[3] =
(addrsel_g == 5'h13 && arbin[3] == 1'b1) ? din1 : 1'bZ;
assign dout[4] =
(addrsel_g == 5'h14 && arbin[4] == 1'b1) ? din1 : 1'bZ;
assign dout[5] =
(addrsel_g == 5'h15 && arbin[5] == 1'b1) ? din1 : 1'bZ;
assign dout[6] =
(addrsel_g == 5'h16 && arbin[6] == 1'b1) ? din1 : 1'bZ;
assign dout[7] =
(addrsel_g == 5'h17 && arbin[7] == 1'b1) ? din1 : 1'bZ;
// stuck at x
assign dout[8] =
// (addrsel_g == 5'h18 && arbin[8] == 1'b1) ? din1 : 1'bZ;
(addrsel_g == 5'h18 && arbin[8] == 1'b1) ? 1'bx : 1'bZ;
assign dout[9] =
(addrsel_g == 5'h19 && arbin[9] == 1'b1) ? din1 : 1'bZ;
assign dout[10] =
(addrsel_g == 5'h1a && arbin[10] == 1'b1) ? din1 : 1'bZ;
assign dout[11] =
(addrsel_g == 5'h1b && arbin[11] == 1'b1) ? din1 : 1'bZ;
assign dout[12] =
(addrsel_g == 5'h1c && arbin[12] == 1'b1) ? din1 : 1'bZ;
assign dout[13] =
(addrsel_g == 5'h1d && arbin[13] == 1'b1) ? din1 : 1'bZ;
assign dout[14] =
(addrsel_g == 5'h1e && arbin[14] == 1'b1) ? din1 : 1'bZ;
assign dout[15] =
(addrsel_g == 5'h1f && arbin[15] == 1'b1) ? din1 : 1'bZ;
assign frameo_n[0] =
(addrsel_g == 5'h10 && arbin[0] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[1] =
(addrsel_g == 5'h11 && arbin[1] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[2] =
(addrsel_g == 5'h12 && arbin[2] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[3] =
(addrsel_g == 5'h13 && arbin[3] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[4] =
(addrsel_g == 5'h14 && arbin[4] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[5] =
(addrsel_g == 5'h15 && arbin[5] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[6] =
(addrsel_g == 5'h16 && arbin[6] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[7] =
(addrsel_g == 5'h17 && arbin[7] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[8] =
(addrsel_g == 5'h18 && arbin[8] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[9] =
(addrsel_g == 5'h19 && arbin[9] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[10] =
(addrsel_g == 5'h1a && arbin[10] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[11] =
(addrsel_g == 5'h1b && arbin[11] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[12] =
(addrsel_g == 5'h1c && arbin[12] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[13] =
(addrsel_g == 5'h1d && arbin[13] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[14] =
(addrsel_g == 5'h1e && arbin[14] == 1'b1) ? frame1_n : 1'bZ;
assign frameo_n[15] =
(addrsel_g == 5'h1f && arbin[15] == 1'b1) ? frame1_n : 1'bZ;
assign valido_n[0] =
(addrsel_g == 5'h10 && arbin[0] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[1] =
(addrsel_g == 5'h11 && arbin[1] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[2] =
(addrsel_g == 5'h12 && arbin[2] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[3] =
(addrsel_g == 5'h13 && arbin[3] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[4] =
(addrsel_g == 5'h14 && arbin[4] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[5] =
(addrsel_g == 5'h15 && arbin[5] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[6] =
(addrsel_g == 5'h16 && arbin[6] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[7] =
(addrsel_g == 5'h17 && arbin[7] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[8] =
(addrsel_g == 5'h18 && arbin[8] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[9] =
(addrsel_g == 5'h19 && arbin[9] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[10] =
(addrsel_g == 5'h1a && arbin[10] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[11] =
(addrsel_g == 5'h1b && arbin[11] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[12] =
(addrsel_g == 5'h1c && arbin[12] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[13] =
(addrsel_g == 5'h1d && arbin[13] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[14] =
(addrsel_g == 5'h1e && arbin[14] == 1'b1) ? vald1_n : 1'bZ;
assign valido_n[15] =
(addrsel_g == 5'h1f && arbin[15] == 1'b1) ? vald1_n : 1'bZ;
assign arbout[0] =
(addrsel_g != 5'h10 && arbin[0] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[1] =
(addrsel_g != 5'h11 && arbin[1] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[2] =
(addrsel_g != 5'h12 && arbin[2] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[3] =
(addrsel_g != 5'h13 && arbin[3] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[4] =
(addrsel_g != 5'h14 && arbin[4] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[5] =
(addrsel_g != 5'h15 && arbin[5] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[6] =
(addrsel_g != 5'h16 && arbin[6] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[7] =
(addrsel_g != 5'h17 && arbin[7] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[8] =
(addrsel_g != 5'h18 && arbin[8] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[9] =
(addrsel_g != 5'h19 && arbin[9] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[10] =
(addrsel_g != 5'h1a && arbin[10] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[11] =
(addrsel_g != 5'h1b && arbin[11] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[12] =
(addrsel_g != 5'h1c && arbin[12] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[13] =
(addrsel_g != 5'h1d && arbin[13] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[14] =
(addrsel_g != 5'h1e && arbin[14] == 1'b1) ? 1'b1 : 1'b0;
assign arbout[15] =
(addrsel_g != 5'h1f && arbin[15] == 1'b1) ? 1'b1 : 1'b0;
assign busy1_n = (arbout != arbin) ? 1'b1 : ~addrsel[4];
assign okstep = (arbout == arbin) ? 1'b1 : 1'b0;
always @(posedge reset)
begin
if (reset == 1'b1)
begin
addrsel <= 5'b0;
addrfsr <= 6'b0;
arbena <= 1'b0;
end
end
always @(posedge clock)
begin
frame1_n <= frame_n;
frame2_n <= frame1_n;
busy_n <= busy1_n;
din1 <= din;
vald1_n <= valid_n | ~busy_n ;
if (reset == 1'b0)
begin
if (frame1_n != frame_n && frame_n == 1'b0)
addrfsr <= 6'b11_1111;
if (frame2_n != frame1_n && frame1_n == 1'b1)
begin // frame is now inactive
addrsel <= 5'b0; // clear the address register
addrfsr <= 6'b0; // clear the address flag reg.
arbena <= 1'b0;
end
else
begin
if (addrsel[4] == 1'b1 && frameo_n[addrsel[3:0]] == 1'b1)
arbena <= 1'b1;
end
if (addrfsr[5:4] == 2'b10)
addrsel <= {
addrsf[0],addrsf[1],addrsf[2],addrsf[3],addrsf[4]};
if (addrfsr[4] == 1'b1) addrsf <= (addrsf << 1) | {
4'b0, din1 };
if (addrfsr[5] == 1'b1) addrfsr <= addrfsr << 1;
end
end
endmodule //rtslicef