OpenFPGA/yosys/tests/sat/counters.v

36 lines
515 B
Verilog

module counter1(clk, rst, ping);
input clk, rst;
output ping;
reg [31:0] count;
always @(posedge clk) begin
if (rst)
count <= 0;
else
count <= count + 1;
end
assign ping = &count;
endmodule
module counter2(clk, rst, ping);
input clk, rst;
output ping;
reg [31:0] count;
integer i;
reg carry;
always @(posedge clk) begin
carry = 1;
for (i = 0; i < 32; i = i+1) begin
count[i] <= !rst & (count[i] ^ carry);
carry = count[i] & carry;
end
end
assign ping = &count;
endmodule