基于FPGA的温度监控系统 - 图文

山东科技大学学士学位论文 附录

dq_out <= data_w[cnt_bit]; end else if(cnt < 'd65) begin link <= 0; end else begin cnt <= 0; cnt_bit <= cnt_bit + 1; if(cnt_bit == 'd7) begin cnt_bit <= 0; state <= WAIT_800MS; end end end

WAIT_800MS: begin cnt <= cnt + 1; if(cnt == 'd800000) begin cnt <= 0; state <= RESET2; end end

RESET2: begin cnt <= cnt + 1; if(cnt < 'd500) begin link <= 1; dq_out <= 0; end else if(cnt < 'd1000) begin link <= 0; end else begin cnt <= 0;

state <= WRITE_CC2;

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//等待800ms //第二次复位 山东科技大学学士学位论文 附录

data_w <= 8'hcc; cnt_bit <= 0; end end

WRITE_CC2: begin //吸入跳过rom命令 cnt <= cnt + 1; if(cnt < 'd5) begin link <= 1; dq_out <= 0; end else if(cnt < 'd60) begin dq_out <= data_w[cnt_bit]; end else if(cnt < 'd65) begin link <= 0; end else begin cnt <= 0; cnt_bit <= cnt_bit + 1; if(cnt_bit == 'd7) begin state <= WRITE_BE; cnt_bit <= 0; data_w <= 8'hbe; end end end

WRITE_BE: begin cnt <= cnt + 1; if(cnt < 'd5) begin link <= 1; dq_out <= 0; end

else if(cnt < 'd60)

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//写入读数据命令 山东科技大学学士学位论文 附录

begin dq_out <= data_w[cnt_bit]; end else if(cnt < 'd65) begin link <= 0; end else begin cnt <= 0; cnt_bit <= cnt_bit + 1; if(cnt_bit == 'd7) begin state <= READ1; cnt_bit <= 0; end end end

READ1: begin cnt <= cnt + 1; if(cnt < 'd3) begin link <= 1; dq_out <= 0; end else if(cnt == 'd3) link <= 0; else if(cnt == 'd12) data_r[cnt_bit] <= dq_in; else if(cnt > 'd65) begin cnt <= 0; cnt_bit <= cnt_bit + 1; if(cnt_bit == 'd7) begin cnt_bit <= 0; temp[7:0] <= data_r; state <= READ2;

end

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//读入第一个字节 山东科技大学学士学位论文 附录

end end READ2:

begin //读入第二个字节 cnt <= cnt + 1; if(cnt < 'd3) begin link <= 1; dq_out <= 0; end else if(cnt == 'd3) link <= 0; else if(cnt == 'd12) data_r[cnt_bit] <= dq_in; else if(cnt > 'd65) begin cnt <= 0; cnt_bit <= cnt_bit + 1; if(cnt_bit == 'd7) begin cnt_bit <= 0; temp[15:8] <= data_r; state <= RESET1; end end end endcase end

endmodule 分频模块： module clk_gen( input rst, input clk, output reg clk_1k, output reg clk_1m ); reg[14:0] cnt_1k;

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