diff options
| -rw-r--r-- | filter/Makefile | 27 | ||||
| -rw-r--r-- | filter/top.pcf | 31 | ||||
| -rw-r--r-- | filter/top.v | 127 |
3 files changed, 185 insertions, 0 deletions
diff --git a/filter/Makefile b/filter/Makefile new file mode 100644 index 0000000..195fcbc --- /dev/null +++ b/filter/Makefile @@ -0,0 +1,27 @@ +TOP = top +VS = top.v ../cocotb_try/cic3_pdm.v + +all: check top.bin + +check: + verilator --lint-only --top $(TOP) $(VS) + +clean: + rm -f top.asc top.bin top.json + +gui: + nextpnr-ice40 --hx1k --package tq144 --json top.json --pcf top.pcf --asc top.asc --top $(TOP) --gui + +load: all + iceprog top.bin + +.PHONY: all check clean gui load + +top.asc: top.json top.pcf + nextpnr-ice40 --hx1k --package tq144 --json top.json --pcf top.pcf --asc top.asc --top $(TOP) + +top.bin: top.asc + icepack top.asc top.bin + +top.json: $(VS) + yosys -q -p "synth_ice40 -json top.json -top $(TOP)" $(VS) diff --git a/filter/top.pcf b/filter/top.pcf new file mode 100644 index 0000000..0acfcd4 --- /dev/null +++ b/filter/top.pcf @@ -0,0 +1,31 @@ +set_io ftdi_tx 8 +set_io ftdi_rx 9 + +set_io clk 21 + +set_io p44 44 +set_io p45 45 +set_io p47 47 +set_io p48 48 +set_io p56 56 +set_io p60 60 +set_io p61 61 +set_io p62 62 + +set_io p112 112 +set_io p113 113 +set_io p114 114 +set_io p115 115 +set_io p116 116 +set_io p117 117 +set_io p118 118 +set_io p119 119 + +set_io D5 95 +set_io D1 96 +set_io D2 97 +set_io D3 98 +set_io D4 99 + +set_io pdm_clk 80 +set_io pdm_dat 79 diff --git a/filter/top.v b/filter/top.v new file mode 100644 index 0000000..12859ed --- /dev/null +++ b/filter/top.v @@ -0,0 +1,127 @@ +module top( + input clk, + input ftdi_rx, + output D1, + output D2, + output D3, + output D4, + output D5, + output ftdi_tx, + output p44, + output p45, + output pdm_clk, + input pdm_dat +); + wire clk_uart; + + reg rst = 0; + reg [7:0] char = 8'h6f; + reg [15:0] pcm; + reg pcm_valid; + reg uart_go = 0; + wire uart_ready; + + clk_div_pdm clk_div_pdm_1(clk, pdm_clk); + clk_div_uart clk_div_uart_1(clk, clk_uart); + uart_tx uart_tx_1(clk_uart, char, uart_go, ftdi_tx, uart_ready); + cic3_pdm cic3_pdm_1(pdm_clk, rst, pdm_dat, pcm, pcm_valid); + + always @(posedge pdm_clk) begin + char <= pcm[7:0]; + uart_go <= pcm_valid; + end + + assign D1 = 0; + assign D2 = 0; + assign D3 = 0; + assign D4 = 0; + assign D5 = 1; + assign p44 = 0; + assign p45 = 0; +endmodule + +module clk_div_pdm(input clk, output reg clk_pdm); + reg [3:0] t = 0; + always @(posedge clk) begin + t <= t<12-1 ? t+1 : 0; + clk_pdm <= t<6; + end +endmodule + +module rot(input clk, output [3:0] d); + reg [3:0] r = 4'b1000; + always @(posedge clk) r <= {r[0], r[3:1]}; + assign d = r; +endmodule + +module clk_div_uart(input clk, output reg clk_uart); + reg [3:0] t = 0; + always @(posedge clk) begin + t <= t<4-1 ? t+1 : 0; + clk_uart <= t<2; + end +endmodule + +module uart_tx(input clk, input [7:0] char, input go, output reg tx, output reg ready); + parameter s_ready = 0; + parameter s_start = 1; + parameter s_data0 = 2; + parameter s_data1 = 3; + parameter s_data2 = 4; + parameter s_data3 = 5; + parameter s_data4 = 6; + parameter s_data5 = 7; + parameter s_data6 = 8; + parameter s_data7 = 9; + parameter s_stop1 = 10; + parameter s_stop2 = 11; + parameter s_stop3 = 12; + parameter s_stop4 = 13; + + reg [3:0] state = s_ready; + reg [7:0] data = 8'h41; + + always @(posedge clk) begin + ready <= state == s_ready; + case (state) + s_ready: begin + if (go) begin + data <= char; + state <= s_start; + end + end + s_start: state <= s_data0; + s_data0: state <= s_data1; + s_data1: state <= s_data2; + s_data2: state <= s_data3; + s_data3: state <= s_data4; + s_data4: state <= s_data5; + s_data5: state <= s_data6; + s_data6: state <= s_data7; + s_data7: state <= s_stop1; + s_stop1: state <= s_stop2; + s_stop2: state <= s_stop3; + s_stop3: state <= s_stop4; + s_stop4: begin + if (!go) + state <= s_ready; + end + endcase + case (state) + s_ready: tx <= 1; + s_start: tx <= 0; + s_data0: tx <= data[0]; + s_data1: tx <= data[1]; + s_data2: tx <= data[2]; + s_data3: tx <= data[3]; + s_data4: tx <= data[4]; + s_data5: tx <= data[5]; + s_data6: tx <= data[6]; + s_data7: tx <= data[7]; + s_stop1: tx <= 1; + s_stop2: tx <= 1; + s_stop3: tx <= 1; + s_stop4: tx <= 1; + endcase + end +endmodule |