Support selecting waveform in genSaw

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Aadi Desai 2023-05-18 12:35:39 +01:00
parent 166e6c913c
commit a17429c105
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2 changed files with 23 additions and 3 deletions

View file

@ -5,6 +5,7 @@ module genSaw
, input var i_rst48_n , input var i_rst48_n
, input var i_pause , input var i_pause
, input var [23:0] i_targetf , input var [23:0] i_targetf
, input var [ 7:0] i_wave
, output var [15:0] o_sample , output var [15:0] o_sample
, output var o_pulse , output var o_pulse
); );
@ -32,8 +33,26 @@ always_comb int_saw_step = (24'd699 * i_targetf); // Sawtooth step calc from inp
logic [15:0] saw_step; logic [15:0] saw_step;
always_comb saw_step = {1'b0, int_saw_step[23:9]}; // Shift step right correctly (2^9) always_comb saw_step = {1'b0, int_saw_step[23:9]}; // Shift step right correctly (2^9)
always_ff @(posedge clk_48k) // Generate new sample on rising edge of 48kHz clock logic [15:0] saw;
if (!i_rst48_n) o_sample <= '0; always_ff @(posedge clk_48k) // Generate new saw sample on rising edge of 48kHz clock
else if (!i_pause) o_sample <= o_sample + saw_step; // Add saw_step if not paused (48kHz) if (!i_rst48_n) saw <= '0;
else if (!i_pause) saw <= saw + saw_step; // Add saw_step if not paused (48kHz)
logic [15:0] square;
always_comb square = {16{saw[15]}};
logic [15:0] triangle;
always_comb triangle = saw[15] ? {16'hFFFF - {saw[14:0], 1'b1}} : {saw[14:0], 1'b0}; // TODO: Optimise?
logic [15:0] sine;
always_comb sine = saw; // TODO: Insert sine calcuation here?
always_comb // Select output waveform
case (i_wave[1:0])
2'd0: o_sample = saw;
2'd1: o_sample = square;
2'd2: o_sample = triangle;
2'd3: o_sample = sine;
endcase
endmodule endmodule

View file

@ -59,6 +59,7 @@ class TestSaw(Module, AutoCSR, ModuleDoc):
i_i_rst48_n = ~ResetSignal(), i_i_rst48_n = ~ResetSignal(),
i_i_pause = self.backpressure_48, i_i_pause = self.backpressure_48,
i_i_targetf = self.targ0.storage, i_i_targetf = self.targ0.storage,
i_i_wave = self.wave0.storage,
o_o_sample = self.sample_48, o_o_sample = self.sample_48,
o_o_pulse = self.audioready_48, o_o_pulse = self.audioready_48,
) )