something wrong in audio

[LMN128]

something wrong in audio

[mopplayer]

Hi @sameer,

I have created another issue.

Thank you very much.

[sameer]

Hi Jan,

I'm not aware of any particular logic that would cause that. Could you share the changes you made to that code to use 24 bit audio? That way I can look into this issue with the top testbench. Also, did you already try using a non-signed representation?

[LMN128]

Hi Sameer,
sorry for confusion second problem is not related to 24bits audio, but with 44100Hz sample rate. I use this code:

logic clk_audio;
logic [8:0] audio_divider;

always_ff@(posedge clk_pixel) 
begin
if (audio_divider<9'd306-1) audio_divider++; //generated from clk_pixel 27.0000MHz/281=48042,70Hz ; 27.0000MHz/306=44117,64Hz
else  begin clk_audio<=~clk_audio; audio_divider<=0; end
end

logic [23:0] audio_sample_word [1:0] = '{24'sd0, 24'sd0};
always_ff@(posedge clk_audio)
begin
audio_sample_word[0] <= audio_sample_word[0] + 128;  //sawtooth generator
audio_sample_word[1] <= audio_sample_word[1] - 256;  
end 

logic [23:0] rgb = 24'd0;
logic [9:0] cx, cy, screen_start_x, screen_start_y, frame_width, frame_height, screen_width, screen_height;
// Border test (left = red, top = green, right = blue, bottom = blue, fill = black)
always_ff@(posedge clk_pixel)
  rgb <= {cx == screen_start_x ? ~8'd0 : 8'd0, cy == screen_start_y ? ~8'd0 : 8'd0, cx == frame_width - 1'd1 || cy == frame_height - 1'd1 ? ~8'd0 : 8'd0};

hdmi #(.VIDEO_ID_CODE(17), .VIDEO_REFRESH_RATE(50), .AUDIO_RATE(44100), .AUDIO_BIT_WIDTH(24)) hdmi(
  .clk_pixel_x10(clk_pixel_x10),
  .clk_pixel(clk_pixel),
  .clk_audio(clk_audio),
  .rgb(rgb),
  .audio_sample_word(audio_sample_word),
  .tmds_p(dvdata_p),
  .tmds_clock_p(dvclk_p),
  .tmds_n(dvdata_n),
  .tmds_clock_n(dvclk_n),
  .cx(cx),
  .cy(cy),
  .screen_start_x(screen_start_x),
  .screen_start_y(screen_start_y),
  .frame_width(frame_width),
  .frame_height(frame_height),
  .screen_width(screen_width),
  .screen_height(screen_height)
);

and look at how is signal produced.

When I change sample rate to 48000Hz the signal has nice sawtooth shape.

[mopplayer]

Hi,

l think you are successful to set up and show.

I use the test pattern to test, there are always two block shown.

Is my screen not supported? or something wrong?

Did you have some ideas?

https://imgur.com/ArIkfPk

[sameer]

Hi mopplayer, Could you create a separate issue for this? Also, what model of TV/monitor are you using?

…

On Wed, Sep 14, 2022, at 19:42, mopplayer wrote: Hi, l think you are successful to set up and show. I use the test pattern to test, there are always two block shown. Is my screen not supported? or something wrong? Did you have some ideas? https://imgur.com/ArIkfPk — Reply to this email directly, view it on GitHub <#27 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ACUVICGBIJFQ6ERZMLGVE6TV6KEIZANCNFSM5DUAW5XQ>. You are receiving this because you commented.Message ID: ***@***.***>

[sameer]

Should be resolved by 08936f6