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Fix HDMI sink compatibility for Samsung TVs and strict monitors #38

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Fix HDMI sink compatibility for Samsung TVs and strict monitors #38

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5 changes: 1 addition & 4 deletions hdl/hdmi/audio_clock_regeneration_packet.sv
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Original file line number Diff line number Diff line change
Expand Up @@ -57,11 +57,8 @@ begin
end

// "An HDMI Sink shall ignore bytes HB1 and HB2 of the Audio Clock Regeneration Packet header."
`ifdef MODEL_TECH
// Use deterministic zero values so BCH ECC is consistent in synthesis.
assign header = {8'd0, 8'd0, 8'd1};
`else
assign header = {8'dX, 8'dX, 8'd1};
`endif

// "The four Subpackets each contain the same Audio Clock regeneration Subpacket."
genvar i;
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2 changes: 1 addition & 1 deletion hdl/hdmi/hdmi.sv
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Expand Up @@ -321,7 +321,7 @@ generate
begin
mode <= 3'd2;
video_data <= 24'd0;
control_data = 6'd0;
control_data <= 6'd0;
data_island_data <= 12'd0;
end
else
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28 changes: 17 additions & 11 deletions hdl/hdmi/packet_picker.sv
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Expand Up @@ -36,15 +36,9 @@ assign sub[3] = subs[packet_type][3];

// NULL packet
// "An HDMI Sink shall ignore bytes HB1 and HB2 of the Null Packet Header and all bytes of the Null Packet Body."
`ifdef MODEL_TECH
assign headers[0] = {8'd0, 8'd0, 8'd0}; assign subs[0] = '{56'd0, 56'd0, 56'd0, 56'd0};
`else
assign headers[0] = {8'dX, 8'dX, 8'd0};
assign subs[0][0] = 56'dX;
assign subs[0][1] = 56'dX;
assign subs[0][2] = 56'dX;
assign subs[0][3] = 56'dX;
`endif
// Use deterministic zero values so BCH ECC is consistent in synthesis.
assign headers[0] = {8'd0, 8'd0, 8'd0};
assign subs[0] = '{56'd0, 56'd0, 56'd0, 56'd0};

// Audio Clock Regeneration Packet
logic clk_audio_counter_wrap;
Expand Down Expand Up @@ -135,7 +129,19 @@ audio_sample_packet #(.SAMPLING_FREQUENCY(SAMPLING_FREQUENCY), .WORD_LENGTH({{WO

auxiliary_video_information_info_frame #(
.VIDEO_ID_CODE(7'(VIDEO_ID_CODE)),
.IT_CONTENT(IT_CONTENT)
.IT_CONTENT(IT_CONTENT),
// CTA-861 requires PICTURE_ASPECT_RATIO to match the VIC.
// VIC 2 = 4:3, VIC 3 = 16:9. Leaving this at "no data" (2'b00)
// caused some HDMI sinks (e.g. Ingnok) to reject the signal.
.PICTURE_ASPECT_RATIO(VIDEO_ID_CODE == 3 ? 2'b10 : 2'b01),
// Samsung TVs require ACTIVE_FORMAT_INFO_PRESENT=1 with R3-R0=1000
// ("same as coded frame") or they may reject the signal.
.ACTIVE_FORMAT_INFO_PRESENT(1'b1),
// Tell the sink this is underscan content (pixel-accurate, no overscan).
.SCAN_INFO(2'b10),
// Explicitly signal full-range RGB (0-255). Samsung TVs need this
// rather than relying on the IT_CONTENT flag to imply full range.
.RGB_QUANTIZATION_RANGE(2'b10)
) auxiliary_video_information_info_frame(.header(headers[130]), .sub(subs[130]));


Expand All @@ -160,7 +166,7 @@ begin
audio_info_frame_sent <= 1'b0;
auxiliary_video_information_info_frame_sent <= 1'b0;
source_product_description_info_frame_sent <= 1'b0;
packet_type <= 8'dx;
packet_type <= 8'd0;
end
else if (packet_enable)
begin
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