Re: "is not declared under this prefix"

SFalk3 · ‎05-05-2020

Hello all,

I'm getting the following errors during Analysis and Synthesis and I can't find much about them using Google.

Error (10733): Verilog HDL error at spi_shapes_to_video.sv(67): color is not declared under this prefix
Error (10733): Verilog HDL error at spi_shapes_to_video.sv(86): y is not declared under this prefix

If it's relevant, the file that is being referred to is part of a generated component under Platform Designer.

Here is the source file spi_shapes_to_video.sv

module spi_shapes_to_video (
		input  wire        spi_clk_clk,                //      spi_clk.clk
		input  wire        video_clk_clk,              //    video_clk.clk
		input  wire        spi_rst_reset,              //      spi_rst.reset
		input  wire        video_rst_reset,            //    video_rst.reset
		input  wire [7:0]  spi_sink_data,              //     spi_sink.data
		input  wire        spi_sink_valid,             //             .valid
		input  wire        video_source_ready,         //             .ready
		output logic        spi_sink_ready,             //             .ready
		output logic [15:0] video_source_data,          // video_source.data
		output logic        video_source_startofpacket, //             .startofpacket
		output logic        video_source_endofpacket,   //             .endofpacket
		output logic        video_source_valid          //             .valid
	);
 
    localparam NUM_LINES_WIDTH = 10;
    localparam NUM_LINES = 1 << NUM_LINES_WIDTH;
    localparam SCREEN_WIDTH = 640;
    localparam SCREEN_HEIGHT = 480;
    localparam COLOR_BG = 16'b0;
 
    typedef enum {
        STATE_PRE_INPUT,
        STATE_INPUT,
        STATE_PRE_OUTPUT,
        STATE_OUTPUT
    } state_t;
 
    typedef struct packed {
        logic [3:0] alpha;
        logic [3:0] r;
        logic [3:0] g;
        logic [3:0] b;
    } color_t;
 
    typedef struct packed {
        logic [9:0] x;
        logic [8:0] y;
    } point_t;
 
    typedef struct packed {
        logic [1:0] align_bits;
        point_t start_point;
        point_t end_point;
        color_t color;
    } line_t;
 
    function line_has_point (
        input point_t point,
        input line_t line
    );
 
        line_has_point = (point.y - line.start_point.y) * (line.end_point.x - line.start_point.x) 
            == (point.x - line.start_point.x) * (line.end_point.y - line.start_point.y);
    endfunction
 
    function color_t get_color(
        input point_t point
    );
        
        integer i;
        color_t out;
        begin
            out = COLOR_BG;
            for (i = 0; i < NUM_LINES; i++) begin
                if (line_has_point(point, lines[i])) out = lines[i].color;
            end
            get_color = out;
        end
    endfunction
 
    function state_t get_next_state(
        input state_t state
    );
        case(state)
            STATE_PRE_INPUT:
                get_next_state = STATE_INPUT;
            STATE_INPUT:
                if (lines_index == NUM_LINES)
                    get_next_state = STATE_PRE_OUTPUT;
                else get_next_state = STATE_INPUT;
            STATE_PRE_OUTPUT:
                get_next_state = STATE_OUTPUT;
            STATE_OUTPUT:
                if (current_point.y == SCREEN_HEIGHT)
                    get_next_state = STATE_PRE_INPUT;
                else get_next_state = STATE_OUTPUT;
            default: get_next_state = STATE_PRE_INPUT;
        endcase
    endfunction
 
    state_t state;
    logic [1:0] video_clk_vals;
    line_t [NUM_LINES-1:0] lines  /* synthesis ramstyle = "M9K" */;
 
    logic [NUM_LINES_WIDTH:0] lines_index;
    logic [2:0] line_byte_count;
 
    point_t current_point;
 
    always @(posedge spi_clk_clk) begin
        if (~spi_rst_reset) begin
            lines = 0;
            lines_index = 0;
            line_byte_count = 0;
            video_clk_vals = 2'b0;
            state = STATE_PRE_INPUT;
            current_point = 0;
 
            spi_sink_ready = 1'b0;
            video_source_valid = 1'b0;
            video_source_data = 16'b0;
            video_source_startofpacket = 1'b0;
            video_source_endofpacket = 1'b0;
        end else begin
            video_clk_vals = {video_clk_vals[0], video_clk_clk};
            state = get_next_state(state);
            case(state)
                STATE_PRE_INPUT: begin
                    lines_index = 0;
                end
                STATE_INPUT: begin
                    spi_sink_ready = 1'b1;
                    video_source_valid = 1'b0;
                    if (spi_sink_valid) begin
                        lines[lines_index] = {lines[lines_index][47:0], spi_sink_data};
                        line_byte_count += 1;
                    end
                    if (line_byte_count == 7) begin
                        lines_index += 1;
                        line_byte_count = 0;
                    end
                end
                STATE_PRE_OUTPUT: begin
                    spi_sink_ready = 1'b0;
                    current_point = 0;
                end
                STATE_OUTPUT: begin
                    // negedge of video clock
                    if (video_clk_vals == 2'b10) begin
                        if (video_source_ready) begin
                            video_source_valid = 1;
                            video_source_data = get_color(current_point);
 
                            video_source_startofpacket = current_point == 0;
                            video_source_endofpacket = current_point.x == SCREEN_WIDTH - 1 && 
                                current_point.y == SCREEN_HEIGHT - 1;
 
                            current_point.x += 1;
                            if (current_point.x == SCREEN_WIDTH) begin
                                current_point.x = 0;
                                current_point.y += 1;
                            end
                        end else begin
                            video_source_valid = 0;
                        end
                    end
                end
            endcase
        end
    end
endmodule

Thanks for any help with this... I have no idea what the issue is.

RichardTanSY_Intel · ‎05-05-2020

The error code meant to fix the problem identified by the message text.

Could you share your project so I can further check on this?

SFalk3 · ‎05-05-2020

Hello, thanks for your response. I've attached the project to this message. I am using Quartus Prime Lite version 18.1.

SFalk3 · ‎05-05-2020

Okay I fixed the issue by not referencing variables outside the scope of the function. So I passed in lines as an argument to get_color and current_point as an argument to get_next_state. Still, I wonder why this is necessary. I thought that I should be able to access module variables from within a module function.

RichardTanSY_Intel · ‎05-12-2020

I found out if I relocate these two lines. (see attached) It seems to pass the error.