leds.h

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/*a Constants */
constant bit[16] led_seven_seg_hex_a = 16b_1101011111101101 "Which hex values require lighting of LED segment A";
constant bit[16] led_seven_seg_hex_b = 16b_0010011110011111 "Which hex values require lighting of LED segment B";
constant bit[16] led_seven_seg_hex_c = 16b_0010111111111011 "Which hex values require lighting of LED segment C";
constant bit[16] led_seven_seg_hex_d = 16b_0111101101101101 "Which hex values require lighting of LED segment D";
constant bit[16] led_seven_seg_hex_e = 16b_1111110101000101 "Which hex values require lighting of LED segment E";
constant bit[16] led_seven_seg_hex_f = 16b_1101111101110001 "Which hex values require lighting of LED segment F";
constant bit[16] led_seven_seg_hex_g = 16b_1110111101111100 "Which hex values require lighting of LED segment G";

/*a Types */
/*t t_led_ws2812_data
 *
 * LED data response to the led_ws2812_chain module, indicating the
 * 24-bit RGB value for the @a led_number'th LED in the chain
 *
 */
typedef struct {
    bit valid     "Assert if the LED data supplied in this structure is valid";
    bit last      "Assert if the LED data is for the last LED in the chain";
    bit[8] red    "The 8 bit red component for the LED to display";
    bit[8] green  "The 8 bit green component for the LED to display";
    bit[8] blue   "The 8 bit blue component for the LED to display";
} t_led_ws2812_data;

/*t t_led_ws2812_request
 *
 * Request from the led_ws2812_chain module to ask for the color data
 * for a particular LED in the LED chain
 */
typedef struct {
    bit ready          "Active high signal indicating if LED data is required; ignore @a ready if the response has @a valid asserted";
    bit first          "If requesting LED data, then the first LED of the stream should be provided; indicates @a led_number is 0";
    bit[8] led_number  "Number of LED data required, so that a client can use a switch statement or register file or array, for example";
} t_led_ws2812_request;

/*a Modules */
/*m led_seven_segment*/
extern module led_seven_segment( input bit[4] hex   "Hexadecimal to display on 7-segment LED",
                                 output bit[7] leds "1 for LED on, 0 for LED off, for segments a-g in bits 0-7"
    )
{
    timing comb input hex;
    timing comb output leds;
}

/*m led_ws2812_chain*/
extern module led_ws2812_chain( clock clk                   "system clock - not the pin clock",
                                input bit    reset_n  "async reset",
                                input bit[8] divider_400ns  "clock divider value to provide for generating a pulse every 400ns based on clk",
                                output t_led_ws2812_request led_request  "LED data request",
                                input t_led_ws2812_data     led_data     "LED data, for the requested led",
                                output bit led_chain                     "Data in pin for LED chain"
    )
{
    timing to   rising clock clk  divider_400ns, led_data;
    timing from rising clock clk  led_request, led_chain;
}