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06d6505d11
* Put them all under a `verilog` directory. * Move the common `pcf` files to the top. * Rename to `blink-basic` and `blink-expanded`.
154 lines
4.3 KiB
Verilog
154 lines
4.3 KiB
Verilog
// Simple tri-colour LED blink example, with button control
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//
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// Green LED blinks forever.
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// Blue LED turned on when Button 5 is pressed.
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// Red LED turned on when Button 6 is pressed.
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//
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`define BLUEPWM RGB0PWM
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`define GREENPWM RGB1PWM
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`define REDPWM RGB2PWM
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module top (
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// 48MHz Clock input
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// --------
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input clki,
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// LED outputs
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// --------
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output rgb0,
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output rgb1,
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output rgb2,
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// User touchable pins
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// --------
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// Connect 1-2 to enable blue LED
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input user_1,
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output user_2,
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// Connect 3-4 to enable red LED
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output user_3,
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input user_4,
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// USB Pins (which should be statically driven if not being used).
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// --------
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output usb_dp,
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output usb_dn,
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output usb_dp_pu
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);
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// Drive the USB outputs to constant values as they are not in use.
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assign usb_dp = 1'b0;
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assign usb_dn = 1'b0;
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assign usb_dp_pu = 1'b0;
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// Connect to system clock (with buffering)
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wire clkosc;
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SB_GB clk_gb (
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.USER_SIGNAL_TO_GLOBAL_BUFFER(clki),
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.GLOBAL_BUFFER_OUTPUT(clkosc)
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);
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wire clk = clkosc;
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// Configure user pins so that we can detect the user connecting
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// 1-2 or 3-4 with conductive material.
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//
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// We do this by grounding user_2 and user_3, and configuring inputs
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// with pullups on user_1 and user_4.
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localparam SB_IO_TYPE_SIMPLE_INPUT = 6'b000001;
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wire user_1_pulled;
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SB_IO #(
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.PIN_TYPE(SB_IO_TYPE_SIMPLE_INPUT),
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.PULLUP(1'b1)
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) user_1_io (
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.PACKAGE_PIN(user_1),
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.OUTPUT_ENABLE(1'b0),
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.INPUT_CLK(clk),
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.D_IN_0(user_1_pulled),
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);
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assign user_2 = 1'b0;
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assign user_3 = 1'b0;
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wire user_4_pulled;
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SB_IO #(
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.PIN_TYPE(SB_IO_TYPE_SIMPLE_INPUT),
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.PULLUP(1'b 1)
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) user_4_io (
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.PACKAGE_PIN(user_4),
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.OUTPUT_ENABLE(1'b0),
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.INPUT_CLK(clk),
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.D_IN_0(user_4_pulled),
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);
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wire enable_blue = ~user_1_pulled;
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wire enable_red = ~user_4_pulled;
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// Use system PLL module to divide system clock
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wire pll_out;
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SB_PLL40_CORE #(
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.FEEDBACK_PATH("SIMPLE"),
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.DIVR(4'b0010), // DIVR = 2
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.DIVF(7'b0110001), // DIVF = 49
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.DIVQ(3'b010), // DIVQ = 2
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.FILTER_RANGE(3'b001) // FILTER_RANGE = 1
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) pll (
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.RESETB(1'b1),
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.BYPASS(1'b0),
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.REFERENCECLK(clk),
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.PLLOUTCORE(pll_out),
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);
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// Use counter logic to divide system clock
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// (for blinking LED state)
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//
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// BITS controls LED state
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// LOG2DELAY controls divisor
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// -- requires counting to 2**LOG2DELAY before spilling onto LED state BITS
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//
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localparam BITS = 5;
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localparam LOG2DELAY = 21;
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reg [28:0] counter = 0;
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reg [BITS-1:0] outcnt;
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always @(posedge clk) begin
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counter <= counter + 1;
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outcnt <= counter >> LOG2DELAY;
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end
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// Instantiate iCE40 LED driver hard logic, connecting up
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// latched button state, counter state, and LEDs.
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SB_RGBA_DRV RGBA_DRIVER (
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.CURREN(1'b1),
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.RGBLEDEN(1'b1),
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.`BLUEPWM(enable_blue), // Blue
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.`REDPWM(enable_red), // Red
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.`GREENPWM(counter[23]), // Green (blinking)
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.RGB0(rgb0),
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.RGB1(rgb1),
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.RGB2(rgb2)
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);
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// Parameters from iCE40 UltraPlus LED Driver Usage Guide, pages 19-20
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//
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// https://www.latticesemi.com/-/media/LatticeSemi/Documents/ApplicationNotes/IK/ICE40LEDDriverUsageGuide.ashx?document_id=50668
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localparam RGBA_CURRENT_MODE_FULL = "0b0";
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localparam RGBA_CURRENT_MODE_HALF = "0b1";
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// Current levels in Full / Half mode
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localparam RGBA_CURRENT_04MA_02MA = "0b000001";
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localparam RGBA_CURRENT_08MA_04MA = "0b000011";
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localparam RGBA_CURRENT_12MA_06MA = "0b000111";
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localparam RGBA_CURRENT_16MA_08MA = "0b001111";
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localparam RGBA_CURRENT_20MA_10MA = "0b011111";
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localparam RGBA_CURRENT_24MA_12MA = "0b111111";
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// Set parameters of RGBA_DRIVER (output current)
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//
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// Mapping of RGBn to LED colours determined experimentally
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defparam RGBA_DRIVER.CURRENT_MODE = RGBA_CURRENT_MODE_HALF;
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defparam RGBA_DRIVER.RGB0_CURRENT = RGBA_CURRENT_16MA_08MA; // Blue - Needs more current.
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defparam RGBA_DRIVER.RGB1_CURRENT = RGBA_CURRENT_08MA_04MA; // Red
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defparam RGBA_DRIVER.RGB2_CURRENT = RGBA_CURRENT_08MA_04MA; // Green
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endmodule
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