2019-02-16 22:38:44 +01:00
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`ifndef _SATURN_BUS_CTRL
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`define _SATURN_BUS_CTRL
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`include "def-clocks.v"
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`include "def-buscmd.v"
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module saturn_bus_ctrl (
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// basic stuff
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i_clk,
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i_reset,
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i_cycle_ctr,
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i_en_bus_send,
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i_en_bus_recv,
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2019-02-17 08:35:26 +01:00
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i_en_bus_ecmd,
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2019-02-16 22:38:44 +01:00
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i_stalled,
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i_read_stall,
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o_stalled_by_bus,
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// bus i/o
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i_bus_data,
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o_bus_data,
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o_bus_strobe,
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o_bus_cmd_data,
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// interface to the rest of the machine
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i_alu_pc,
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i_address,
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i_load_pc,
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2019-02-17 20:23:43 +01:00
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i_cmd_load_dp,
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2019-02-17 12:05:38 +01:00
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i_read_pc,
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2019-02-18 07:43:36 +01:00
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i_cmd_dp_read,
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2019-02-17 20:23:43 +01:00
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i_cmd_dp_write,
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2019-02-17 15:03:36 +01:00
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i_cmd_reset,
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2019-02-17 19:29:39 +01:00
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i_cmd_config,
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2019-02-16 22:38:44 +01:00
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i_nibble,
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o_nibble
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);
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input wire [0:0] i_clk;
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input wire [0:0] i_reset;
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input wire [31:0] i_cycle_ctr;
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input wire [0:0] i_en_bus_send;
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input wire [0:0] i_en_bus_recv;
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2019-02-17 08:35:26 +01:00
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input wire [0:0] i_en_bus_ecmd;
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2019-02-16 22:38:44 +01:00
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input wire [0:0] i_stalled;
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input wire [0:0] i_read_stall;
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2019-02-17 08:35:26 +01:00
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2019-02-16 22:38:44 +01:00
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output reg [0:0] o_stalled_by_bus;
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input wire [3:0] i_bus_data;
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output reg [3:0] o_bus_data;
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output reg [0:0] o_bus_strobe;
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output reg [0:0] o_bus_cmd_data;
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input wire [19:0] i_alu_pc;
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input wire [19:0] i_address;
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input wire [0:0] i_load_pc;
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2019-02-17 20:23:43 +01:00
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input wire [0:0] i_cmd_load_dp;
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2019-02-17 12:05:38 +01:00
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input wire [0:0] i_read_pc;
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2019-02-18 07:43:36 +01:00
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input wire [0:0] i_cmd_dp_read;
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2019-02-17 20:23:43 +01:00
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input wire [0:0] i_cmd_dp_write;
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2019-02-17 15:03:36 +01:00
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input wire [0:0] i_cmd_reset;
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2019-02-17 19:29:39 +01:00
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input wire [0:0] i_cmd_config;
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2019-02-16 22:38:44 +01:00
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input wire [3:0] i_nibble;
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output reg [3:0] o_nibble;
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2019-02-18 11:36:28 +01:00
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/******************************************************************************
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*
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* clocking enables
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*
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****************************************************************************/
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wire en_bus_send;
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wire en_bus_recv;
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wire en_bus_ecmd;
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2019-02-16 22:38:44 +01:00
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assign en_bus_send = i_en_bus_send && !i_stalled;
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assign en_bus_recv = i_en_bus_recv && !i_stalled;
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2019-02-17 08:35:26 +01:00
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assign en_bus_ecmd = i_en_bus_ecmd && !i_stalled;
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2019-02-16 22:38:44 +01:00
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2019-02-18 11:36:28 +01:00
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/******************************************************************************
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*
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* state machine events
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*
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****************************************************************************/
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2019-02-17 19:29:39 +01:00
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2019-02-18 11:36:28 +01:00
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// declarations
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reg [0:0] cmd_pc_read_s;
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reg [0:0] dp_read_s;
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reg [0:0] cmd_dp_write_s;
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reg [0:0] cmd_load_dp_s;
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2019-02-17 19:29:39 +01:00
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reg [0:0] cmd_config_s;
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reg [0:0] cmd_reset_s;
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2019-02-18 11:36:28 +01:00
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wire [0:0] addr_s;
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2019-02-17 21:20:18 +01:00
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wire [0:0] do_cmd_pc_read;
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wire [0:0] do_display_stalled;
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2019-02-17 19:29:39 +01:00
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2019-02-17 20:23:43 +01:00
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wire [0:0] do_cmd_load_dp;
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2019-02-18 07:43:36 +01:00
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wire [0:0] do_dp_read_data;
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wire [0:0] do_dp_read_data_sc;
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wire [0:0] do_dp_read_data_uc;
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wire [0:0] do_pc_read_after_dp_read;
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wire [0:0] do_cleanup_after_dp_read;
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2019-02-17 20:23:43 +01:00
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wire [0:0] do_cmd_dp_write;
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2019-02-17 21:20:18 +01:00
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wire [0:0] do_dp_write_data;
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2019-02-17 20:23:43 +01:00
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wire [0:0] do_pc_read_after_dp_write;
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wire [0:0] cmd_load_dp_dp_write_uc;
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2019-02-17 19:29:39 +01:00
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wire [0:0] do_cmd_config;
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wire [0:0] do_pc_read_after_config;
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wire [0:0] cmd_config_sc;
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wire [0:0] cmd_config_uc;
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wire [0:0] do_cmd_reset;
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wire [0:0] do_pc_read_after_reset;
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wire [0:0] cmd_reset_sc;
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wire [0:0] cmd_reset_uc;
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2019-02-17 20:23:43 +01:00
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wire [0:0] do_unstall;
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2019-02-18 07:43:36 +01:00
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wire [0:0] do_cleanup;
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2019-02-17 20:23:43 +01:00
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2019-02-18 11:36:28 +01:00
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// assigns
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assign addr_s = addr_cnt == 5;
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2019-02-17 20:23:43 +01:00
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assign do_cmd_load_dp = i_cmd_load_dp && !cmd_load_dp_s;
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2019-02-18 07:43:36 +01:00
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assign do_dp_read_data = i_cmd_dp_read && cmd_load_dp_s && (addr_s || dp_read_s);
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assign do_dp_read_data_sc = i_cmd_dp_read && cmd_load_dp_s && addr_s && !dp_read_s;
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assign do_dp_read_data_uc = i_cmd_dp_read && cmd_load_dp_s && addr_s && dp_read_s;
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assign do_pc_read_after_dp_read = i_read_stall && !i_cmd_dp_read && cmd_load_dp_s && !addr_s && dp_read_s;
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assign do_cleanup_after_dp_read = !i_read_stall && !i_cmd_dp_read && cmd_load_dp_s && !addr_s && dp_read_s;
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2019-02-17 20:23:43 +01:00
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assign do_cmd_dp_write = i_cmd_dp_write && cmd_load_dp_s && addr_s && !cmd_dp_write_s;
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2019-02-17 21:20:18 +01:00
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assign do_dp_write_data = i_cmd_dp_write && cmd_load_dp_s && addr_s && cmd_dp_write_s;
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2019-02-17 20:23:43 +01:00
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assign do_pc_read_after_dp_write = !i_cmd_dp_write && cmd_load_dp_s && cmd_dp_write_s;
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assign cmd_load_dp_dp_write_uc = cmd_load_dp_s && cmd_dp_write_s && cmd_pc_read_s;
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2019-02-17 19:29:39 +01:00
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2019-02-17 20:23:43 +01:00
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assign do_cmd_config = i_cmd_config && !cmd_config_s;
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assign do_pc_read_after_config = i_cmd_config && cmd_config_s && addr_s;
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assign cmd_config_sc = !o_stalled_by_bus && i_cmd_config && !cmd_config_s;
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assign cmd_config_uc = cmd_config_s && cmd_pc_read_s;
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2019-02-17 19:29:39 +01:00
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2019-02-17 20:23:43 +01:00
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assign do_cmd_reset = i_cmd_reset && !cmd_reset_s;
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assign do_pc_read_after_reset = i_cmd_reset && cmd_reset_s;
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assign cmd_reset_sc = !o_stalled_by_bus && i_cmd_reset && !cmd_reset_s;
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assign cmd_reset_uc = cmd_reset_s && cmd_pc_read_s;
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2019-02-17 19:29:39 +01:00
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2019-02-17 21:20:18 +01:00
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assign do_cmd_pc_read = !cmd_pc_read_s &&
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2019-02-18 07:43:36 +01:00
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(do_pc_read_after_dp_read ||
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do_pc_read_after_dp_write ||
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do_pc_read_after_config ||
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do_pc_read_after_reset);
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2019-02-18 11:36:28 +01:00
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assign do_display_stalled = en_bus_recv && i_read_stall && !o_stalled_by_bus &&
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2019-02-17 21:20:18 +01:00
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!(do_cmd_pc_read ||
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do_dp_read_data ||
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do_pc_read_after_dp_read ||
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do_cmd_dp_write ||
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do_dp_write_data ||
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do_pc_read_after_dp_write);
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2019-02-18 07:43:36 +01:00
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assign do_unstall = do_dp_read_data_uc ||
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cmd_load_dp_dp_write_uc ||
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cmd_config_uc ||
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cmd_reset_uc;
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assign do_cleanup = do_cleanup_after_dp_read ||
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cmd_load_dp_dp_write_uc ||
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2019-02-17 20:23:43 +01:00
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cmd_config_uc ||
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cmd_reset_uc;
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2019-02-18 11:36:28 +01:00
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/******************************************************************************
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*
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* test rom
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*
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****************************************************************************/
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2019-02-16 22:38:44 +01:00
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`ifdef SIM
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`define ROMBITS 20
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`else
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`define ROMBITS 16
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`endif
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reg [3:0] rom [0:2**`ROMBITS-1];
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2019-02-18 11:36:28 +01:00
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wire [0:0] last_cmd_pc_read;
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wire [0:0] last_cmd_dp_read;
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wire [0:0] do_read_from_bus;
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wire [0:0] use_pc_as_pointer;
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wire [`ROMBITS-1:0] read_pointer;
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assign last_cmd_pc_read = (last_cmd == `BUSCMD_PC_READ);
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assign last_cmd_dp_read = (last_cmd == `BUSCMD_DP_READ);
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assign do_read_from_bus = en_bus_recv && (!i_read_stall || do_dp_read_data) && (last_cmd_pc_read || last_cmd_dp_read);
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assign use_pc_as_pointer = last_cmd_pc_read ;
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assign read_pointer = use_pc_as_pointer?local_pc[`ROMBITS-1:0]:local_dp[`ROMBITS-1:0];
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/******************************************************************************
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*
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* the controller itself
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*
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****************************************************************************/
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2019-02-16 22:38:44 +01:00
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initial begin
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2019-02-18 11:36:28 +01:00
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// `ifdef SIM
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$readmemh("rom-gx-r.hex", rom, 0, 2**`ROMBITS-1);
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2019-02-16 22:38:44 +01:00
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// $readmemh( "testrom-2.hex", rom);
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2019-02-17 12:05:38 +01:00
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2019-02-18 11:36:28 +01:00
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`ifdef SIM
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2019-02-18 07:43:36 +01:00
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// $monitor({"o_stalled_by_bus %b | i_read_stall %b | i_cmd_dp_read %b |",
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// " cmd_load_dp_s %b | addr_s %b | dp_read_s %b |do_dp_read_data %b"},
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// o_stalled_by_bus, i_read_stall, i_cmd_dp_read, cmd_load_dp_s,
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// addr_s, dp_read_s, do_dp_read_data);
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2019-02-16 22:38:44 +01:00
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`endif
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end
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2019-02-17 12:05:38 +01:00
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reg [3:0] last_cmd;
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reg [2:0] addr_cnt;
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reg [0:0] send_addr;
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2019-02-17 08:35:26 +01:00
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reg [19:0] local_pc;
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2019-02-17 12:05:38 +01:00
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reg [19:0] local_dp;
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2019-02-16 22:38:44 +01:00
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always @(posedge i_clk) begin
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2019-02-17 08:35:26 +01:00
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if (i_reset) begin
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2019-02-17 15:03:36 +01:00
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last_cmd <= 0;
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2019-02-16 22:38:44 +01:00
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o_stalled_by_bus <= 0;
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2019-02-17 08:35:26 +01:00
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o_bus_strobe <= 0;
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o_bus_cmd_data <= 1; // 1 is the default level
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2019-02-17 12:05:38 +01:00
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addr_cnt <= 0;
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2019-02-17 15:03:36 +01:00
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send_addr <= 0;
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2019-02-17 19:29:39 +01:00
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cmd_pc_read_s <= 0;
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2019-02-18 07:43:36 +01:00
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dp_read_s <= 0;
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2019-02-17 20:23:43 +01:00
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cmd_dp_write_s <= 0;
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cmd_load_dp_s <= 0;
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2019-02-17 19:29:39 +01:00
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cmd_config_s <= 0;
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cmd_reset_s <= 0;
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2019-02-17 08:35:26 +01:00
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end
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2019-02-16 22:38:44 +01:00
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2019-02-17 08:35:26 +01:00
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/*
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*
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* sending commands or data to the bus
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*
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*/
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2019-02-16 22:38:44 +01:00
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if (en_bus_send) begin
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2019-02-17 08:35:26 +01:00
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2019-02-17 19:29:39 +01:00
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/*
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* reset flags
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*/
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2019-02-18 07:43:36 +01:00
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if (do_cleanup) begin
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// $display("--------------------------------------------- BUS STATES CLEANUP");
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2019-02-17 20:23:43 +01:00
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cmd_pc_read_s <= 0;
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2019-02-18 07:43:36 +01:00
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dp_read_s <= 0;
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2019-02-17 20:23:43 +01:00
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cmd_dp_write_s <= 0;
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cmd_load_dp_s <= 0;
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2019-02-17 19:29:39 +01:00
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cmd_config_s <= 0;
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cmd_reset_s <= 0;
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end
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2019-02-17 20:23:43 +01:00
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/*
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* send the PC_READ command to restore the instruction flow
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* after a data transfer
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*/
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2019-02-17 21:20:18 +01:00
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if (do_cmd_pc_read) begin
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2019-02-17 20:23:43 +01:00
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$display("BUS_SEND %0d: [%d] PC_READ", `PH_BUS_SEND, i_cycle_ctr);
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o_bus_data <= `BUSCMD_PC_READ;
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last_cmd <= `BUSCMD_PC_READ;
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cmd_pc_read_s <= 1;
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o_bus_strobe <= 1;
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end
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|
if ((last_cmd == `BUSCMD_PC_READ) && !i_read_stall)
|
|
|
|
o_bus_strobe <= 1;
|
|
|
|
|
|
|
|
|
|
|
|
if (do_cmd_dp_write) begin
|
|
|
|
$display("BUS_SEND %0d: [%d] DP_WRITE", `PH_BUS_SEND, i_cycle_ctr);
|
|
|
|
o_bus_data <= `BUSCMD_DP_WRITE;
|
|
|
|
last_cmd <= `BUSCMD_DP_WRITE;
|
|
|
|
cmd_dp_write_s <= 1;
|
2019-02-17 23:05:33 +01:00
|
|
|
o_bus_strobe <= 1;
|
2019-02-17 20:23:43 +01:00
|
|
|
end
|
|
|
|
|
|
|
|
|
2019-02-17 12:05:38 +01:00
|
|
|
/*
|
|
|
|
* Sending LOAD_PC or LOAD_DP
|
|
|
|
*/
|
|
|
|
|
2019-02-16 22:38:44 +01:00
|
|
|
if (i_load_pc) begin
|
2019-02-17 12:05:38 +01:00
|
|
|
$display("BUS_SEND %0d: [%d] LOAD_PC %h", `PH_BUS_SEND, i_cycle_ctr, i_address);
|
2019-02-17 08:35:26 +01:00
|
|
|
o_bus_data <= `BUSCMD_LOAD_PC;
|
2019-02-17 12:05:38 +01:00
|
|
|
last_cmd <= `BUSCMD_LOAD_PC;
|
2019-02-17 08:35:26 +01:00
|
|
|
end
|
|
|
|
|
2019-02-17 20:23:43 +01:00
|
|
|
if (do_cmd_load_dp) begin
|
2019-02-17 12:05:38 +01:00
|
|
|
$display("BUS_SEND %0d: [%d] LOAD_DP %h", `PH_BUS_SEND, i_cycle_ctr, i_address);
|
2019-02-17 08:35:26 +01:00
|
|
|
o_bus_data <= `BUSCMD_LOAD_DP;
|
2019-02-17 12:05:38 +01:00
|
|
|
last_cmd <= `BUSCMD_LOAD_DP;
|
2019-02-17 20:23:43 +01:00
|
|
|
cmd_load_dp_s <= 1;
|
2019-02-17 08:35:26 +01:00
|
|
|
end
|
2019-02-16 22:38:44 +01:00
|
|
|
|
2019-02-17 19:29:39 +01:00
|
|
|
if (do_cmd_config) begin
|
|
|
|
$display("BUS_SEND %0d: [%d] CONFIGURE %h", `PH_BUS_SEND, i_cycle_ctr, i_address);
|
|
|
|
o_bus_data <= `BUSCMD_CONFIGURE;
|
|
|
|
last_cmd <= `BUSCMD_CONFIGURE;
|
|
|
|
cmd_config_s <= 1;
|
|
|
|
end
|
|
|
|
|
|
|
|
if (do_cmd_reset) begin
|
|
|
|
$display("BUS_SEND %0d: [%d] RESET", `PH_BUS_SEND, i_cycle_ctr);
|
|
|
|
o_bus_data <= `BUSCMD_RESET;
|
|
|
|
last_cmd <= `BUSCMD_RESET;
|
|
|
|
cmd_reset_s <= 1;
|
|
|
|
o_bus_strobe <= 1;
|
|
|
|
end
|
|
|
|
|
|
|
|
// configure loop to send i_address to the bus
|
|
|
|
// used for LOAD_PC, LOAD_DP, CONFIGURE,
|
2019-02-17 20:23:43 +01:00
|
|
|
if (i_load_pc || do_cmd_load_dp || do_cmd_config) begin
|
2019-02-16 22:38:44 +01:00
|
|
|
o_stalled_by_bus <= 1;
|
2019-02-17 12:05:38 +01:00
|
|
|
o_bus_cmd_data <= 0;
|
|
|
|
addr_cnt <= 0;
|
|
|
|
send_addr <= 1;
|
|
|
|
o_bus_strobe <= 1;
|
2019-02-16 22:38:44 +01:00
|
|
|
end
|
2019-02-17 08:35:26 +01:00
|
|
|
|
2019-02-17 12:05:38 +01:00
|
|
|
// sending address bits
|
2019-02-17 08:35:26 +01:00
|
|
|
if (send_addr) begin
|
2019-02-18 11:36:28 +01:00
|
|
|
`ifdef SIM
|
2019-02-17 12:05:38 +01:00
|
|
|
$display("BUS_SEND %0d: [%d] addr[%0d] %h =>",
|
|
|
|
`PH_BUS_SEND, i_cycle_ctr, addr_cnt, i_address[addr_cnt*4+:4]);
|
2019-02-18 11:36:28 +01:00
|
|
|
`endif
|
2019-02-17 08:35:26 +01:00
|
|
|
o_bus_data <= i_address[addr_cnt*4+:4];
|
|
|
|
addr_cnt <= addr_cnt + 1;
|
2019-02-17 12:05:38 +01:00
|
|
|
o_bus_strobe <= 1;
|
2019-02-17 08:35:26 +01:00
|
|
|
end
|
|
|
|
|
2019-02-18 07:43:36 +01:00
|
|
|
/*
|
|
|
|
* nothing to do for reading data
|
|
|
|
*/
|
|
|
|
|
2019-02-17 12:05:38 +01:00
|
|
|
/*
|
|
|
|
* writing data to the bus,
|
|
|
|
* send DP_WRITE first if necessary
|
|
|
|
*/
|
|
|
|
|
2019-02-17 21:20:18 +01:00
|
|
|
if (do_dp_write_data) begin
|
2019-02-18 07:43:36 +01:00
|
|
|
if (last_cmd == `BUSCMD_DP_WRITE) begin
|
2019-02-17 12:05:38 +01:00
|
|
|
$display("BUS_SEND %0d: [%d] WRITE %h =>", `PH_BUS_SEND, i_cycle_ctr, i_nibble);
|
|
|
|
o_bus_data <= i_nibble;
|
2019-02-17 08:35:26 +01:00
|
|
|
o_bus_strobe <= 1;
|
2019-02-17 12:05:38 +01:00
|
|
|
end
|
|
|
|
end
|
|
|
|
|
2019-02-17 19:29:39 +01:00
|
|
|
end
|
2019-02-17 12:05:38 +01:00
|
|
|
|
2019-02-16 22:38:44 +01:00
|
|
|
|
2019-02-17 08:35:26 +01:00
|
|
|
/*
|
|
|
|
*
|
|
|
|
* reading data from the bus
|
|
|
|
*
|
|
|
|
*/
|
2019-02-17 12:05:38 +01:00
|
|
|
|
2019-02-18 11:36:28 +01:00
|
|
|
if (do_read_from_bus) begin
|
|
|
|
`ifdef SIM
|
|
|
|
$display("BUS_RECV %0d: [%d] <= READ(%s) [%5h] %h",
|
|
|
|
`PH_BUS_RECV, i_cycle_ctr, use_pc_as_pointer?"PC":"DP",
|
|
|
|
read_pointer, rom[read_pointer]);
|
|
|
|
`endif
|
|
|
|
o_nibble <= rom[read_pointer];
|
|
|
|
if (use_pc_as_pointer) local_pc <= local_pc + 1;
|
|
|
|
else begin
|
|
|
|
local_dp <= local_dp + 1;
|
|
|
|
dp_read_s <= 1;
|
|
|
|
end
|
|
|
|
end
|
|
|
|
|
|
|
|
if (do_display_stalled) begin
|
2019-02-17 21:20:18 +01:00
|
|
|
$display("BUS_RECV %0d: [%d] STALLED", `PH_BUS_RECV, i_cycle_ctr);
|
2019-02-18 11:36:28 +01:00
|
|
|
end
|
2019-02-16 22:38:44 +01:00
|
|
|
|
2019-02-17 08:35:26 +01:00
|
|
|
/*
|
|
|
|
*
|
|
|
|
* resets the bus automatically
|
|
|
|
*
|
|
|
|
*/
|
2019-02-18 11:36:28 +01:00
|
|
|
if (en_bus_recv) begin
|
2019-02-16 22:38:44 +01:00
|
|
|
o_bus_strobe <= 0;
|
2019-02-17 08:35:26 +01:00
|
|
|
o_bus_cmd_data <= 1;
|
2019-02-17 15:03:36 +01:00
|
|
|
end
|
|
|
|
|
2019-02-18 11:36:28 +01:00
|
|
|
|
2019-02-17 19:29:39 +01:00
|
|
|
if (en_bus_ecmd) begin
|
2019-02-17 20:23:43 +01:00
|
|
|
|
|
|
|
// stalling and unstalling stuff
|
|
|
|
|
2019-02-18 07:43:36 +01:00
|
|
|
if (do_dp_read_data_sc || cmd_reset_sc || cmd_config_sc) begin
|
|
|
|
// $display("-------------------------------------- STALL");
|
2019-02-17 19:29:39 +01:00
|
|
|
o_stalled_by_bus <= 1;
|
|
|
|
end
|
|
|
|
|
2019-02-17 20:23:43 +01:00
|
|
|
if (do_unstall) begin
|
2019-02-18 07:43:36 +01:00
|
|
|
// $display("-------------------------------------- NO - STALL");
|
2019-02-17 19:29:39 +01:00
|
|
|
o_stalled_by_bus <= 0;
|
|
|
|
addr_cnt <= 0;
|
|
|
|
end
|
|
|
|
|
|
|
|
if (addr_s) begin
|
|
|
|
send_addr <= 0;
|
|
|
|
end
|
|
|
|
|
2019-02-17 15:03:36 +01:00
|
|
|
// command automatic switchover
|
|
|
|
|
|
|
|
case (last_cmd)
|
2019-02-18 11:36:28 +01:00
|
|
|
`BUSCMD_NOP: begin end
|
2019-02-17 15:03:36 +01:00
|
|
|
`BUSCMD_LOAD_PC,
|
|
|
|
`BUSCMD_LOAD_DP:
|
2019-02-18 11:36:28 +01:00
|
|
|
if (send_addr && addr_s) begin
|
2019-02-17 19:29:39 +01:00
|
|
|
// reset the addr count for next time
|
|
|
|
$display("BUS_ECMD %0d: [%d] <= %s_READ mode",
|
2019-02-17 15:03:36 +01:00
|
|
|
`PH_BUS_ECMD, i_cycle_ctr,
|
2019-02-17 19:29:39 +01:00
|
|
|
(last_cmd == `BUSCMD_LOAD_PC)?"PC":"DP");
|
2019-02-17 15:03:36 +01:00
|
|
|
last_cmd <= (last_cmd == `BUSCMD_LOAD_PC)?`BUSCMD_PC_READ:`BUSCMD_DP_READ;
|
|
|
|
case (last_cmd)
|
|
|
|
`BUSCMD_LOAD_PC: local_pc <= i_address;
|
|
|
|
`BUSCMD_LOAD_DP: local_dp <= i_address;
|
|
|
|
endcase
|
|
|
|
send_addr <= 0;
|
2019-02-18 07:43:36 +01:00
|
|
|
if (!do_dp_read_data) begin
|
|
|
|
// $display("-------------------------------------- NO - STALL (auto-change mode)");
|
|
|
|
o_stalled_by_bus <= 0;
|
|
|
|
end
|
2019-02-17 15:03:36 +01:00
|
|
|
end
|
2019-02-17 19:29:39 +01:00
|
|
|
`BUSCMD_PC_READ: begin end
|
2019-02-18 07:43:36 +01:00
|
|
|
`BUSCMD_DP_READ: begin end
|
2019-02-17 20:23:43 +01:00
|
|
|
`BUSCMD_DP_WRITE: begin end
|
2019-02-17 19:29:39 +01:00
|
|
|
`BUSCMD_CONFIGURE: begin end
|
|
|
|
`BUSCMD_RESET: begin end
|
|
|
|
default: $display("------------ UNHANDLED BUSCMD %h", last_cmd);
|
2019-02-17 15:03:36 +01:00
|
|
|
endcase
|
|
|
|
|
|
|
|
|
|
|
|
|
2019-02-17 08:35:26 +01:00
|
|
|
end
|
|
|
|
|
2019-02-17 15:03:36 +01:00
|
|
|
|
2019-02-16 22:38:44 +01:00
|
|
|
end
|
|
|
|
|
|
|
|
endmodule
|
|
|
|
|
|
|
|
`endif
|