CAN总线控制器IP核代码分析

include timescale.v

// synopsys translate_on

`include can_defines.v

module can_top

(

`ifdef CAN_WISHBONE_IF

wb_clk_i,

wb_rst_i,

wb_dat_i,

wb_dat_o,

wb_cyc_i,

wb_stb_i,

wb_we_i,

wb_adr_i,

wb_ack_o,

`else

rst_i,

ale_i,

rd_i,

wr_i,

port_0_io,

`endif

cs_can_i,

clk_i,

rx_i,

tx_o,

irq_on,

clkout_o

);

parameter Tp = 1;

`ifdef CAN_WISHBONE_IF

input wb_clk_i;

input wb_rst_i;

input [7:0] wb_dat_i;

output [7:0] wb_dat_o;

input wb_cyc_i;

input wb_stb_i;

input wb_we_i;

input [7:0] wb_adr_i;

output wb_ack_o;

reg wb_ack_o;

reg cs_sync1;

reg cs_sync2;

reg cs_sync3;

reg cs_ack1;

reg cs_ack2;

reg cs_ack3;

reg cs_sync_rst1;

reg cs_sync_rst2;

`else

input rst_i;

input ale_i;

input rd_i;

input wr_i;

inout [7:0] port_0_io;

reg [7:0] addr_latched;

reg wr_i_q;

reg rd_i_q;

`endif

input cs_can_i;

input clk_i;

input rx_i;

output tx_o;

output irq_on;

output clkout_o;

reg data_out_fifo_selected;

wire irq_o;

wire [7:0] data_out_fifo;

wire [7:0] data_out_regs;

/* Mode register */

wire reset_mode;

wire listen_only_mode;

wire acceptance_filter_mode;

wire self_test_mode;

/* Command register */

wire release_buffer;

wire tx_request;

wire abort_tx;

wire self_rx_request;

wire single_shot_transmission;

/* Arbitration Lost Capture Register */

wire read_arbitration_lost_capture_reg;

/* Error Code Capture Register */

wire read_error_code_capture_reg;

wire [7:0] error_capture_code;

/* Bus Timing 0 register */

wire [5:0] baud_r_presc;

wire [1:0] sync_jump_width;

/* Bus Timing 1 register */

wire [3:0] time_segment1;

wire [2:0] time_segment2;

wire triple_sampling;

/* Error Warning Limit register */

wire [7:0] error_warning_limit;

/* Rx Error Counter register */

wire we_rx_err_cnt;

/* Tx Error Counter register */

wire we_tx_err_cnt;

/* Clock Divider register */

wire extended_mode;

/* This section is for BASIC and EXTENDED mode */

/* Acceptance code register */

wire [7:0] acceptance_code_0;

/* Acceptance mask register */

wire [7:0] acceptance_mask_0;

/* End: This section is for BASIC and EXTENDED mode */

/* This section is for EXTENDED mode */

/* Acceptance code register */

wire [7:0] acceptance_code_1;

wire [7:0] acceptance_code_2;

wire [7:0] acceptance_code_3;

/* Acceptance mask register */

wire [7:0] acceptance_mask_1;

wire [7:0] acceptance_mask_2;

wire [7:0] acceptance_mask_3;

/* End: This section is for EXTENDED mode */

/* Tx data registers. Holding identifier (basic mode), tx frame information (extended mode) and data */

wire [7:0] tx_data_0;

wire [7:0] tx_data_1;

wire [7:0] tx_data_2;

wire [7:0] tx_data_3;

wire [7:0] tx_data_4;

wire [7:0] tx_data_5;

wire [7:0] tx_data_6;

wire [7:0] tx_data_7;

wire [7:0] tx_data_8;

wire [7:0] tx_data_9;

wire [7:0] tx_data_10;

wire [7:0] tx_data_11;

wire [7:0] tx_data_12;

/* End: Tx data registers */

wire cs;

/* Output signals from can_btl module */

wire clk_en;

wire sample_point;

wire sampled_bit;

wire sampled_bit_q;

wire tx_point;

wire hard_sync;

wire resync;

/* output from can_bsp module */

wire rx_idle;

wire transmitting;

wire last_bit_of_inter;

wire set_reset_mode;

wire node_bus_off;

wire error_status;

wire [7:0] rx_err_cnt;

wire [7:0] tx_err_cnt;

wire rx_err_cnt_dummy; // The MSB is not displayed. It is just used for easier calculation (no counter overflow).

wire tx_err_cnt_dummy; // The MSB is not displayed. It is just used for easier calculation (no counter overflow).

wire transmit_status;

wire receive_status;

wire tx_successful;

wire need_to_tx;

wire overrun;

wire info_empty;

wire set_bus_error_irq;

wire set_arbitration_lost_irq;

wire [4:0] arbitration_lost_capture;

wire node_error_passive;

wire node_error_active;

wire [6:0] rx_message_counter;

wire tx_out;

wire tx_oen;

wire rst;

wire we;

wire [7:0] addr;

wire [7:0] data_in;

reg [7:0] data_out;