CAN总线控制器IP核代码分析

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;

/* Connecting can_registers module */

can_registers i_can_registers

(

.clk(clk_i),

.rst(rst),

.cs(cs),

.we(we),

.addr(addr),

.data_in(data_in),

.data_out(data_out_regs),

.irq(irq_o),

.sample_point(sample_point),

.transmitting(transmitting),

.set_reset_mode(set_reset_mode),

.node_bus_off(node_bus_off),

.error_status(error_status),

.rx_err_cnt(rx_err_cnt),

.tx_err_cnt(tx_err_cnt),

.transmit_status(transmit_status),

.receive_status(receive_status),

.tx_successful(tx_successful),

.need_to_tx(need_to_tx),

.overrun(overrun),

.info_empty(info_empty),

.set_bus_error_irq(set_bus_error_irq),

.set_arbitration_lost_irq(set_arbitration_lost_irq),

.arbitration_lost_capture(arbitration_lost_capture),

.node_error_passive(node_error_passive),

.node_error_active(node_error_active),

.rx_message_counter(rx_message_counter),

/* Mode register */

.reset_mode(reset_mode),

.listen_only_mode(listen_only_mode),

.acceptance_filter_mode(acceptance_filter_mode),

.self_test_mode(self_test_mode),

/* Command register */

.clear_data_overrun(),

.release_buffer(release_buffer),

.abort_tx(abort_tx),

.tx_request(tx_request),

.self_rx_request(self_rx_request),

.single_shot_transmission(single_shot_transmission),

/* Arbitration Lost Capture Register */

.read_arbitration_lost_capture_reg(read_arbitration_lost_capture_reg),

/* Error Code Capture Register */

.read_error_code_capture_reg(read_error_code_capture_reg),

.error_capture_code(error_capture_code),

/* Bus Timing 0 register */

.baud_r_presc(baud_r_presc),

.sync_jump_width(sync_jump_width),

/* Bus Timing 1 register */

.time_segment1(time_segment1),

.time_segment2(time_segment2),

.triple_sampling(triple_sampling),

/* Error Warning Limit register */

.error_warning_limit(error_warning_limit),

/* Rx Error Counter register */

.we_rx_err_cnt(we_rx_err_cnt),

/* Tx Error Counter register */

.we_tx_err_cnt(we_tx_err_cnt),

/* Clock Divider register */

.extended_mode(extended_mode),

.clkout(clkout_o),

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

/* Acceptance code register */

.acceptance_code_0(acceptance_code_0),

/* Acceptance mask register */

.acceptance_mask_0(acceptance_mask_0),

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

/* This section is for EXTENDED mode */

/* Acceptance code register */

.acceptance_code_1(acceptance_code_1),

.acceptance_code_2(acceptance_code_2),

.acceptance_code_3(acceptance_code_3),

/* Acceptance mask register */

.acceptance_mask_1(acceptance_mask_1),

.acceptance_mask_2(acceptance_mask_2),

.acceptance_mask_3(acceptance_mask_3),

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

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

.tx_data_0(tx_data_0),

.tx_data_1(tx_data_1),

.tx_data_2(tx_data_2),

.tx_data_3(tx_data_3),

.tx_data_4(tx_data_4),

.tx_data_5(tx_data_5),

.tx_data_6(tx_data_6),

.tx_data_7(tx_data_7),

.tx_data_8(tx_data_8),

.tx_data_9(tx_data_9),

.tx_data_10(tx_data_10),

.tx_data_11(tx_data_11),

.tx_data_12(tx_data_12)

/* End: Tx data registers */

);

assign irq_on = ~irq_o;

/* Connecting can_btl module */

can_btl i_can_btl

(

.clk(clk_i),

.rst(rst),

.rx(rx_i),

/* Mode register */

.reset_mode(reset_mode),

/* Bus Timing 0 register */

.baud_r_presc(baud_r_presc),

.sync_jump_width(sync_jump_width),

/* Bus Timing 1 register */

.time_segment1(time_segment1),

.time_segment2(time_segment2),

.triple_sampling(triple_sampling),

/* Output signals from this module */

.clk_en(clk_en),

.sample_point(sample_point),

.sampled_bit(sampled_bit),

.sampled_bit_q(sampled_bit_q),

.tx_point(tx_point),

.hard_sync(hard_sync),

.resync(resync),

/* output from can_bsp module */

.rx_idle(rx_idle),

.transmitting(transmitting),

.last_bit_of_inter(last_bit_of_inter)

);

can_bsp i_can_bsp

(

.clk(clk_i),

.rst(rst),

/* From btl module */

.sample_point(sample_point),

.sampled_bit(sampled_bit),

.sampled_bit_q(sampled_bit_q),

.tx_point(tx_point),

.hard_sync(hard_sync),

.addr(addr),

.data_in(data_in),

.data_out(data_out_fifo),

.fifo_selected(data_out_fifo_selected),