目录
- 日常·唠嗑
- 一、程序设计
- 二、镁光模型仿真验证
- 三、testbench文件
- 四、完整工程下载
日常·唠嗑
IIC协议这里就不赘述了，网上很多，这里推荐两个，可以看看【接口时序】6、IIC总线的原理与Verilog实现 ，还有IIC协议原理以及主机、从机Verilog实现。
前者是对IIC协议详细介绍、以及主机发送，主机接收两种方式。后者，是在前者基础上做设计，讲的是主机、从机两种设计实例。关于IIC从机，网上例程较少，可以参考这个博主的。不过，这个博主的状态机写的很乱，也没什么注释，看了两天才搞明白Verilog描述的什么，如果有FPGA爱好者需要用到，又看不懂的，可以私信我：bumianzhe@126.com.
一、程序设计
本程序参考芯路恒IIC设计，可以去他们官网下完整资料看看。
顶层模块：用来控制底层模块连续读写，包含了状态机
module i2c_control(Clk,Rst_n,wrreg_req,rdreg_req,addr,addr_mode,wrdata,rddata,device_id,RW_Done,ack,i2c_sclk,i2c_sdat
);input Clk;input Rst_n;input wrreg_req;input rdreg_req;input [15:0]addr;input addr_mode;input [7:0]wrdata;output reg[7:0]rddata;input [7:0]device_id;output reg RW_Done;output reg ack;output i2c_sclk;inout i2c_sdat;reg [5:0]Cmd;reg [7:0]Tx_DATA;wire Trans_Done;wire ack_o;reg Go;wire [15:0] reg_addr;assign reg_addr = addr_mode?addr:{addr[7:0],addr[15:8]};wire [7:0]Rx_DATA;localparam WR = 6'b000001, //写请求STA = 6'b000010, //起始位请求RD = 6'b000100, //读请求STO = 6'b001000, //停止位请求ACK = 6'b010000, //应答位请求NACK = 6'b100000; //无应答请求i2c_bit_shift i2c_bit_shift(.Clk(Clk),.Rst_n(Rst_n),.Cmd(Cmd),.Go(Go),.Rx_DATA(Rx_DATA),.Tx_DATA(Tx_DATA),.Trans_Done(Trans_Done),.ack_o(ack_o),.i2c_sclk(i2c_sclk),.i2c_sdat(i2c_sdat));reg [6:0]state;reg [7:0]cnt;localparamIDLE = 7'b0000001, //空闲状态WR_REG = 7'b0000010, //写寄存器状态WAIT_WR_DONE = 7'b0000100, //等待写寄存器完成状态WR_REG_DONE = 7'b0001000, //写寄存器完成状态RD_REG = 7'b0010000, //读寄存器状态WAIT_RD_DONE = 7'b0100000, //等待读寄存器完成状态RD_REG_DONE = 7'b1000000; //读寄存器完成状态always@(posedge Clk or negedge Rst_n)if(!Rst_n)beginCmd <= 6'd0;Tx_DATA <= 8'd0;Go <= 1'b0;rddata <= 0;state <= IDLE;ack <= 0;endelse begincase(state)IDLE:begincnt <= 0;ack <= 0;RW_Done <= 1'b0; if(wrreg_req)state <= WR_REG;else if(rdreg_req)state <= RD_REG;elsestate <= IDLE;endWR_REG:beginstate <= WAIT_WR_DONE;case(cnt)0:write_byte(WR | STA, device_id);1:write_byte(WR, reg_addr[15:8]);2:write_byte(WR, reg_addr[7:0]);3:write_byte(WR | STO, wrdata);default:;endcaseendWAIT_WR_DONE:beginGo <= 1'b0; if(Trans_Done)beginack <= ack | ack_o;case(cnt)0: begin cnt <= 1; state <= WR_REG;end1: begin state <= WR_REG;if(addr_mode)cnt <= 2; elsecnt <= 3;end2: begincnt <= 3;state <= WR_REG;end3:state <= WR_REG_DONE;default:state <= IDLE;endcaseendendWR_REG_DONE:beginRW_Done <= 1'b1;state <= IDLE;endRD_REG:beginstate <= WAIT_RD_DONE;case(cnt)0:write_byte(WR | STA, device_id);1:write_byte(WR, reg_addr[15:8]);2:write_byte(WR, reg_addr[7:0]);3:write_byte(WR | STA, device_id | 8'd1);4:read_byte(RD | NACK | STO);default:;endcaseendWAIT_RD_DONE:beginGo <= 1'b0; if(Trans_Done)beginif(cnt <= 3)ack <= ack | ack_o;case(cnt)0: begin cnt <= 1; state <= RD_REG;end1: begin state <= RD_REG;if(addr_mode)cnt <= 2; elsecnt <= 3;end2: begincnt <= 3;state <= RD_REG;end3:begincnt <= 4;state <= RD_REG;end4:state <= RD_REG_DONE;default:state <= IDLE;endcaseendendRD_REG_DONE:beginRW_Done <= 1'b1;rddata <= Rx_DATA;state <= IDLE; enddefault:state <= IDLE;endcaseendtask read_byte;input [5:0]Ctrl_Cmd;beginCmd <= Ctrl_Cmd;Go <= 1'b1; endendtasktask write_byte;input [5:0]Ctrl_Cmd;input [7:0]Wr_Byte_Data;beginCmd <= Ctrl_Cmd;Tx_DATA <= Wr_Byte_Data;Go <= 1'b1; endendtaskendmodule子模块：单字节读写操作
module i2c_bit_shift(Clk,Rst_n,Cmd,Go,Rx_DATA,Tx_DATA,Trans_Done,ack_o,i2c_sclk,i2c_sdat
);input Clk;input Rst_n;input [5:0]Cmd;input Go;output reg[7:0]Rx_DATA;input [7:0]Tx_DATA;output reg Trans_Done;output reg ack_o;output reg i2c_sclk;inout i2c_sdat;reg i2c_sdat_o;//系统时钟采用50MHzparameter SYS_CLOCK = 50_000_000;//SCL总线时钟采用400kHzparameter SCL_CLOCK = 400_000;//产生时钟SCL计数器最大值localparam SCL_CNT_M = SYS_CLOCK/SCL_CLOCK/4 - 1;reg i2c_sdat_oe;localparam WR = 6'b000001, //写请求STA = 6'b000010, //起始位请求RD = 6'b000100, //读请求STO = 6'b001000, //停止位请求ACK = 6'b010000, //应答位请求NACK = 6'b100000; //无应答请求reg [19:0]div_cnt;reg en_div_cnt;always@(posedge Clk or negedge Rst_n)if(!Rst_n)div_cnt <= 20'd0;else if(en_div_cnt)beginif(div_cnt < SCL_CNT_M)div_cnt <= div_cnt + 1'b1;elsediv_cnt <= 0;endelsediv_cnt <= 0;wire sclk_plus = div_cnt == SCL_CNT_M;//assign i2c_sdat = i2c_sdat_oe?i2c_sdat_o:1'bz;assign i2c_sdat = !i2c_sdat_o && i2c_sdat_oe ? 1'b0:1'bz;reg [7:0]state;localparamIDLE = 8'b00000001, //空闲状态GEN_STA = 8'b00000010, //产生起始信号WR_DATA = 8'b00000100, //写数据状态RD_DATA = 8'b00001000, //读数据状态CHECK_ACK = 8'b00010000, //检测应答状态GEN_ACK = 8'b00100000, //产生应答状态GEN_STO = 8'b01000000; //产生停止信号reg [4:0]cnt;always@(posedge Clk or negedge Rst_n)if(!Rst_n)beginRx_DATA <= 0;i2c_sdat_oe <= 1'd0;en_div_cnt <= 1'b0;i2c_sdat_o <= 1'd1;Trans_Done <= 1'b0;ack_o <= 0;state <= IDLE;cnt <= 0;endelse begincase(state)IDLE:beginTrans_Done <= 1'b0;i2c_sdat_oe <= 1'd1;if(Go)beginen_div_cnt <= 1'b1;if(Cmd & STA)state <= GEN_STA;else if(Cmd & WR)state <= WR_DATA;else if(Cmd & RD)state <= RD_DATA;elsestate <= IDLE;endelse beginen_div_cnt <= 1'b0;state <= IDLE;endendGEN_STA:beginif(sclk_plus)beginif(cnt == 3)cnt <= 0;elsecnt <= cnt + 1'b1;case(cnt)0:begin i2c_sdat_o <= 1; i2c_sdat_oe <= 1'd1;end1:begin i2c_sclk <= 1;end2:begin i2c_sdat_o <= 0; i2c_sclk <= 1;end3:begin i2c_sclk <= 0;enddefault:begin i2c_sdat_o <= 1; i2c_sclk <= 1;endendcaseif(cnt == 3)beginif(Cmd & WR)state <= WR_DATA;else if(Cmd & RD)state <= RD_DATA;endendendWR_DATA:beginif(sclk_plus)beginif(cnt == 31)cnt <= 0;elsecnt <= cnt + 1'b1;case(cnt)0,4,8,12,16,20,24,28:begin i2c_sdat_o <= Tx_DATA[7-cnt[4:2]]; i2c_sdat_oe <= 1'd1;end //set data;1,5,9,13,17,21,25,29:begin i2c_sclk <= 1;end //sclk posedge2,6,10,14,18,22,26,30:begin i2c_sclk <= 1;end //sclk keep high3,7,11,15,19,23,27,31:begin i2c_sclk <= 0;end //sclk negedge
/* 0 :begin i2c_sdat_o <= Tx_DATA[7];end1 :begin i2c_sclk <= 1;end //sclk posedge2 :begin i2c_sclk <= 1;end //sclk keep high3 :begin i2c_sclk <= 0;end //sclk negedge4 :begin i2c_sdat_o <= Tx_DATA[6];end5 :begin i2c_sclk <= 1;end //sclk posedge6 :begin i2c_sclk <= 1;end //sclk keep high7 :begin i2c_sclk <= 0;end //sclk negedge8 :begin i2c_sdat_o <= Tx_DATA[5];end9 :begin i2c_sclk <= 1;end //sclk posedge10:begin i2c_sclk <= 1;end //sclk keep high11:begin i2c_sclk <= 0;end //sclk negedge12:begin i2c_sdat_o <= Tx_DATA[4];end13:begin i2c_sclk <= 1;end //sclk posedge14:begin i2c_sclk <= 1;end //sclk keep high15:begin i2c_sclk <= 0;end //sclk negedge16:begin i2c_sdat_o <= Tx_DATA[3];end17:begin i2c_sclk <= 1;end //sclk posedge18:begin i2c_sclk <= 1;end //sclk keep high19:begin i2c_sclk <= 0;end //sclk negedge20:begin i2c_sdat_o <= Tx_DATA[2];end21:begin i2c_sclk <= 1;end //sclk posedge22:begin i2c_sclk <= 1;end //sclk keep high23:begin i2c_sclk <= 0;end //sclk negedge 24:begin i2c_sdat_o <= Tx_DATA[1];end25:begin i2c_sclk <= 1;end //sclk posedge26:begin i2c_sclk <= 1;end //sclk keep high27:begin i2c_sclk <= 0;end //sclk negedge 28:begin i2c_sdat_o <= Tx_DATA[0];end29:begin i2c_sclk <= 1;end //sclk posedge30:begin i2c_sclk <= 1;end //sclk keep high31:begin i2c_sclk <= 0;end //sclk negedge
*/ default:begin i2c_sdat_o <= 1; i2c_sclk <= 1;endendcaseif(cnt == 31)beginstate <= CHECK_ACK;endendendRD_DATA:beginif(sclk_plus)beginif(cnt == 31)cnt <= 0;elsecnt <= cnt + 1'b1;case(cnt)0,4,8,12,16,20,24,28:begin i2c_sdat_oe <= 1'd0; i2c_sclk <= 0;end //set data;1,5,9,13,17,21,25,29:begin i2c_sclk <= 1;end //sclk posedge2,6,10,14,18,22,26,30:begin i2c_sclk <= 1; Rx_DATA <= {Rx_DATA[6:0],i2c_sdat};end //sclk keep high3,7,11,15,19,23,27,31:begin i2c_sclk <= 0;end //sclk negedge default:begin i2c_sdat_o <= 1; i2c_sclk <= 1;endendcaseif(cnt == 31)beginstate <= GEN_ACK;endendendCHECK_ACK:beginif(sclk_plus)beginif(cnt == 3)cnt <= 0;elsecnt <= cnt + 1'b1;case(cnt)0:begin i2c_sdat_oe <= 1'd0; i2c_sclk <= 0;end1:begin i2c_sclk <= 1;end2:begin ack_o <= i2c_sdat; i2c_sclk <= 1;end3:begin i2c_sclk <= 0;enddefault:begin i2c_sdat_o <= 1; i2c_sclk <= 1;endendcaseif(cnt == 3)beginif(Cmd & STO)state <= GEN_STO;else beginstate <= IDLE;Trans_Done <= 1'b1;end endendendGEN_ACK:beginif(sclk_plus)beginif(cnt == 3)cnt <= 0;elsecnt <= cnt + 1'b1;case(cnt)0:begin i2c_sdat_oe <= 1'd1;i2c_sclk <= 0;if(Cmd & ACK)i2c_sdat_o <= 1'b0;else if(Cmd & NACK)i2c_sdat_o <= 1'b1;end1:begin i2c_sclk <= 1;end2:begin i2c_sclk <= 1;end3:begin i2c_sclk <= 0;enddefault:begin i2c_sdat_o <= 1; i2c_sclk <= 1;endendcaseif(cnt == 3)beginif(Cmd & STO)state <= GEN_STO;else beginstate <= IDLE;Trans_Done <= 1'b1;endendendendGEN_STO:beginif(sclk_plus)beginif(cnt == 3)cnt <= 0;elsecnt <= cnt + 1'b1;case(cnt)0:begin i2c_sdat_o <= 0; i2c_sdat_oe <= 1'd1;end1:begin i2c_sclk <= 1;end2:begin i2c_sdat_o <= 1; i2c_sclk <= 1;end3:begin i2c_sclk <= 1;enddefault:begin i2c_sdat_o <= 1; i2c_sclk <= 1;endendcaseif(cnt == 3)beginTrans_Done <= 1'b1;state <= IDLE;endendenddefault:state <= IDLE;endcaseendendmodule二、镁光模型仿真验证
镁 光 官 网 提 供 的 EEPROM 仿 真 模 型 ， 具 体 下 载 网 址 为 ：
http://ww1.microchip.com/downloads/en/DeviceDoc/24xx04_Verilog_Model.zip
1、本次使用的是1 字节寄存器地址段的 24LC04B 仿真模型，进行验证
// *******************************************************************************************************
// ** **
// ** 24LC04B.v - Microchip 24LC04B 4K-BIT I2C SERIAL EEPROM (VCC = +2.5V TO +5.5V) **
// ** **
// *******************************************************************************************************
// ** **
// ** This information is distributed under license from Young Engineering. **
// ** COPYRIGHT (c) 2003 YOUNG ENGINEERING **
// ** ALL RIGHTS RESERVED **
// ** **
// ** **
// ** Young Engineering provides design expertise for the digital world **
// ** Started in 1990, Young Engineering offers products and services for your electronic design **
// ** project. We have the expertise in PCB, FPGA, ASIC, firmware, and software design. **
// ** From concept to prototype to production, we can help you. **
// ** **
// ** http://www.young-engineering.com/ **
// ** **
// *******************************************************************************************************
// ** This information is provided to you for your convenience and use with Microchip products only. **
// ** Microchip disclaims all liability arising from this information and its use. **
// ** **
// ** THIS INFORMATION IS PROVIDED "AS IS." MICROCHIP MAKES NO REPRESENTATION OR WARRANTIES OF **
// ** ANY KIND WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, STATUTORY OR OTHERWISE, RELATED TO **
// ** THE INFORMATION PROVIDED TO YOU, INCLUDING BUT NOT LIMITED TO ITS CONDITION, QUALITY, **
// ** PERFORMANCE, MERCHANTABILITY, NON-INFRINGEMENT, OR FITNESS FOR PURPOSE. **
// ** MICROCHIP IS NOT LIABLE, UNDER ANY CIRCUMSTANCES, FOR SPECIAL, INCIDENTAL OR CONSEQUENTIAL **
// ** DAMAGES, FOR ANY REASON WHATSOEVER. **
// ** **
// ** It is your responsibility to ensure that your application meets with your specifications. **
// ** **
// *******************************************************************************************************
// ** Revision : 1.3 **
// ** Modified Date : 12/04/2006 **
// ** Revision History: **
// ** **
// ** 02/01/2003: Initial design **
// ** 07/19/2004: Fixed the timing checks and the open-drain modeling for SDA. **
// ** 01/06/2006: Changed the legal information in the header **
// ** 12/04/2006: Corrected timing checks to reference proper clock edges **
// ** Added timing check for Tbuf (bus free time) **
// ** **
// *******************************************************************************************************
// ** TABLE OF CONTENTS **
// *******************************************************************************************************
// **---------------------------------------------------------------------------------------------------**
// ** DECLARATIONS **
// **---------------------------------------------------------------------------------------------------**
// **---------------------------------------------------------------------------------------------------**
// ** INITIALIZATION **
// **---------------------------------------------------------------------------------------------------**
// **---------------------------------------------------------------------------------------------------**
// ** CORE LOGIC **
// **---------------------------------------------------------------------------------------------------**
// ** 1.01: START Bit Detection **
// ** 1.02: STOP Bit Detection **
// ** 1.03: Input Shift Register **
// ** 1.04: Input Bit Counter **
// ** 1.05: Control Byte Register **
// ** 1.06: Byte Address Register **
// ** 1.07: Write Data Buffer **
// ** 1.08: Acknowledge Generator **
// ** 1.09: Acknowledge Detect **
// ** 1.10: Write Cycle Timer **
// ** 1.11: Write Cycle Processor **
// ** 1.12: Read Data Multiplexor **
// ** 1.13: Read Data Processor **
// ** 1.14: SDA Data I/O Buffer **
// ** **
// **---------------------------------------------------------------------------------------------------**
// ** DEBUG LOGIC **
// **---------------------------------------------------------------------------------------------------**
// ** 2.01: Memory Data Bytes **
// ** 2.02: Write Data Buffer **
// ** **
// **---------------------------------------------------------------------------------------------------**
// ** TIMING CHECKS **
// **---------------------------------------------------------------------------------------------------**
// ** **
// *******************************************************************************************************`timescale 1ns/10psmodule M24LC04B (A0, A1, A2, WP, SDA, SCL, RESET);input A0; // unconnected pininput A1; // unconnected pininput A2; // unconnected pininput WP; // write protect pininout SDA; // serial data I/Oinput SCL; // serial data clockinput RESET; // system reset// *******************************************************************************************************
// ** DECLARATIONS **
// *******************************************************************************************************reg SDA_DO; // serial data - outputreg SDA_OE; // serial data - output enablewire SDA_DriveEnable; // serial data output enablereg SDA_DriveEnableDlyd; // serial data output enable - delayedwire [02:00] ChipAddress; // hardwired chip addressreg [03:00] BitCounter; // serial bit counterreg START_Rcvd; // START bit received flagreg STOP_Rcvd; // STOP bit received flagreg CTRL_Rcvd; // control byte received flagreg ADDR_Rcvd; // byte address received flagreg MACK_Rcvd; // master acknowledge received flagreg WrCycle; // memory write cyclereg RdCycle; // memory read cyclereg [07:00] ShiftRegister; // input data shift registerreg [07:00] ControlByte; // control byte registerwire BlockSelect; // memory block selectwire RdWrBit; // read/write control bitreg [08:00] StartAddress; // memory access starting addressreg [03:00] PageAddress; // memory page addressreg [07:00] WrDataByte [0:15]; // memory write data bufferwire [07:00] RdDataByte; // memory read datareg [15:00] WrCounter; // write buffer counterreg [03:00] WrPointer; // write buffer pointerreg [08:00] RdPointer; // read address pointerreg WriteActive; // memory write cycle activereg [07:00] MemoryBlock0 [0:255]; // EEPROM data memory arrayreg [07:00] MemoryBlock1 [0:255]; // EEPROM data memory arrayinteger LoopIndex; // iterative loop indexinteger tAA; // timing parameterinteger tWC; // timing parameter// *******************************************************************************************************
// ** INITIALIZATION **
// *******************************************************************************************************initial tAA = 900; // SCL to SDA output delayinitial tWC = 5000000; // memory write cycle timeinitial beginSDA_DO = 0;SDA_OE = 0;endinitial beginSTART_Rcvd = 0;STOP_Rcvd = 0;CTRL_Rcvd = 0;ADDR_Rcvd = 0;MACK_Rcvd = 0;endinitial beginBitCounter = 0;ControlByte = 0;endinitial beginWrCycle = 0;RdCycle = 0;WriteActive = 0;endassign ChipAddress = {A2,A1,A0};// *******************************************************************************************************
// ** CORE LOGIC **
// *******************************************************************************************************
// -------------------------------------------------------------------------------------------------------
// 1.01: START Bit Detection
// -------------------------------------------------------------------------------------------------------always @(negedge SDA) beginif (SCL == 1) beginSTART_Rcvd <= 1;STOP_Rcvd <= 0;CTRL_Rcvd <= 0;ADDR_Rcvd <= 0;MACK_Rcvd <= 0;WrCycle <= #1 0;RdCycle <= #1 0;BitCounter <= 0;endend// -------------------------------------------------------------------------------------------------------
// 1.02: STOP Bit Detection
// -------------------------------------------------------------------------------------------------------always @(posedge SDA) beginif (SCL == 1) beginSTART_Rcvd <= 0;STOP_Rcvd <= 1;CTRL_Rcvd <= 0;ADDR_Rcvd <= 0;MACK_Rcvd <= 0;WrCycle <= #1 0;RdCycle <= #1 0;BitCounter <= 10;endend// -------------------------------------------------------------------------------------------------------
// 1.03: Input Shift Register
// -------------------------------------------------------------------------------------------------------always @(posedge SCL) beginShiftRegister[00] <= SDA;ShiftRegister[01] <= ShiftRegister[00];ShiftRegister[02] <= ShiftRegister[01];ShiftRegister[03] <= ShiftRegister[02];ShiftRegister[04] <= ShiftRegister[03];ShiftRegister[05] <= ShiftRegister[04];ShiftRegister[06] <= ShiftRegister[05];ShiftRegister[07] <= ShiftRegister[06];end// -------------------------------------------------------------------------------------------------------
// 1.04: Input Bit Counter
// -------------------------------------------------------------------------------------------------------always @(posedge SCL) beginif (BitCounter < 10) BitCounter <= BitCounter + 1;end// -------------------------------------------------------------------------------------------------------
// 1.05: Control Byte Register
// -------------------------------------------------------------------------------------------------------always @(negedge SCL) beginif (START_Rcvd & (BitCounter == 8)) beginif (!WriteActive & (ShiftRegister[07:01] == {4'b1010,ChipAddress[02:00]})) beginif (ShiftRegister[00] == 0) WrCycle <= 1;if (ShiftRegister[00] == 1) RdCycle <= 1;ControlByte <= ShiftRegister[07:00];CTRL_Rcvd <= 1;endSTART_Rcvd <= 0;endendassign BlockSelect = ControlByte[01];assign RdWrBit = ControlByte[00];// -------------------------------------------------------------------------------------------------------
// 1.06: Byte Address Register
// -------------------------------------------------------------------------------------------------------always @(negedge SCL) beginif (CTRL_Rcvd & (BitCounter == 8)) beginif (RdWrBit == 0) beginStartAddress <= {BlockSelect,ShiftRegister[07:00]};RdPointer <= {BlockSelect,ShiftRegister[07:00]};ADDR_Rcvd <= 1;endWrCounter <= 0;WrPointer <= 0;CTRL_Rcvd <= 0;endend// -------------------------------------------------------------------------------------------------------
// 1.07: Write Data Buffer
// -------------------------------------------------------------------------------------------------------always @(negedge SCL) beginif (ADDR_Rcvd & (BitCounter == 8)) beginif ((WP == 0) & (RdWrBit == 0)) beginWrDataByte[WrPointer] <= ShiftRegister[07:00];WrCounter <= WrCounter + 1;WrPointer <= WrPointer + 1;endendend// -------------------------------------------------------------------------------------------------------
// 1.08: Acknowledge Generator
// -------------------------------------------------------------------------------------------------------always @(negedge SCL) beginif (!WriteActive) beginif (BitCounter == 8) beginif (WrCycle | (START_Rcvd & (ShiftRegister[07:01] == {4'b1010,ChipAddress[02:00]}))) beginSDA_DO <= 0;SDA_OE <= 1;end endif (BitCounter == 9) beginBitCounter <= 0;if (!RdCycle) beginSDA_DO <= 0;SDA_OE <= 0;endendendend // -------------------------------------------------------------------------------------------------------
// 1.09: Acknowledge Detect
// -------------------------------------------------------------------------------------------------------always @(posedge SCL) beginif (RdCycle & (BitCounter == 8)) beginif ((SDA == 0) & (SDA_OE == 0)) MACK_Rcvd <= 1;endendalways @(negedge SCL) MACK_Rcvd <= 0;// -------------------------------------------------------------------------------------------------------
// 1.10: Write Cycle Timer
// -------------------------------------------------------------------------------------------------------always @(posedge STOP_Rcvd) beginif (WrCycle & (WP == 0) & (WrCounter > 0)) beginWriteActive = 1;#(tWC);WriteActive = 0;endendalways @(posedge STOP_Rcvd) begin#(1.0);STOP_Rcvd = 0;end// -------------------------------------------------------------------------------------------------------
// 1.11: Write Cycle Processor
// -------------------------------------------------------------------------------------------------------always @(negedge WriteActive) beginfor (LoopIndex = 0; LoopIndex < WrCounter; LoopIndex = LoopIndex + 1) beginif (StartAddress[08] == 0) beginPageAddress = StartAddress[03:00] + LoopIndex;MemoryBlock0[{StartAddress[07:04],PageAddress[03:00]}] = WrDataByte[LoopIndex[03:00]];endif (StartAddress[08] == 1) beginPageAddress = StartAddress[03:00] + LoopIndex;MemoryBlock1[{StartAddress[07:04],PageAddress[03:00]}] = WrDataByte[LoopIndex[03:00]];endendend// -------------------------------------------------------------------------------------------------------
// 1.12: Read Data Multiplexor
// -------------------------------------------------------------------------------------------------------always @(negedge SCL) beginif (BitCounter == 8) beginif (WrCycle & ADDR_Rcvd) beginRdPointer <= StartAddress + WrPointer + 1;endif (RdCycle) beginRdPointer <= RdPointer + 1;endendendassign RdDataByte = RdPointer[08] ? MemoryBlock1[RdPointer[07:00]] : MemoryBlock0[RdPointer[07:00]];// -------------------------------------------------------------------------------------------------------
// 1.13: Read Data Processor
// -------------------------------------------------------------------------------------------------------always @(negedge SCL) beginif (RdCycle) beginif (BitCounter == 8) beginSDA_DO <= 0;SDA_OE <= 0;endelse if (BitCounter == 9) beginSDA_DO <= RdDataByte[07];if (MACK_Rcvd) SDA_OE <= 1;endelse beginSDA_DO <= RdDataByte[7-BitCounter];endendend// -------------------------------------------------------------------------------------------------------
// 1.14: SDA Data I/O Buffer
// -------------------------------------------------------------------------------------------------------bufif1 (SDA, 1'b0, SDA_DriveEnableDlyd);assign SDA_DriveEnable = !SDA_DO & SDA_OE;always @(SDA_DriveEnable) SDA_DriveEnableDlyd <= #(tAA) SDA_DriveEnable;// *******************************************************************************************************
// ** DEBUG LOGIC **
// *******************************************************************************************************
// -------------------------------------------------------------------------------------------------------
// 2.01: Memory Data Bytes
// -------------------------------------------------------------------------------------------------------wire [07:00] MemoryByte0_00 = MemoryBlock0[00];wire [07:00] MemoryByte0_01 = MemoryBlock0[01];wire [07:00] MemoryByte0_02 = MemoryBlock0[02];wire [07:00] MemoryByte0_03 = MemoryBlock0[03];wire [07:00] MemoryByte0_04 = MemoryBlock0[04];wire [07:00] MemoryByte0_05 = MemoryBlock0[05];wire [07:00] MemoryByte0_06 = MemoryBlock0[06];wire [07:00] MemoryByte0_07 = MemoryBlock0[07];wire [07:00] MemoryByte0_08 = MemoryBlock0[08];wire [07:00] MemoryByte0_09 = MemoryBlock0[09];wire [07:00] MemoryByte0_0A = MemoryBlock0[10];wire [07:00] MemoryByte0_0B = MemoryBlock0[11];wire [07:00] MemoryByte0_0C = MemoryBlock0[12];wire [07:00] MemoryByte0_0D = MemoryBlock0[13];wire [07:00] MemoryByte0_0E = MemoryBlock0[14];wire [07:00] MemoryByte0_0F = MemoryBlock0[15];wire [07:00] MemoryByte1_00 = MemoryBlock1[00];wire [07:00] MemoryByte1_01 = MemoryBlock1[01];wire [07:00] MemoryByte1_02 = MemoryBlock1[02];wire [07:00] MemoryByte1_03 = MemoryBlock1[03];wire [07:00] MemoryByte1_04 = MemoryBlock1[04];wire [07:00] MemoryByte1_05 = MemoryBlock1[05];wire [07:00] MemoryByte1_06 = MemoryBlock1[06];wire [07:00] MemoryByte1_07 = MemoryBlock1[07];wire [07:00] MemoryByte1_08 = MemoryBlock1[08];wire [07:00] MemoryByte1_09 = MemoryBlock1[09];wire [07:00] MemoryByte1_0A = MemoryBlock1[10];wire [07:00] MemoryByte1_0B = MemoryBlock1[11];wire [07:00] MemoryByte1_0C = MemoryBlock1[12];wire [07:00] MemoryByte1_0D = MemoryBlock1[13];wire [07:00] MemoryByte1_0E = MemoryBlock1[14];wire [07:00] MemoryByte1_0F = MemoryBlock1[15];// -------------------------------------------------------------------------------------------------------
// 2.02: Write Data Buffer
// -------------------------------------------------------------------------------------------------------wire [07:00] WriteData_0 = WrDataByte[00];wire [07:00] WriteData_1 = WrDataByte[01];wire [07:00] WriteData_2 = WrDataByte[02];wire [07:00] WriteData_3 = WrDataByte[03];wire [07:00] WriteData_4 = WrDataByte[04];wire [07:00] WriteData_5 = WrDataByte[05];wire [07:00] WriteData_6 = WrDataByte[06];wire [07:00] WriteData_7 = WrDataByte[07];wire [07:00] WriteData_8 = WrDataByte[08];wire [07:00] WriteData_9 = WrDataByte[09];wire [07:00] WriteData_A = WrDataByte[10];wire [07:00] WriteData_B = WrDataByte[11];wire [07:00] WriteData_C = WrDataByte[12];wire [07:00] WriteData_D = WrDataByte[13];wire [07:00] WriteData_E = WrDataByte[14];wire [07:00] WriteData_F = WrDataByte[15];// *******************************************************************************************************
// ** TIMING CHECKS **
// *******************************************************************************************************wire TimingCheckEnable = (RESET == 0) & (SDA_OE == 0);specifyspecparamtHI = 600, // SCL pulse width - hightLO = 1300, // SCL pulse width - lowtSU_STA = 600, // SCL to SDA setup timetHD_STA = 600, // SCL to SDA hold timetSU_DAT = 100, // SDA to SCL setup timetSU_STO = 600, // SCL to SDA setup timetBUF = 1300; // Bus free time$width (posedge SCL, tHI);$width (negedge SCL, tLO);$width (posedge SDA &&& SCL, tBUF);$setup (posedge SCL, negedge SDA &&& TimingCheckEnable, tSU_STA);$setup (SDA, posedge SCL &&& TimingCheckEnable, tSU_DAT);$setup (posedge SCL, posedge SDA &&& TimingCheckEnable, tSU_STO);$hold (negedge SDA &&& TimingCheckEnable, negedge SCL, tHD_STA);endspecifyendmodule2、M24LC64仿真模型供大家使用
// *******************************************************************************************************
// ** **
// ** 24LC64.v - Microchip 24LC64 64K-BIT I2C SERIAL EEPROM (VCC = +2.5V TO +5.5V) **
// ** **
// *******************************************************************************************************
// ** **
// ** This information is distributed under license from Young Engineering. **
// ** COPYRIGHT (c) 2009 YOUNG ENGINEERING **
// ** ALL RIGHTS RESERVED **
// ** **
// ** **
// ** Young Engineering provides design expertise for the digital world **
// ** Started in 1990, Young Engineering offers products and services for your electronic design **
// ** project. We have the expertise in PCB, FPGA, ASIC, firmware, and software design. **
// ** From concept to prototype to production, we can help you. **
// ** **
// ** http://www.young-engineering.com/ **
// ** **
// *******************************************************************************************************
// ** This information is provided to you for your convenience and use with Microchip products only. **
// ** Microchip disclaims all liability arising from this information and its use. **
// ** **
// ** THIS INFORMATION IS PROVIDED "AS IS." MICROCHIP MAKES NO REPRESENTATION OR WARRANTIES OF **
// ** ANY KIND WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL, STATUTORY OR OTHERWISE, RELATED TO **
// ** THE INFORMATION PROVIDED TO YOU, INCLUDING BUT NOT LIMITED TO ITS CONDITION, QUALITY, **
// ** PERFORMANCE, MERCHANTABILITY, NON-INFRINGEMENT, OR FITNESS FOR PURPOSE. **
// ** MICROCHIP IS NOT LIABLE, UNDER ANY CIRCUMSTANCES, FOR SPECIAL, INCIDENTAL OR CONSEQUENTIAL **
// ** DAMAGES, FOR ANY REASON WHATSOEVER. **
// ** **
// ** It is your responsibility to ensure that your application meets with your specifications. **
// ** **
// *******************************************************************************************************
// ** Revision : 1.4 **
// ** Modified Date : 02/04/2009 **
// ** Revision History: **
// ** **
// ** 10/01/2003: Initial design **
// ** 07/19/2004: Fixed the timing checks and the open-drain modeling for SDA. **
// ** 01/06/2006: Changed the legal information in the header **
// ** 12/04/2006: Corrected timing checks to reference proper clock edges **
// ** Added timing check for Tbuf (bus free time) **
// ** Reduced memory blocks to single, monolithic array **
// ** 02/04/2009: Added timing checks for tSU_WP and tHD_WP **
// ** **
// *******************************************************************************************************
// ** TABLE OF CONTENTS **
// *******************************************************************************************************
// **---------------------------------------------------------------------------------------------------**
// ** DECLARATIONS **
// **---------------------------------------------------------------------------------------------------**
// **---------------------------------------------------------------------------------------------------**
// ** INITIALIZATION **
// **---------------------------------------------------------------------------------------------------**
// **---------------------------------------------------------------------------------------------------**
// ** CORE LOGIC **
// **---------------------------------------------------------------------------------------------------**
// ** 1.01: START Bit Detection **
// ** 1.02: STOP Bit Detection **
// ** 1.03: Input Shift Register **
// ** 1.04: Input Bit Counter **
// ** 1.05: Control Byte Register **
// ** 1.06: Byte Address Register **
// ** 1.07: Write Data Buffer **
// ** 1.08: Acknowledge Generator **
// ** 1.09: Acknowledge Detect **
// ** 1.10: Write Cycle Timer **
// ** 1.11: Write Cycle Processor **
// ** 1.12: Read Data Multiplexor **
// ** 1.13: Read Data Processor **
// ** 1.14: SDA Data I/O Buffer **
// ** **
// **---------------------------------------------------------------------------------------------------**
// ** DEBUG LOGIC **
// **---------------------------------------------------------------------------------------------------**
// ** 2.01: Memory Data Bytes **
// ** 2.02: Write Data Buffer **
// ** **
// **---------------------------------------------------------------------------------------------------**
// ** TIMING CHECKS **
// **---------------------------------------------------------------------------------------------------**
// ** **
// *******************************************************************************************************`timescale 1ns/10psmodule M24LC64 (A0, A1, A2, WP, SDA, SCL, RESET);input A0; // chip select bitinput A1; // chip select bitinput A2; // chip select bitinput WP; // write protect pininout SDA; // serial data I/Oinput SCL; // serial data clockinput RESET; // system reset// *******************************************************************************************************
// ** DECLARATIONS **
// *******************************************************************************************************reg SDA_DO; // serial data - outputreg SDA_OE; // serial data - output enablewire SDA_DriveEnable; // serial data output enablereg SDA_DriveEnableDlyd; // serial data output enable - delayedwire [02:00] ChipAddress; // hardwired chip addressreg [03:00] BitCounter; // serial bit counterreg START_Rcvd; // START bit received flagreg STOP_Rcvd; // STOP bit received flagreg CTRL_Rcvd; // control byte received flagreg ADHI_Rcvd; // byte address hi received flagreg ADLO_Rcvd; // byte address lo received flagreg MACK_Rcvd; // master acknowledge received flagreg WrCycle; // memory write cyclereg RdCycle; // memory read cyclereg [07:00] ShiftRegister; // input data shift registerreg [07:00] ControlByte; // control byte registerwire RdWrBit; // read/write control bitreg [12:00] StartAddress; // memory access starting addressreg [04:00] PageAddress; // memory page addressreg [07:00] WrDataByte [0:31]; // memory write data bufferwire [07:00] RdDataByte; // memory read datareg [15:00] WrCounter; // write buffer counterreg [04:00] WrPointer; // write buffer pointerreg [12:00] RdPointer; // read address pointerreg WriteActive; // memory write cycle activereg [07:00] MemoryBlock [0:8191]; // EEPROM data memory arrayinteger LoopIndex; // iterative loop indexinteger tAA; // timing parameterinteger tWC; // timing parameter// *******************************************************************************************************
// ** INITIALIZATION **
// *******************************************************************************************************//----------------------------
//------写数据间隔改动----------initial tAA = 900; // SCL to SDA output delayinitial tWC = 500; // memory write cycle time// initial tAA = 900; // SCL to SDA output delay
// initial tWC = 5000000; // memory write cycle timeinitial beginSDA_DO = 0;SDA_OE = 0;endinitial beginSTART_Rcvd = 0;STOP_Rcvd = 0;CTRL_Rcvd = 0;ADHI_Rcvd = 0;ADLO_Rcvd = 0;MACK_Rcvd = 0;endinitial beginBitCounter = 0;ControlByte = 0;endinitial beginWrCycle = 0;RdCycle = 0;WriteActive = 0;endassign ChipAddress = {A2,A1,A0};// *******************************************************************************************************
// ** CORE LOGIC **
// *******************************************************************************************************
// -------------------------------------------------------------------------------------------------------
// 1.01: START Bit Detection
// -------------------------------------------------------------------------------------------------------always @(negedge SDA) beginif (SCL == 1) beginSTART_Rcvd <= 1;STOP_Rcvd <= 0;CTRL_Rcvd <= 0;ADHI_Rcvd <= 0;ADLO_Rcvd <= 0;MACK_Rcvd <= 0;WrCycle <= #1 0;RdCycle <= #1 0;BitCounter <= 0;endend// -------------------------------------------------------------------------------------------------------
// 1.02: STOP Bit Detection
// -------------------------------------------------------------------------------------------------------always @(posedge SDA) beginif (SCL == 1) beginSTART_Rcvd <= 0;STOP_Rcvd <= 1;CTRL_Rcvd <= 0;ADHI_Rcvd <= 0;ADLO_Rcvd <= 0;MACK_Rcvd <= 0;WrCycle <= #1 0;RdCycle <= #1 0;BitCounter <= 10;endend// -------------------------------------------------------------------------------------------------------
// 1.03: Input Shift Register
// -------------------------------------------------------------------------------------------------------always @(posedge SCL) beginShiftRegister[00] <= SDA;ShiftRegister[01] <= ShiftRegister[00];ShiftRegister[02] <= ShiftRegister[01];ShiftRegister[03] <= ShiftRegister[02];ShiftRegister[04] <= ShiftRegister[03];ShiftRegister[05] <= ShiftRegister[04];ShiftRegister[06] <= ShiftRegister[05];ShiftRegister[07] <= ShiftRegister[06];end// -------------------------------------------------------------------------------------------------------
// 1.04: Input Bit Counter
// -------------------------------------------------------------------------------------------------------always @(posedge SCL) beginif (BitCounter < 10) BitCounter <= BitCounter + 1;end// -------------------------------------------------------------------------------------------------------
// 1.05: Control Byte Register
// -------------------------------------------------------------------------------------------------------always @(negedge SCL) beginif (START_Rcvd & (BitCounter == 8)) beginif (!WriteActive & (ShiftRegister[07:01] == {4'b1010,ChipAddress[02:00]})) beginif (ShiftRegister[00] == 0) WrCycle <= 1;if (ShiftRegister[00] == 1) RdCycle <= 1;ControlByte <= ShiftRegister[07:00];CTRL_Rcvd <= 1;endSTART_Rcvd <= 0;endendassign RdWrBit = ControlByte[00];// -------------------------------------------------------------------------------------------------------
// 1.06: Byte Address Register
// -------------------------------------------------------------------------------------------------------always @(negedge SCL) beginif (CTRL_Rcvd & (BitCounter == 8)) beginif (RdWrBit == 0) beginStartAddress[12:08] <= ShiftRegister[04:00];RdPointer[12:08] <= ShiftRegister[04:00];ADHI_Rcvd <= 1;endWrCounter <= 0;WrPointer <= 0;CTRL_Rcvd <= 0;endendalways @(negedge SCL) beginif (ADHI_Rcvd & (BitCounter == 8)) beginif (RdWrBit == 0) beginStartAddress[07:00] <= ShiftRegister[07:00];RdPointer[07:00] <= ShiftRegister[07:00];ADLO_Rcvd <= 1;endWrCounter <= 0;WrPointer <= 0;ADHI_Rcvd <= 0;endend// -------------------------------------------------------------------------------------------------------
// 1.07: Write Data Buffer
// -------------------------------------------------------------------------------------------------------always @(negedge SCL) beginif (ADLO_Rcvd & (BitCounter == 8)) beginif (RdWrBit == 0) beginWrDataByte[WrPointer] <= ShiftRegister[07:00];WrCounter <= WrCounter + 1;WrPointer <= WrPointer + 1;endendend// -------------------------------------------------------------------------------------------------------
// 1.08: Acknowledge Generator
// -------------------------------------------------------------------------------------------------------always @(negedge SCL) beginif (!WriteActive) beginif (BitCounter == 8) beginif (WrCycle | (START_Rcvd & (ShiftRegister[07:01] == {4'b1010,ChipAddress[02:00]}))) beginSDA_DO <= 0;SDA_OE <= 1;end endif (BitCounter == 9) beginBitCounter <= 0;if (!RdCycle) beginSDA_DO <= 0;SDA_OE <= 0;endendendend // -------------------------------------------------------------------------------------------------------
// 1.09: Acknowledge Detect
// -------------------------------------------------------------------------------------------------------always @(posedge SCL) beginif (RdCycle & (BitCounter == 8)) beginif ((SDA == 0) & (SDA_OE == 0)) MACK_Rcvd <= 1;endendalways @(negedge SCL) MACK_Rcvd <= 0;// -------------------------------------------------------------------------------------------------------
// 1.10: Write Cycle Timer
// -------------------------------------------------------------------------------------------------------always @(posedge STOP_Rcvd) beginif (WrCycle & (WP == 0) & (WrCounter > 0)) beginWriteActive = 1;#(tWC);WriteActive = 0;endendalways @(posedge STOP_Rcvd) begin#(1.0);STOP_Rcvd = 0;end// -------------------------------------------------------------------------------------------------------
// 1.11: Write Cycle Processor
// -------------------------------------------------------------------------------------------------------always @(negedge WriteActive) beginfor (LoopIndex = 0; LoopIndex < WrCounter; LoopIndex = LoopIndex + 1) beginPageAddress = StartAddress[04:00] + LoopIndex;MemoryBlock[{StartAddress[12:05],PageAddress[04:00]}] = WrDataByte[LoopIndex[04:00]];endend// -------------------------------------------------------------------------------------------------------
// 1.12: Read Data Multiplexor
// -------------------------------------------------------------------------------------------------------always @(negedge SCL) beginif (BitCounter == 8) beginif (WrCycle & ADLO_Rcvd) beginRdPointer <= StartAddress + WrPointer + 1;endif (RdCycle) beginRdPointer <= RdPointer + 1;endendendassign RdDataByte = MemoryBlock[RdPointer[12:00]];// -------------------------------------------------------------------------------------------------------
// 1.13: Read Data Processor
// -------------------------------------------------------------------------------------------------------always @(negedge SCL) beginif (RdCycle) beginif (BitCounter == 8) beginSDA_DO <= 0;SDA_OE <= 0;endelse if (BitCounter == 9) beginSDA_DO <= RdDataByte[07];if (MACK_Rcvd) SDA_OE <= 1;endelse beginSDA_DO <= RdDataByte[7-BitCounter];endendend// -------------------------------------------------------------------------------------------------------
// 1.14: SDA Data I/O Buffer
// -------------------------------------------------------------------------------------------------------bufif1 (SDA, 1'b0, SDA_DriveEnableDlyd);assign SDA_DriveEnable = !SDA_DO & SDA_OE;always @(SDA_DriveEnable) SDA_DriveEnableDlyd <= #(tAA) SDA_DriveEnable;// *******************************************************************************************************
// ** DEBUG LOGIC **
// *******************************************************************************************************
// -------------------------------------------------------------------------------------------------------
// 2.01: Memory Data Bytes
// -------------------------------------------------------------------------------------------------------wire [07:00] MemoryByte_000 = MemoryBlock[00];wire [07:00] MemoryByte_001 = MemoryBlock[01];wire [07:00] MemoryByte_002 = MemoryBlock[02];wire [07:00] MemoryByte_003 = MemoryBlock[03];wire [07:00] MemoryByte_004 = MemoryBlock[04];wire [07:00] MemoryByte_005 = MemoryBlock[05];wire [07:00] MemoryByte_006 = MemoryBlock[06];wire [07:00] MemoryByte_007 = MemoryBlock[07];wire [07:00] MemoryByte_008 = MemoryBlock[08];wire [07:00] MemoryByte_009 = MemoryBlock[09];wire [07:00] MemoryByte_00A = MemoryBlock[10];wire [07:00] MemoryByte_00B = MemoryBlock[11];wire [07:00] MemoryByte_00C = MemoryBlock[12];wire [07:00] MemoryByte_00D = MemoryBlock[13];wire [07:00] MemoryByte_00E = MemoryBlock[14];wire [07:00] MemoryByte_00F = MemoryBlock[15];// -------------------------------------------------------------------------------------------------------
// 2.02: Write Data Buffer
// -------------------------------------------------------------------------------------------------------wire [07:00] WriteData_00 = WrDataByte[00];wire [07:00] WriteData_01 = WrDataByte[01];wire [07:00] WriteData_02 = WrDataByte[02];wire [07:00] WriteData_03 = WrDataByte[03];wire [07:00] WriteData_04 = WrDataByte[04];wire [07:00] WriteData_05 = WrDataByte[05];wire [07:00] WriteData_06 = WrDataByte[06];wire [07:00] WriteData_07 = WrDataByte[07];wire [07:00] WriteData_08 = WrDataByte[08];wire [07:00] WriteData_09 = WrDataByte[09];wire [07:00] WriteData_0A = WrDataByte[10];wire [07:00] WriteData_0B = WrDataByte[11];wire [07:00] WriteData_0C = WrDataByte[12];wire [07:00] WriteData_0D = WrDataByte[13];wire [07:00] WriteData_0E = WrDataByte[14];wire [07:00] WriteData_0F = WrDataByte[15];wire [07:00] WriteData_10 = WrDataByte[16];wire [07:00] WriteData_11 = WrDataByte[17];wire [07:00] WriteData_12 = WrDataByte[18];wire [07:00] WriteData_13 = WrDataByte[19];wire [07:00] WriteData_14 = WrDataByte[20];wire [07:00] WriteData_15 = WrDataByte[21];wire [07:00] WriteData_16 = WrDataByte[22];wire [07:00] WriteData_17 = WrDataByte[23];wire [07:00] WriteData_18 = WrDataByte[24];wire [07:00] WriteData_19 = WrDataByte[25];wire [07:00] WriteData_1A = WrDataByte[26];wire [07:00] WriteData_1B = WrDataByte[27];wire [07:00] WriteData_1C = WrDataByte[28];wire [07:00] WriteData_1D = WrDataByte[29];wire [07:00] WriteData_1E = WrDataByte[30];wire [07:00] WriteData_1F = WrDataByte[31];// *******************************************************************************************************
// ** TIMING CHECKS **
// *******************************************************************************************************wire TimingCheckEnable = (RESET == 0) & (SDA_OE == 0);wire StopTimingCheckEnable = TimingCheckEnable && SCL;//--------------------------------
//-------仿真时时序约束需改动--------
//--------------------------------specifyspecparamtHI = 600, // SCL pulse width - high
// tLO = 1300, // SCL pulse width - lowtLO = 600, tSU_STA = 600, // SCL to SDA setup timetHD_STA = 600, // SCL to SDA hold timetSU_DAT = 100, // SDA to SCL setup timetSU_STO = 600, // SCL to SDA setup timetSU_WP = 600, // WP to SDA setup timetHD_WP = 1300, // WP to SDA hold time
// tBUF = 1300; // Bus free timetBUF = 600; $width (posedge SCL, tHI);$width (negedge SCL, tLO);$width (posedge SDA &&& SCL, tBUF);$setup (posedge SCL, negedge SDA &&& TimingCheckEnable, tSU_STA);$setup (SDA, posedge SCL &&& TimingCheckEnable, tSU_DAT);$setup (posedge SCL, posedge SDA &&& TimingCheckEnable, tSU_STO);$setup (WP, posedge SDA &&& StopTimingCheckEnable, tSU_WP);$hold (negedge SDA &&& TimingCheckEnable, negedge SCL, tHD_STA);$hold (posedge SDA &&& StopTimingCheckEnable, WP, tHD_WP);endspecifyendmodule三、testbench文件
`timescale 1ns / 1ps
module i2c_bit_shift_tb;reg Clk;reg Rst_n;reg [5:0] Cmd;reg Go;wire [7:0] Rx_DATA;reg [7:0] Tx_DATA;wire Trans_Done;wire ack_o;wire i2c_sclk;wire i2c_sdat;pullup PUP(i2c_sdat);localparam WR = 6'b000001, //写请求STA = 6'b000010, //起始位请求RD = 6'b000100, //读请求STO = 6'b001000, //停止位请求ACK = 6'b010000, //应答位请求NACK = 6'b100000; //无应答请求i2c_bit_shift DUT(.Clk(Clk),.Rst_n(Rst_n),.Cmd(Cmd),.Go(Go),.Rx_DATA(Rx_DATA),.Tx_DATA(Tx_DATA),.Trans_Done(Trans_Done),.ack_o(ack_o),.i2c_sclk(i2c_sclk),.i2c_sdat(i2c_sdat));M24LC04B M24LC04B(.A0(0), .A1(0), .A2(0), .WP(0), .SDA(i2c_sdat), .SCL(i2c_sclk), .RESET(~Rst_n));always #10 Clk = ~Clk;initial beginClk = 1;Rst_n = 0;Cmd = 6'b000000;Go = 0;Tx_DATA = 8'd0;#2001;Rst_n = 1;#2000;//写数据操作，往EEPROM器件的B1地址写数据DA//第一次：起始位+EEPROM器件地址（7位）+写方向（1位）Cmd = STA | WR;Go = 1;Tx_DATA = 8'hA0 | 8'd0;//写方向@ (posedge Clk);Go = 0;@ (posedge Trans_Done);#200;//第二次：写8位EEPROM的寄存器地址Cmd = WR;Go = 1;Tx_DATA = 8'hB1;//写地址B1@ (posedge Clk);Go = 0;@ (posedge Trans_Done);#200;//第三次：写8位数据 + 停止位Cmd = WR | STO;Go = 1;Tx_DATA = 8'hda;//写数据DA@ (posedge Clk);Go = 0;@ (posedge Trans_Done);#200;#5000000; //仿真模型的两次操作时间间隔//读数据操作，从EEPROM器件的B1地址读数据//第一次：起始位+EEPROM器件地址（7位）+写方向（1位）Cmd = STA | WR;Go = 1;Tx_DATA = 8'hA0 | 8'd0;//写方向@ (posedge Clk);Go = 0;@ (posedge Trans_Done);#200;//第二次：写8位EEPROM的寄存器地址Cmd = WR;Go = 1;Tx_DATA = 8'hB1;//写地址B1@ (posedge Clk);Go = 0;@ (posedge Trans_Done);#200;//第三次：起始位+EEPROM器件地址（7位）+读方向（1位）Cmd = STA | WR;Go = 1;Tx_DATA = 8'hA0 | 8'd1;//读方向@ (posedge Clk);Go = 0;@ (posedge Trans_Done);#200;//第四次：读8位数据 + 停止位Cmd = RD | STO;Go = 1;@ (posedge Clk);Go = 0;@ (posedge Trans_Done);#200;#2000;$stop;endendmodule`timescale 1ns / 1ps
//
// Company:
// Engineer:
//
// Create Date: 2019/10/23 23:32:08
// Design Name:
// Module Name: i2c_control_tb
// Project Name:
// Target Devices:
// Tool Versions:
// Description:
//
// Dependencies:
//
// Revision:
// Revision 0.01 - File Created
// Additional Comments:
//
//module i2c_control_tb;reg Clk;reg Rst_n;reg wrreg_req;reg rdreg_req;reg [15:0]addr;reg addr_mode;reg [7:0]wrdata;wire [7:0]rddata;reg [7:0]device_id;wire RW_Done;wire ack;wire i2c_sclk;wire i2c_sdat;pullup PUP(i2c_sdat);i2c_control DUT(.Clk (Clk ),.Rst_n (Rst_n ),.wrreg_req (wrreg_req),.rdreg_req (rdreg_req),.addr (addr ),.addr_mode (addr_mode),.wrdata (wrdata ),.rddata (rddata ),.device_id (device_id),.RW_Done (RW_Done ),.ack (ack ),.i2c_sclk (i2c_sclk ),.i2c_sdat (i2c_sdat ));M24LC04B M24LC04B(.A0(0), .A1(0), .A2(0), .WP(0), .SDA(i2c_sdat), .SCL(i2c_sclk), .RESET(~Rst_n));initial Clk = 1;always #10 Clk = ~Clk;initial beginRst_n = 0;rdreg_req = 0;wrreg_req = 0;#2001;Rst_n = 1;#2000;write_one_byte(8'hA0,8'h0A,8'hd1);write_one_byte(8'hA0,8'h0B,8'hd2);write_one_byte(8'hA0,8'h0C,8'hd3);write_one_byte(8'hA0,8'h0F,8'hd4);read_one_byte(8'hA0,8'h0A);read_one_byte(8'hA0,8'h0B);read_one_byte(8'hA0,8'h0C);read_one_byte(8'hA0,8'h0F);$stop; endtask write_one_byte;input [7:0]id;input [7:0]mem_address; input [7:0]data;beginaddr = {8'd0,mem_address};device_id = id;addr_mode = 0;wrdata = data;wrreg_req = 1;#20;wrreg_req = 0;@(posedge RW_Done);#5000000;endendtasktask read_one_byte;input [7:0]id;input [7:0]mem_address; beginaddr = {8'd0,mem_address};device_id = id;addr_mode = 0;rdreg_req = 1;#20;rdreg_req = 0;@(posedge RW_Done);#5000000;endendtaskendmodule四、完整工程下载
芯路恒的开源工程，需要的自提。附文档。
链接：https://pan.baidu.com/s/1wdAYkX4ricvnc7v8yUNgRQ?pwd=FBMZ
提取码：FBMZ
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