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|
/////////////////////////////////////////////////////////////////////
//// ////
//// WISHBONE rev.B2 compliant I2C Master controller Testbench ////
//// ////
//// ////
//// Author: Richard Herveille ////
//// richard@asics.ws ////
//// www.asics.ws ////
//// ////
//// Downloaded from: http://www.opencores.org/projects/i2c/ ////
//// ////
/////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2001 Richard Herveille ////
//// richard@asics.ws ////
//// ////
//// This source file may be used and distributed without ////
//// restriction provided that this copyright statement is not ////
//// removed from the file and that any derivative work contains ////
//// the original copyright notice and the associated disclaimer.////
//// ////
//// THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY ////
//// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED ////
//// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS ////
//// FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR ////
//// OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, ////
//// INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES ////
//// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE ////
//// GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR ////
//// BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF ////
//// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT ////
//// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT ////
//// OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE ////
//// POSSIBILITY OF SUCH DAMAGE. ////
//// ////
/////////////////////////////////////////////////////////////////////
// CVS Log
//
// $Id: tst_bench_top.v,v 1.8 2006-09-04 09:08:51 rherveille Exp $
//
// $Date: 2006-09-04 09:08:51 $
// $Revision: 1.8 $
// $Author: rherveille $
// $Locker: $
// $State: Exp $
//
// Change History:
// $Log: not supported by cvs2svn $
// Revision 1.7 2005/02/27 09:24:18 rherveille
// Fixed scl, sda delay.
//
// Revision 1.6 2004/02/28 15:40:42 rherveille
// *** empty log message ***
//
// Revision 1.4 2003/12/05 11:04:38 rherveille
// Added slave address configurability
//
// Revision 1.3 2002/10/30 18:11:06 rherveille
// Added timing tests to i2c_model.
// Updated testbench.
//
// Revision 1.2 2002/03/17 10:26:38 rherveille
// Fixed some race conditions in the i2c-slave model.
// Added debug information.
// Added headers.
//
`timescale 1ns / 10ps
module tst_bench_top();
//
// wires && regs
//
reg clk;
reg rstn;
wire [31:0] adr;
wire [ 7:0] dat_i, dat_o, dat0_i, dat1_i;
wire we;
wire stb;
wire cyc;
wire ack;
wire inta;
reg [7:0] q, qq;
wire scl, scl0_o, scl0_oen, scl1_o, scl1_oen;
wire sda, sda0_o, sda0_oen, sda1_o, sda1_oen;
parameter PRER_LO = 3'b000;
parameter PRER_HI = 3'b001;
parameter CTR = 3'b010;
parameter RXR = 3'b011;
parameter TXR = 3'b011;
parameter CR = 3'b100;
parameter SR = 3'b100;
parameter TXR_R = 3'b101; // undocumented / reserved output
parameter CR_R = 3'b110; // undocumented / reserved output
parameter RD = 1'b1;
parameter WR = 1'b0;
parameter SADR = 7'b0010_000;
//
// Module body
//
// generate clock
always #5 clk = ~clk;
// hookup wishbone master model
wb_master_model #(8, 32) u0 (
.clk(clk),
.rst(rstn),
.adr(adr),
.din(dat_i),
.dout(dat_o),
.cyc(cyc),
.stb(stb),
.we(we),
.sel(),
.ack(ack),
.err(1'b0),
.rty(1'b0)
);
wire stb0 = stb & ~adr[3];
wire stb1 = stb & adr[3];
assign dat_i = ({{8'd8}{stb0}} & dat0_i) | ({{8'd8}{stb1}} & dat1_i);
// hookup wishbone_i2c_master core
i2c_master_top i2c_top (
// wishbone interface
.wb_clk_i(clk),
.wb_rst_i(1'b0),
.arst_i(rstn),
.wb_adr_i(adr[2:0]),
.wb_dat_i(dat_o),
.wb_dat_o(dat0_i),
.wb_we_i(we),
.wb_stb_i(stb0),
.wb_cyc_i(cyc),
.wb_ack_o(ack),
.wb_inta_o(inta),
// i2c signals
.scl_pad_i(scl),
.scl_pad_o(scl0_o),
.scl_padoen_o(scl0_oen),
.sda_pad_i(sda),
.sda_pad_o(sda0_o),
.sda_padoen_o(sda0_oen)
),
i2c_top2 (
// wishbone interface
.wb_clk_i(clk),
.wb_rst_i(1'b0),
.arst_i(rstn),
.wb_adr_i(adr[2:0]),
.wb_dat_i(dat_o),
.wb_dat_o(dat1_i),
.wb_we_i(we),
.wb_stb_i(stb1),
.wb_cyc_i(cyc),
.wb_ack_o(ack),
.wb_inta_o(inta),
// i2c signals
.scl_pad_i(scl),
.scl_pad_o(scl1_o),
.scl_padoen_o(scl1_oen),
.sda_pad_i(sda),
.sda_pad_o(sda1_o),
.sda_padoen_o(sda1_oen)
);
// hookup i2c slave model
i2c_slave_model #(SADR) i2c_slave (
.scl(scl),
.sda(sda)
);
// create i2c lines
delay m0_scl (scl0_oen ? 1'bz : scl0_o, scl),
m1_scl (scl1_oen ? 1'bz : scl1_o, scl),
m0_sda (sda0_oen ? 1'bz : sda0_o, sda),
m1_sda (sda1_oen ? 1'bz : sda1_o, sda);
pullup p1(scl); // pullup scl line
pullup p2(sda); // pullup sda line
initial
begin
`ifdef WAVES
$shm_open("waves");
$shm_probe("AS",tst_bench_top,"AS");
$display("INFO: Signal dump enabled ...\n\n");
`endif
force i2c_slave.debug = 1'b1; // enable i2c_slave debug information
// force i2c_slave.debug = 1'b0; // disable i2c_slave debug information
$display("\nstatus: %t Testbench started\n\n", $time);
// $dumpfile("bench.vcd");
// $dumpvars(1, tst_bench_top);
// $dumpvars(1, tst_bench_top.i2c_slave);
// initially values
clk = 0;
// reset system
rstn = 1'b1; // negate reset
#2;
rstn = 1'b0; // assert reset
repeat(1) @(posedge clk);
rstn = 1'b1; // negate reset
$display("status: %t done reset", $time);
@(posedge clk);
//
// program core
//
// program internal registers
u0.wb_write(1, PRER_LO, 8'hfa); // load prescaler lo-byte
u0.wb_write(1, PRER_LO, 8'hc8); // load prescaler lo-byte
u0.wb_write(1, PRER_HI, 8'h00); // load prescaler hi-byte
$display("status: %t programmed registers", $time);
u0.wb_cmp(0, PRER_LO, 8'hc8); // verify prescaler lo-byte
u0.wb_cmp(0, PRER_HI, 8'h00); // verify prescaler hi-byte
$display("status: %t verified registers", $time);
u0.wb_write(1, CTR, 8'h80); // enable core
$display("status: %t core enabled", $time);
//
// access slave (write)
//
// drive slave address
u0.wb_write(1, TXR, {SADR,WR} ); // present slave address, set write-bit
u0.wb_write(0, CR, 8'h90 ); // set command (start, write)
$display("status: %t generate 'start', write cmd %0h (slave address+write)", $time, {SADR,WR} );
// check tip bit
u0.wb_read(1, SR, q);
while(q[1])
u0.wb_read(0, SR, q); // poll it until it is zero
$display("status: %t tip==0", $time);
// send memory address
u0.wb_write(1, TXR, 8'h01); // present slave's memory address
u0.wb_write(0, CR, 8'h10); // set command (write)
$display("status: %t write slave memory address 01", $time);
// check tip bit
u0.wb_read(1, SR, q);
while(q[1])
u0.wb_read(0, SR, q); // poll it until it is zero
$display("status: %t tip==0", $time);
// send memory contents
u0.wb_write(1, TXR, 8'ha5); // present data
u0.wb_write(0, CR, 8'h10); // set command (write)
$display("status: %t write data a5", $time);
while (scl) #1;
force scl= 1'b0;
#100000;
release scl;
// check tip bit
u0.wb_read(1, SR, q);
while(q[1])
u0.wb_read(1, SR, q); // poll it until it is zero
$display("status: %t tip==0", $time);
// send memory contents for next memory address (auto_inc)
u0.wb_write(1, TXR, 8'h5a); // present data
u0.wb_write(0, CR, 8'h50); // set command (stop, write)
$display("status: %t write next data 5a, generate 'stop'", $time);
// check tip bit
u0.wb_read(1, SR, q);
while(q[1])
u0.wb_read(1, SR, q); // poll it until it is zero
$display("status: %t tip==0", $time);
//
// delay
//
// #100000; // wait for 100us.
// $display("status: %t wait 100us", $time);
//
// access slave (read)
//
// drive slave address
u0.wb_write(1, TXR,{SADR,WR} ); // present slave address, set write-bit
u0.wb_write(0, CR, 8'h90 ); // set command (start, write)
$display("status: %t generate 'start', write cmd %0h (slave address+write)", $time, {SADR,WR} );
// check tip bit
u0.wb_read(1, SR, q);
while(q[1])
u0.wb_read(1, SR, q); // poll it until it is zero
$display("status: %t tip==0", $time);
// send memory address
u0.wb_write(1, TXR, 8'h01); // present slave's memory address
u0.wb_write(0, CR, 8'h10); // set command (write)
$display("status: %t write slave address 01", $time);
// check tip bit
u0.wb_read(1, SR, q);
while(q[1])
u0.wb_read(1, SR, q); // poll it until it is zero
$display("status: %t tip==0", $time);
// drive slave address
u0.wb_write(1, TXR, {SADR,RD} ); // present slave's address, set read-bit
u0.wb_write(0, CR, 8'h90 ); // set command (start, write)
$display("status: %t generate 'repeated start', write cmd %0h (slave address+read)", $time, {SADR,RD} );
// check tip bit
u0.wb_read(1, SR, q);
while(q[1])
u0.wb_read(1, SR, q); // poll it until it is zero
$display("status: %t tip==0", $time);
// read data from slave
u0.wb_write(1, CR, 8'h20); // set command (read, ack_read)
$display("status: %t read + ack", $time);
// check tip bit
u0.wb_read(1, SR, q);
while(q[1])
u0.wb_read(1, SR, q); // poll it until it is zero
$display("status: %t tip==0", $time);
// check data just received
u0.wb_read(1, RXR, qq);
if(qq !== 8'ha5)
$display("\nERROR: Expected a5, received %x at time %t", qq, $time);
else
$display("status: %t received %x", $time, qq);
// read data from slave
u0.wb_write(1, CR, 8'h20); // set command (read, ack_read)
$display("status: %t read + ack", $time);
// check tip bit
u0.wb_read(1, SR, q);
while(q[1])
u0.wb_read(1, SR, q); // poll it until it is zero
$display("status: %t tip==0", $time);
// check data just received
u0.wb_read(1, RXR, qq);
if(qq !== 8'h5a)
$display("\nERROR: Expected 5a, received %x at time %t", qq, $time);
else
$display("status: %t received %x", $time, qq);
// read data from slave
u0.wb_write(1, CR, 8'h20); // set command (read, ack_read)
$display("status: %t read + ack", $time);
// check tip bit
u0.wb_read(1, SR, q);
while(q[1])
u0.wb_read(1, SR, q); // poll it until it is zero
$display("status: %t tip==0", $time);
// check data just received
u0.wb_read(1, RXR, qq);
$display("status: %t received %x from 3rd read address", $time, qq);
// read data from slave
u0.wb_write(1, CR, 8'h28); // set command (read, nack_read)
$display("status: %t read + nack", $time);
// check tip bit
u0.wb_read(1, SR, q);
while(q[1])
u0.wb_read(1, SR, q); // poll it until it is zero
$display("status: %t tip==0", $time);
// check data just received
u0.wb_read(1, RXR, qq);
$display("status: %t received %x from 4th read address", $time, qq);
//
// check invalid slave memory address
//
// drive slave address
u0.wb_write(1, TXR, {SADR,WR} ); // present slave address, set write-bit
u0.wb_write(0, CR, 8'h90 ); // set command (start, write)
$display("status: %t generate 'start', write cmd %0h (slave address+write). Check invalid address", $time, {SADR,WR} );
// check tip bit
u0.wb_read(1, SR, q);
while(q[1])
u0.wb_read(1, SR, q); // poll it until it is zero
$display("status: %t tip==0", $time);
// send memory address
u0.wb_write(1, TXR, 8'h10); // present slave's memory address
u0.wb_write(0, CR, 8'h10); // set command (write)
$display("status: %t write slave memory address 10", $time);
// check tip bit
u0.wb_read(1, SR, q);
while(q[1])
u0.wb_read(1, SR, q); // poll it until it is zero
$display("status: %t tip==0", $time);
// slave should have send NACK
$display("status: %t Check for nack", $time);
if(!q[7])
$display("\nERROR: Expected NACK, received ACK\n");
// read data from slave
u0.wb_write(1, CR, 8'h40); // set command (stop)
$display("status: %t generate 'stop'", $time);
// check tip bit
u0.wb_read(1, SR, q);
while(q[1])
u0.wb_read(1, SR, q); // poll it until it is zero
$display("status: %t tip==0", $time);
#250000; // wait 250us
$display("\n\nstatus: %t Testbench done", $time);
$finish;
end
endmodule
module delay (in, out);
input in;
output out;
assign out = in;
specify
(in => out) = (600,600);
endspecify
endmodule
|
