在 always_ff @ 中交换 2 个参数
Swapping 2 parameters in always_ff @
我的代码有问题。
我正在尝试在同一时钟的 Xspeed 和 Yspeed 之间切换，而 if 语句为真。
我遇到错误：
cant resolve multiple constant drivers for net
和
constant drivers at module_name
几个 if 语句显示相同的错误。
int Xspeed, topLeftX_FixedPoint; // local parameters
int Yspeed, topLeftY_FixedPoint;
//////////--------------------------------------------------------------------------------------------------------------=
// calculation 0f Y Axis speed using gravity or colision
always_ff@(posedge clk or negedge resetN)
begin
if(!resetN) begin
Yspeed <= INITIAL_Y_SPEED;
topLeftY_FixedPoint <= INITIAL_Y * FIXED_POINT_MULTIPLIER;
end
else begin
// colision Calcultaion
//hit bit map has one bit per edge: Left-Top-Right-Bottom
if ((collision && HitEdgeCode [2] == 1 && HitEdgeCode[1]==1)) begin // hit top border of brick
if (Yspeed < 0 && Xspeed > 0) begin // while moving up and moving right
Yspeed <= Xspeed ;
Xspeed <= Yspeed ; // negative move left
end
end
完整代码：
// (c) Technion IIT, Department of Electrical Engineering 2021
//-- Alex Grinshpun Apr 2017
//-- Dudy Nov 13 2017
// SystemVerilog version Alex Grinshpun May 2018
// coding convention dudy December 2018
// updaed Eyal Lev Feb 2021
module pokadoor_moveCollision (
input logic clk,
input logic resetN,
input logic startOfFrame, // short pulse every start of frame 30Hz
input logic Y_direction, //change the direction in Y to up
input logic toggleX, //toggle the X direction
input logic collision, //collision if smiley hits an object
input logic [3:0] HitEdgeCode, //one bit per edge
output logic signed [10:0] topLeftX, // output the top left corner
output logic signed [10:0] topLeftY // can be negative , if the object is partliy outside
);
// a module used to generate the ball trajectory.
parameter int INITIAL_X = 320;
parameter int INITIAL_Y = 240;
parameter int INITIAL_X_SPEED = 60;
parameter int INITIAL_Y_SPEED = 150;
parameter int MAX_Y_SPEED = 230;
const int Y_ACCEL = -1;
const int FIXED_POINT_MULTIPLIER = 64;
// FIXED_POINT_MULTIPLIER is used to enable working with integers in high resolution so that
// we do all calculations with topLeftX_FixedPoint to get a resolution of 1/64 pixel in calcuatuions,
// we devide at the end by FIXED_POINT_MULTIPLIER which must be 2^n, to return to the initial proportions
const int x_FRAME_SIZE = 639 * FIXED_POINT_MULTIPLIER; // note it must be 2^n
const int y_FRAME_SIZE = 479 * FIXED_POINT_MULTIPLIER;
const int bracketOffset = 30;
const int OBJECT_WIDTH_X = 64;
int Xspeed, topLeftX_FixedPoint; // local parameters
int temp;
int Yspeed, topLeftY_FixedPoint;
//////////--------------------------------------------------------------------------------------------------------------=
// calculation 0f Y Axis speed using gravity or colision
always_ff@(posedge clk or negedge resetN)
begin
if(!resetN) begin
Yspeed <= INITIAL_Y_SPEED;
topLeftY_FixedPoint <= INITIAL_Y * FIXED_POINT_MULTIPLIER;
end
else begin
// colision Calcultaion
//hit bit map has one bit per edge: Left-Top-Right-Bottom
if ((collision && HitEdgeCode [2] == 1 && HitEdgeCode[1]==1)) begin // hit top border of brick
if (Yspeed < 0 && Xspeed > 0) begin // while moving up and moving right
Yspeed <= Xspeed ;
Xspeed <= Yspeed ; // negative move left
end
end
if ((collision && HitEdgeCode [2] == 1 && HitEdgeCode[3]==1)) begin // hit top border of brick
if (Yspeed < 0 && Xspeed < 0) begin // while moving up and moving left
Yspeed <= -Xspeed ;
Xspeed <= -Yspeed ; // negative move left
end
end
if ((collision && HitEdgeCode [2] == 1 && HitEdgeCode[3]==0 && HitEdgeCode[1]==0)) begin // hit top border of brick
if (Yspeed < 0) begin// while moving up
Yspeed <= -Yspeed ;
end
end
////
if ((collision && HitEdgeCode [0] == 1 && HitEdgeCode[1]==1)) begin// || (collision && HitEdgeCode [1] == 1 )) hit bottom border of brick
if (Yspeed > 0 && Xspeed > 0) begin// while moving down and moving right
Yspeed <= -Xspeed ;
Xspeed <= -Yspeed ;
end
end
if ((collision && HitEdgeCode [0] == 1 && HitEdgeCode[3]==1)) begin// || (collision && HitEdgeCode [1] == 1 )) hit bottom border of brick
if (Yspeed > 0 && Xspeed < 0) begin// while moving down and moving left
Yspeed <= Xspeed ;
Xspeed <= Yspeed ;
end
end
if ((collision && HitEdgeCode [0] == 1 && HitEdgeCode[3]==0 && HitEdgeCode[1]==0 )) begin// || (collision && HitEdgeCode [1] == 1 )) hit bottom border of brick
if (Yspeed > 0 ) begin// while moving down
Yspeed <= -Yspeed ;
end
end
// perform position and speed integral only 30 times per second
if (startOfFrame == 1'b1) begin
topLeftY_FixedPoint <= topLeftY_FixedPoint + Yspeed; // position interpolation
if (Yspeed < MAX_Y_SPEED ) // limit the spped while going down
Yspeed <= Yspeed - Y_ACCEL ; // deAccelerate : slow the speed down every clock tick
if (Y_direction) begin // button was pushed to go upwards
if (Yspeed > 0 ) // while moving down
Yspeed <= -Yspeed ; // change speed to go up
end ;
end
end
end
//////////--------------------------------------------------------------------------------------------------------------=
// calculation of X Axis speed using and position calculate regarding X_direction key or colision
always_ff@(posedge clk or negedge resetN)
begin
if(!resetN)
begin
Xspeed <= INITIAL_X_SPEED;
topLeftX_FixedPoint <= INITIAL_X * FIXED_POINT_MULTIPLIER;
end
else begin
// an edge input is tested here as it is a very short instance
//if (toggleX)
//Xspeed <= -Xspeed;
// collisions with the sides
if (collision && HitEdgeCode [3] == 1 && HitEdgeCode[0] ==0 && HitEdgeCode[2]==0) begin
if (Xspeed < 0 ) // while moving left
Xspeed <= -Xspeed ; // positive move right
end
if (collision && HitEdgeCode [1] == 1 && HitEdgeCode[0] ==0 && HitEdgeCode[2]==0 ) begin // hit right border of brick
if (Xspeed > 0 ) // while moving right
Xspeed <= -Xspeed ; // negative move left
end
if (startOfFrame == 1'b1 )//&& Yspeed != 0)
topLeftX_FixedPoint <= topLeftX_FixedPoint + Xspeed;
end
end
//get a better (64 times) resolution using integer
assign topLeftX = topLeftX_FixedPoint / FIXED_POINT_MULTIPLIER ; // note it must be 2^n
assign topLeftY = topLeftY_FixedPoint / FIXED_POINT_MULTIPLIER ;
endmodule
错误：
Error (10028): Can't resolve multiple constant drivers for net
"Xspeed[31]" at pokadoor_moveCollision.sv(139) Error (10029): Constant
driver at pokadoor_moveCollision.sv(62) Error (10028): Can't resolve
multiple constant drivers for net "Xspeed[30]" at
pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple
constant drivers for net "Xspeed[29]" at
pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple
constant drivers for net "Xspeed[28]" at
pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple
constant drivers for net "Xspeed[27]" at
pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple
constant drivers for net "Xspeed[26]" at
pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple
constant drivers for net "Xspeed[25]" at
pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple
constant drivers for net "Xspeed[24]" at
pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple
constant drivers for net "Xspeed[23]" at
pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple
constant drivers for net "Xspeed[22]" at
pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple
constant drivers for net "Xspeed[21]" at
pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple
constant drivers for net "Xspeed[20]" at
pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple
constant drivers for net "Xspeed[19]" at
pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple
constant drivers for net "Xspeed[18]" at
pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple
constant drivers for net "Xspeed[17]" at
pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple
constant drivers for net "Xspeed[16]" at
pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple
constant drivers for net "Xspeed[15]" at
pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple
constant drivers for net "Xspeed[14]" at
pokadoor_moveCollision.sv(139) Error (12152): Can't elaborate user
hierarchy "Pokadoor_Block_bdf:inst14|pokadoor_moveCollision:inst"
Error: Quartus Prime Analysis & Elaboration was unsuccessful. 20
errors, 15 warnings Error: Peak virtual memory: 4797 megabytes
Error: Processing ended: Thu Apr 14 14:26:35 2022 Error: Elapsed
time: 00:00:07 Error: Total CPU time (on all processors): 00:00:16
这些错误消息不是很具体。您可以从其他模拟器获得更多有用的消息，例如 edaplayground（Cadence 和 Synopsys）上的模拟器。
问题是您不能分配给来自不同 always_ff 块的相同信号。例如，您的代码从两个 always_ff 块分配给 Xspeed。
参考 IEEE Std 1800-2017，第 9.2.2.4 节顺序逻辑always_ff程序：
Variables on the left-hand side of assignments within an always_ff
procedure, including variables from the contents of a called function,
shall not be written to by any other process.
您必须重组您的代码，以便对 Xspeed 的所有赋值都在同一个 always_ff 块中完成。
我的代码有问题。
我正在尝试在同一时钟的 Xspeed 和 Yspeed 之间切换，而 if 语句为真。
我遇到错误：
cant resolve multiple constant drivers for net
和
constant drivers at module_name
几个 if 语句显示相同的错误。
int Xspeed, topLeftX_FixedPoint; // local parameters
int Yspeed, topLeftY_FixedPoint;
//////////--------------------------------------------------------------------------------------------------------------=
// calculation 0f Y Axis speed using gravity or colision
always_ff@(posedge clk or negedge resetN)
begin
if(!resetN) begin
Yspeed <= INITIAL_Y_SPEED;
topLeftY_FixedPoint <= INITIAL_Y * FIXED_POINT_MULTIPLIER;
end
else begin
// colision Calcultaion
//hit bit map has one bit per edge: Left-Top-Right-Bottom
if ((collision && HitEdgeCode [2] == 1 && HitEdgeCode[1]==1)) begin // hit top border of brick
if (Yspeed < 0 && Xspeed > 0) begin // while moving up and moving right
Yspeed <= Xspeed ;
Xspeed <= Yspeed ; // negative move left
end
end
完整代码：
// (c) Technion IIT, Department of Electrical Engineering 2021
//-- Alex Grinshpun Apr 2017
//-- Dudy Nov 13 2017
// SystemVerilog version Alex Grinshpun May 2018
// coding convention dudy December 2018
// updaed Eyal Lev Feb 2021
module pokadoor_moveCollision (
input logic clk,
input logic resetN,
input logic startOfFrame, // short pulse every start of frame 30Hz
input logic Y_direction, //change the direction in Y to up
input logic toggleX, //toggle the X direction
input logic collision, //collision if smiley hits an object
input logic [3:0] HitEdgeCode, //one bit per edge
output logic signed [10:0] topLeftX, // output the top left corner
output logic signed [10:0] topLeftY // can be negative , if the object is partliy outside
);
// a module used to generate the ball trajectory.
parameter int INITIAL_X = 320;
parameter int INITIAL_Y = 240;
parameter int INITIAL_X_SPEED = 60;
parameter int INITIAL_Y_SPEED = 150;
parameter int MAX_Y_SPEED = 230;
const int Y_ACCEL = -1;
const int FIXED_POINT_MULTIPLIER = 64;
// FIXED_POINT_MULTIPLIER is used to enable working with integers in high resolution so that
// we do all calculations with topLeftX_FixedPoint to get a resolution of 1/64 pixel in calcuatuions,
// we devide at the end by FIXED_POINT_MULTIPLIER which must be 2^n, to return to the initial proportions
const int x_FRAME_SIZE = 639 * FIXED_POINT_MULTIPLIER; // note it must be 2^n
const int y_FRAME_SIZE = 479 * FIXED_POINT_MULTIPLIER;
const int bracketOffset = 30;
const int OBJECT_WIDTH_X = 64;
int Xspeed, topLeftX_FixedPoint; // local parameters
int temp;
int Yspeed, topLeftY_FixedPoint;
//////////--------------------------------------------------------------------------------------------------------------=
// calculation 0f Y Axis speed using gravity or colision
always_ff@(posedge clk or negedge resetN)
begin
if(!resetN) begin
Yspeed <= INITIAL_Y_SPEED;
topLeftY_FixedPoint <= INITIAL_Y * FIXED_POINT_MULTIPLIER;
end
else begin
// colision Calcultaion
//hit bit map has one bit per edge: Left-Top-Right-Bottom
if ((collision && HitEdgeCode [2] == 1 && HitEdgeCode[1]==1)) begin // hit top border of brick
if (Yspeed < 0 && Xspeed > 0) begin // while moving up and moving right
Yspeed <= Xspeed ;
Xspeed <= Yspeed ; // negative move left
end
end
if ((collision && HitEdgeCode [2] == 1 && HitEdgeCode[3]==1)) begin // hit top border of brick
if (Yspeed < 0 && Xspeed < 0) begin // while moving up and moving left
Yspeed <= -Xspeed ;
Xspeed <= -Yspeed ; // negative move left
end
end
if ((collision && HitEdgeCode [2] == 1 && HitEdgeCode[3]==0 && HitEdgeCode[1]==0)) begin // hit top border of brick
if (Yspeed < 0) begin// while moving up
Yspeed <= -Yspeed ;
end
end
////
if ((collision && HitEdgeCode [0] == 1 && HitEdgeCode[1]==1)) begin// || (collision && HitEdgeCode [1] == 1 )) hit bottom border of brick
if (Yspeed > 0 && Xspeed > 0) begin// while moving down and moving right
Yspeed <= -Xspeed ;
Xspeed <= -Yspeed ;
end
end
if ((collision && HitEdgeCode [0] == 1 && HitEdgeCode[3]==1)) begin// || (collision && HitEdgeCode [1] == 1 )) hit bottom border of brick
if (Yspeed > 0 && Xspeed < 0) begin// while moving down and moving left
Yspeed <= Xspeed ;
Xspeed <= Yspeed ;
end
end
if ((collision && HitEdgeCode [0] == 1 && HitEdgeCode[3]==0 && HitEdgeCode[1]==0 )) begin// || (collision && HitEdgeCode [1] == 1 )) hit bottom border of brick
if (Yspeed > 0 ) begin// while moving down
Yspeed <= -Yspeed ;
end
end
// perform position and speed integral only 30 times per second
if (startOfFrame == 1'b1) begin
topLeftY_FixedPoint <= topLeftY_FixedPoint + Yspeed; // position interpolation
if (Yspeed < MAX_Y_SPEED ) // limit the spped while going down
Yspeed <= Yspeed - Y_ACCEL ; // deAccelerate : slow the speed down every clock tick
if (Y_direction) begin // button was pushed to go upwards
if (Yspeed > 0 ) // while moving down
Yspeed <= -Yspeed ; // change speed to go up
end ;
end
end
end
//////////--------------------------------------------------------------------------------------------------------------=
// calculation of X Axis speed using and position calculate regarding X_direction key or colision
always_ff@(posedge clk or negedge resetN)
begin
if(!resetN)
begin
Xspeed <= INITIAL_X_SPEED;
topLeftX_FixedPoint <= INITIAL_X * FIXED_POINT_MULTIPLIER;
end
else begin
// an edge input is tested here as it is a very short instance
//if (toggleX)
//Xspeed <= -Xspeed;
// collisions with the sides
if (collision && HitEdgeCode [3] == 1 && HitEdgeCode[0] ==0 && HitEdgeCode[2]==0) begin
if (Xspeed < 0 ) // while moving left
Xspeed <= -Xspeed ; // positive move right
end
if (collision && HitEdgeCode [1] == 1 && HitEdgeCode[0] ==0 && HitEdgeCode[2]==0 ) begin // hit right border of brick
if (Xspeed > 0 ) // while moving right
Xspeed <= -Xspeed ; // negative move left
end
if (startOfFrame == 1'b1 )//&& Yspeed != 0)
topLeftX_FixedPoint <= topLeftX_FixedPoint + Xspeed;
end
end
//get a better (64 times) resolution using integer
assign topLeftX = topLeftX_FixedPoint / FIXED_POINT_MULTIPLIER ; // note it must be 2^n
assign topLeftY = topLeftY_FixedPoint / FIXED_POINT_MULTIPLIER ;
endmodule
错误：
Error (10028): Can't resolve multiple constant drivers for net "Xspeed[31]" at pokadoor_moveCollision.sv(139) Error (10029): Constant driver at pokadoor_moveCollision.sv(62) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[30]" at pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[29]" at pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[28]" at pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[27]" at pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[26]" at pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[25]" at pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[24]" at pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[23]" at pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[22]" at pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[21]" at pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[20]" at pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[19]" at pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[18]" at pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[17]" at pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[16]" at pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[15]" at pokadoor_moveCollision.sv(139) Error (10028): Can't resolve multiple constant drivers for net "Xspeed[14]" at pokadoor_moveCollision.sv(139) Error (12152): Can't elaborate user hierarchy "Pokadoor_Block_bdf:inst14|pokadoor_moveCollision:inst" Error: Quartus Prime Analysis & Elaboration was unsuccessful. 20 errors, 15 warnings Error: Peak virtual memory: 4797 megabytes Error: Processing ended: Thu Apr 14 14:26:35 2022 Error: Elapsed time: 00:00:07 Error: Total CPU time (on all processors): 00:00:16
这些错误消息不是很具体。您可以从其他模拟器获得更多有用的消息，例如 edaplayground（Cadence 和 Synopsys）上的模拟器。
问题是您不能分配给来自不同 always_ff 块的相同信号。例如，您的代码从两个 always_ff 块分配给 Xspeed。
参考 IEEE Std 1800-2017，第 9.2.2.4 节顺序逻辑always_ff程序：
Variables on the left-hand side of assignments within an always_ff procedure, including variables from the contents of a called function, shall not be written to by any other process.
您必须重组您的代码，以便对 Xspeed 的所有赋值都在同一个 always_ff 块中完成。