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Improved register file addressing and printout

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This commit is contained in:
(Tim) Efthimis Kritikos 2023-02-11 13:41:12 +00:00
parent abe263aa57
commit be06244021
2 changed files with 115 additions and 40 deletions
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89
cpu/processor.v
View File

@ -36,9 +36,8 @@ always @(negedge reset) begin
state=`PROC_HALT_STATE;
ProgCount=0;//TODO: Reset Vector
HALT=0;
reg_read=1;
reg_write=1;
reg_read_read=1;
reg_write_we=1;
reg_read_oe=1;
unaligned_access=0;
ALU_OUT=1;
@(posedge reset)
@ -50,16 +49,13 @@ end
/*** ALU and EXEC stage logic ***/
//Architectural Register file
reg [2:0] reg_addr;
reg [15:0] reg_data;
reg reg_read;
reg reg_write;
reg [2:0] reg_read_addr;
reg [3:0] reg_write_addr;
reg [15:0] reg_write_data;
reg reg_write_we;
reg [3:0] reg_read_addr;
reg [15:0] reg_read_data;
reg reg_read_read;
wire [15:0] reg_data_;
assign reg_data_=reg_data;
register_file register_file(reg_addr,reg_data_,reg_read,reg_write,reg_read_addr,reg_read_data,reg_read_read);
reg reg_read_oe;
register_file register_file(reg_write_addr,reg_write_data,reg_write_we,reg_read_addr,reg_read_data,reg_read_oe);
//ALU
mux4 #(.WIDTH(16)) MUX16_1A(
@ -109,7 +105,7 @@ always @(negedge clock) begin
`PROC_EX_STATE_EXIT:begin
case(out_sel)
2'b11:begin
reg_write=0;
reg_write_we=0;
state=`PROC_IF_STATE_ENTRY;
end
default:begin
@ -133,8 +129,8 @@ always @(posedge clock) begin
external_address_bus <= ProgCount;
read <= 0;
write <= 1;
reg_read_read=1;
reg_write=1;
reg_read_oe=1;
reg_write_we=1;
ALU_OUT=1;
state=`PROC_IF_WRITE_CIR;
end
@ -142,21 +138,28 @@ always @(posedge clock) begin
external_address_bus <= ProgCount;
state=`PROC_IF_STATE_EXTRA_FETCH;
end
/* AFTER THE IF STAGE WE HAVE THE FRIST BYTE OF THE
* INSTRUCTION ADN THE ONE FOLLOWING, ALLIGNED CORRECTLY TO
* CIR */
`PROC_DE_STATE_ENTRY:begin
case(CIR[15:10])
6'b000001 : begin
/* ADD, ... */
if ( CIR[9:9] == 0 )begin
/* Add Immediate to accumulator */
/* Add Immediate word/byte to accumulator */
unaligned_access=~unaligned_access;
in1_sel=2'b00;
in2_sel=2'b01;
out_sel=2'b11;
reg_read_addr=3'b000;
reg_addr=3'b000;
reg_read_read=0;
reg_read_addr={CIR[8:8],3'b000};
reg_write_addr={CIR[8:8],3'b000};
reg_read_oe=0;
ALU_OUT=0;
state=`PROC_DE_LOAD_16_PARAM;
if(CIR[8:8]==1)
state=`PROC_DE_LOAD_16_PARAM;
else begin
`invalid_instruction /*do 8bit loads*/
end
end else begin
`invalid_instruction
end
@ -165,7 +168,7 @@ always @(posedge clock) begin
/* ADD, ADC, SUB, SBB, CMP , AND, ... */
case (CIR[5:3])
3'b000 : begin
/* Add Immediate to register/memory */
/* Add Immediate word/byte to register/memory */
if(unaligned_access==0)begin
ProgCount=ProgCount+1;
external_address_bus <= ProgCount;
@ -173,11 +176,16 @@ always @(posedge clock) begin
in1_sel=2'b00;
in2_sel=2'b01;
out_sel=CIR[7:6];
reg_read_addr=CIR[2:0];
reg_addr=CIR[2:0];
reg_read_read=0;
reg_read_addr={CIR[8:8],CIR[2:0]};
reg_write_addr={CIR[8:8],CIR[2:0]};
reg_read_oe=0;
ALU_OUT=0;
state=`PROC_DE_LOAD_16_PARAM;
if(CIR[8:8]==1)
state=`PROC_DE_LOAD_16_PARAM;
else begin
`invalid_instruction /*do 8bit loads*/
end
end
default:begin
`invalid_instruction
@ -185,15 +193,30 @@ always @(posedge clock) begin
endcase
end
6'b101100,
6'b101101,
6'b101110,
6'b101111 : begin
/*Move Immediate to register*/
6'b101101:begin
/*Move Immediate byte to register*/
if(unaligned_access==0)begin
ProgCount=ProgCount+1;
external_address_bus <= ProgCount;
end
unaligned_access=~unaligned_access;
in1_sel=2'b00;
in2_sel=2'b00;
out_sel=2'b11;
reg_addr=CIR[10:8];
reg_write_addr={1'b0,CIR[10:8]};
PARAM1[7:0]=CIR[7:0];
PARAM2=0;
ALU_OUT=0;
state=`PROC_EX_STATE_ENTRY;
end
6'b101110,
6'b101111 : begin
/*Move Immediate word to register*/
unaligned_access=~unaligned_access;
in1_sel=2'b00;
in2_sel=2'b00;
out_sel=2'b11;
reg_write_addr={1'b1,CIR[10:8]};
ALU_OUT=0;
PARAM2=0;
state=`PROC_DE_LOAD_16_PARAM;
@ -212,9 +235,9 @@ always @(posedge clock) begin
in2_sel=2'b01;
out_sel=CIR[7:6];
PARAM1=1;
reg_read_addr=CIR[2:0];
reg_addr=CIR[2:0];
reg_read_read=0;
reg_read_addr={1'b0,CIR[2:0]};
reg_write_addr={1'b0,CIR[2:0]};
reg_read_oe=0;
ALU_OUT=0;
state=`PROC_EX_STATE_ENTRY;
end
@ -263,7 +286,7 @@ always @(posedge clock) begin
state=`PROC_EX_STATE_ENTRY;
end
`PROC_EX_STATE_ENTRY:begin
reg_data=ADDER16_1O;
reg_write_data=ADDER16_1O;
state=`PROC_EX_STATE_EXIT;
ERROR=0;
end

66
cpu/registers.v
View File

@ -1,10 +1,62 @@
module register_file ( input [2:0]addr1, inout [15:0]data1, input wire read1, input wire write1 ,input [2:0]addr2,output [15:0]data2,input wire read2);
/* Register address fromat:
* [W-bit] [ 3-bit address] */
module register_file (write_port1_addr,write_port1_data,write_port1_we,read_port1_addr,read_port1_data,read_port1_oe);
input [3:0] write_port1_addr,read_port1_addr;
input [15:0] write_port1_data;
output [15:0] read_port1_data;
input read_port1_oe;
input write_port1_we;
reg [15:0] registers [7:0];
assign data2 = !read2 ? registers[addr2] : 'hz;
assign data1 = !read1 ? registers[addr1] : 'hz;
always @(negedge write1) begin
registers[addr1] = data1;
//$display("registers: 0:%04x 1:%04x 2:%04x",registers[0],registers[1],registers[2]);
$display("register %d update to %04x (data bus %04x)",addr1,registers[addr1],data1);
assign read_port1_data = !read_port1_oe ?
( read_port1_addr[3:3] ? registers[read_port1_addr[2:0]] :
( read_port1_addr[2:2] ? {8'b0,registers[read_port1_addr[2:0]][15:8]} : {8'b0,registers[read_port1_addr[2:0]][7:0]} ) ) : 'hz;
`define DEBUG_REG_WRITES
`ifdef DEBUG_REG_WRITES
string debug_name;
logic[15:0] debug_value;
`endif
always @(negedge write_port1_we) begin
if(write_port1_addr[3:3]==1)begin
/* Word : AX,CX,DX,BX,SP,BP,SI,DI */
registers[write_port1_addr[2:0]]=write_port1_data;
end else begin
/* Byte : AL,CL,DL,BL,AX,CX,DX,BX */
if(write_port1_addr[2:2]==1)begin
/* Byte */
registers[write_port1_addr[2:0]][15:8]=write_port1_data[7:0];
end else begin
/* Byte */
registers[write_port1_addr[2:0]][7:0]=write_port1_data[7:0];
end
end
`ifdef DEBUG_REG_WRITES
if(write_port1_addr[3:2]==2'b11)begin
case(write_port1_addr[1:0])
2'b00: debug_name="sp";
2'b01: debug_name="bp";
2'b10: debug_name="si";
2'b11: debug_name="di";
endcase
debug_value=registers[write_port1_addr[2:0]];
end else begin
case(write_port1_addr[1:0])
2'b00: debug_name="ax";
2'b01: debug_name="cx";
2'b10: debug_name="dx";
2'b11: debug_name="bx";
endcase
debug_value=registers[write_port1_addr[2:0]];
end
$display("register %%%s update to $0x%04x",debug_name,debug_value);
`endif
end
endmodule