Difference between revisions of "CPUProject"
From ATI public wiki
(Created page with "CPU project is one of the projects designed in department of computer engineering at TTU as a lab project. The main aims of this project are: * Developing a generic CPU witho...") |
|||
Line 4: | Line 4: | ||
* Compiling GCC for this architecture | * Compiling GCC for this architecture | ||
* Booting a light linux on it | * Booting a light linux on it | ||
+ | |||
= CPU Design= | = CPU Design= | ||
+ | |||
== Functionality Requirements == | == Functionality Requirements == | ||
The CPU is supposed to be able to perform the following operations: | The CPU is supposed to be able to perform the following operations: | ||
Line 19: | Line 21: | ||
* NOP/HALT | * NOP/HALT | ||
− | == Instruction Set | + | == Architecture == |
+ | ===Instruction Format=== | ||
+ | Our CPU's instuction has 8 bit of upcode and one operand that can be as long as 32 bit. | ||
+ | First 3 bits of OPcode are at the moment reserved. | ||
+ | |||
+ | == Instruction Set (IS)== | ||
The following instrcutions designed for the CPU: | The following instrcutions designed for the CPU: | ||
{| class="wikitable" | {| class="wikitable" | ||
|- | |- | ||
− | ! Instruction !! | + | ! Instruction !! Register Transfer Language !! OpCode !! DPU Command !! Data To DPU !! MemAddress !! Next PC |
|- | |- | ||
− | | Add_A_B || A <-- A + B || Example || | + | | Add_A_B || A <-- A + B || Example || 00 000 0000 10 || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | Add_A_Mem || | + | | Add_A_Mem || A <-- A + Mem[Operand] || Example || 00 000 0000 00 || ---- || Operand || PC_out+1 |
|- | |- | ||
− | | Add_A_Dir || | + | | Add_A_Dir || A <-- A + Operand || Example || 00 000 0000 01 || Operand || ---- || PC_out+1 |
|- | |- | ||
− | | Sub_A_B || | + | | Sub_A_B || A <-- A - B || Example || 00 000 0001 10 || ---- || ---- || Example |
|- | |- | ||
− | | Sub_A_Mem || | + | | Sub_A_Mem || A <-- A - Mem[Operand] || Example || 00 000 0001 00 || ---- || Operand || PC_out+1 |
|- | |- | ||
− | | Sub_A_Dir || | + | | Sub_A_Dir || A <-- A - Operand || Example || 00 000 0001 01 || Operand || ---- || PC_out+1 |
|- | |- | ||
− | | IncA || | + | | IncA || A <-- A + 1 || Example || 00 000 0000 11 || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | DecA || | + | | DecA || A <-- A - 1 || Example || 00 000 0001 11 || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | And_A_B || | + | | And_A_B || A <-- A and B || Example || 00 000 0100 10 || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | OR_A_B || | + | | OR_A_B || A <-- A or B || Example || 00 000 0101 10 || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | XOR_A_B || | + | | XOR_A_B || A <-- A xor B || Example || 00 000 0110 10 || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | FlipA || | + | | FlipA || A <-- not (A) || Example || 00 000 1100 00 || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | NegA || | + | | NegA || A <-- not(A) + 1 || Example || Example || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | Jmp || | + | | Jmp || PC <-- Operand || Example || Example || ---- || ---- || Depends |
|- | |- | ||
− | | JmpZ || | + | | JmpZ || if Z = 1: PC <-- Operand || Example || Example || ---- || ---- || Depends |
|- | |- | ||
− | | JmpOV || | + | | JmpOV || if OV = 1: PC <-- Operand || Example || Example || ---- || ---- || Depends |
|- | |- | ||
− | | Jmp_rel || | + | | Jmp_rel || PC <-- PC + Operand || Example || Example || ---- || ---- || Depends |
|- | |- | ||
− | | JMPEQ || | + | | JMPEQ || if EQ = 1: PC <-- Operand || Example || Example || ---- || ---- || Depends |
|- | |- | ||
− | | ClearZ || | + | | ClearZ || Z <--- 0 || Example || Example || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | ClearOV || | + | | ClearOV || OV <--- 0 || Example || Example || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | LoadPC || | + | | LoadPC || PC <---- A || Example || Example || ---- || ---- || A |
|- | |- | ||
− | | SavePC || | + | | SavePC || A <---- PC || Example || Example || PC || ---- || PC_out+1 |
|- | |- | ||
− | | ShiftArithR || | + | | ShiftArithR || A <-- A(7) & A(7 downto 1) || Example || Example || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | ShiftArithL || | + | | ShiftArithL || A <-- A(7) & A(5 downto 0)& '0' || Example || Example || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | ShiftA_R || | + | | ShiftA_R || A <-- A(6 downto 0)& '0' || Example || Example || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | ShiftA_L || | + | | ShiftA_L || A <-- '0' & A(7 downto 1) || Example || Example || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | Load_A_Mem || | + | | Load_A_Mem || A <-- Mem[Operand] || Example || Example || ---- || Operand || PC_out+1 |
|- | |- | ||
− | | Store_A_Mem || | + | | Store_A_Mem || Mem[Operand] <-- A || Example || 00 000 0010 -- || ---- || Operand || PC_out+1 |
|- | |- | ||
− | | Load_B_Dir || | + | | Load_B_Dir || B <-- Operand || Example || 00 000 0010 -- || Operand || ---- || PC_out+1 |
|- | |- | ||
− | | Load_B_Mem || | + | | Load_B_Mem || B <-- Mem[Operand] || Example || 00 000 0010 -- || ---- || Operand || PC_out+1 |
|- | |- | ||
− | | JmpC || | + | | JmpC || if C = 1: PC <-- Operand || Example || 00 000 0010 -- || ---- || ---- || Depends |
|- | |- | ||
− | | ClearC || | + | | ClearC || C <--- 0 || Example || 00 000 0010 -- || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | ClearACC || | + | | ClearACC || ACC <-- 0 || Example || Example || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | RRC || | + | | RRC || A <-- C & A(7 downto 1) ,C<-- A(0) || Example || Example || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | | + | | RLC || A <-- A(6 downto 0) & C ,C<-- A(7) || Example || Example || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | | + | | PUSH || Mem [0 + SP] <--- A,SP <--- SP + 1 || Example || 00 000 0010 -- || ---- || SP || PC_out+1 |
|- | |- | ||
− | | | + | | POP || A <--- Mem [0 + SP - 1],SP <--- SP - 1 || Example || Example || ---- || SP - 1 || PC_out+1 |
|- | |- | ||
− | | NOP || | + | | NOP || NOP || Example || 00 000 0010 -- || ---- || ---- || PC_out+1 |
|- | |- | ||
− | | HALT || | + | | HALT || HALT || Example || 00 000 0010 -- || ---- || ---- || PC |
|} | |} | ||
===Other instructions implementation=== | ===Other instructions implementation=== | ||
Line 115: | Line 122: | ||
Add_A_Dir 4 | Add_A_Dir 4 | ||
LoadPC | LoadPC | ||
+ | |||
+ | == DataPath unit== | ||
+ | ===Flags=== | ||
+ | == Control unit== | ||
+ | == Instruction Memory (ROM) == | ||
+ | == Data Memory == | ||
== Functional Testing == | == Functional Testing == |
Revision as of 19:28, 4 December 2014
CPU project is one of the projects designed in department of computer engineering at TTU as a lab project. The main aims of this project are:
- Developing a generic CPU without any fancy feature
- Writing a compiler for it
- Compiling GCC for this architecture
- Booting a light linux on it
Contents
CPU Design
Functionality Requirements
The CPU is supposed to be able to perform the following operations:
- Addition/Subtraction
- Increment/Decrement
- Arithmetic and Logical Shift
- Bitwise AND, OR, XOR and NOT
- Negation
- Load/Store
- Unconditional Branch (jump)
- Branch if zero / Branch if Overflow / Branch if Carry
- Clear Registers/Flags
- PUSH / POP
- NOP/HALT
Architecture
Instruction Format
Our CPU's instuction has 8 bit of upcode and one operand that can be as long as 32 bit. First 3 bits of OPcode are at the moment reserved.
Instruction Set (IS)
The following instrcutions designed for the CPU:
Instruction | Register Transfer Language | OpCode | DPU Command | Data To DPU | MemAddress | Next PC |
---|---|---|---|---|---|---|
Add_A_B | A <-- A + B | Example | 00 000 0000 10 | ---- | ---- | PC_out+1 |
Add_A_Mem | A <-- A + Mem[Operand] | Example | 00 000 0000 00 | ---- | Operand | PC_out+1 |
Add_A_Dir | A <-- A + Operand | Example | 00 000 0000 01 | Operand | ---- | PC_out+1 |
Sub_A_B | A <-- A - B | Example | 00 000 0001 10 | ---- | ---- | Example |
Sub_A_Mem | A <-- A - Mem[Operand] | Example | 00 000 0001 00 | ---- | Operand | PC_out+1 |
Sub_A_Dir | A <-- A - Operand | Example | 00 000 0001 01 | Operand | ---- | PC_out+1 |
IncA | A <-- A + 1 | Example | 00 000 0000 11 | ---- | ---- | PC_out+1 |
DecA | A <-- A - 1 | Example | 00 000 0001 11 | ---- | ---- | PC_out+1 |
And_A_B | A <-- A and B | Example | 00 000 0100 10 | ---- | ---- | PC_out+1 |
OR_A_B | A <-- A or B | Example | 00 000 0101 10 | ---- | ---- | PC_out+1 |
XOR_A_B | A <-- A xor B | Example | 00 000 0110 10 | ---- | ---- | PC_out+1 |
FlipA | A <-- not (A) | Example | 00 000 1100 00 | ---- | ---- | PC_out+1 |
NegA | A <-- not(A) + 1 | Example | Example | ---- | ---- | PC_out+1 |
Jmp | PC <-- Operand | Example | Example | ---- | ---- | Depends |
JmpZ | if Z = 1: PC <-- Operand | Example | Example | ---- | ---- | Depends |
JmpOV | if OV = 1: PC <-- Operand | Example | Example | ---- | ---- | Depends |
Jmp_rel | PC <-- PC + Operand | Example | Example | ---- | ---- | Depends |
JMPEQ | if EQ = 1: PC <-- Operand | Example | Example | ---- | ---- | Depends |
ClearZ | Z <--- 0 | Example | Example | ---- | ---- | PC_out+1 |
ClearOV | OV <--- 0 | Example | Example | ---- | ---- | PC_out+1 |
LoadPC | PC <---- A | Example | Example | ---- | ---- | A |
SavePC | A <---- PC | Example | Example | PC | ---- | PC_out+1 |
ShiftArithR | A <-- A(7) & A(7 downto 1) | Example | Example | ---- | ---- | PC_out+1 |
ShiftArithL | A <-- A(7) & A(5 downto 0)& '0' | Example | Example | ---- | ---- | PC_out+1 |
ShiftA_R | A <-- A(6 downto 0)& '0' | Example | Example | ---- | ---- | PC_out+1 |
ShiftA_L | A <-- '0' & A(7 downto 1) | Example | Example | ---- | ---- | PC_out+1 |
Load_A_Mem | A <-- Mem[Operand] | Example | Example | ---- | Operand | PC_out+1 |
Store_A_Mem | Mem[Operand] <-- A | Example | 00 000 0010 -- | ---- | Operand | PC_out+1 |
Load_B_Dir | B <-- Operand | Example | 00 000 0010 -- | Operand | ---- | PC_out+1 |
Load_B_Mem | B <-- Mem[Operand] | Example | 00 000 0010 -- | ---- | Operand | PC_out+1 |
JmpC | if C = 1: PC <-- Operand | Example | 00 000 0010 -- | ---- | ---- | Depends |
ClearC | C <--- 0 | Example | 00 000 0010 -- | ---- | ---- | PC_out+1 |
ClearACC | ACC <-- 0 | Example | Example | ---- | ---- | PC_out+1 |
RRC | A <-- C & A(7 downto 1) ,C<-- A(0) | Example | Example | ---- | ---- | PC_out+1 |
RLC | A <-- A(6 downto 0) & C ,C<-- A(7) | Example | Example | ---- | ---- | PC_out+1 |
PUSH | Mem [0 + SP] <--- A,SP <--- SP + 1 | Example | 00 000 0010 -- | ---- | SP | PC_out+1 |
POP | A <--- Mem [0 + SP - 1],SP <--- SP - 1 | Example | Example | ---- | SP - 1 | PC_out+1 |
NOP | NOP | Example | 00 000 0010 -- | ---- | ---- | PC_out+1 |
HALT | HALT | Example | 00 000 0010 -- | ---- | ---- | PC |
Other instructions implementation
the follwoing instructions can be also implemented with the ones in IS:
- Call "function_name":
PUSH SavePC Push Jmp "function address" POP
- Return:
POP Add_A_Dir 4 LoadPC