Execution time is limited to 1000ms.
				
Information

				

					C15 is a 32-bit, 100 MHz softcore microprocessor synthesized using an FPGA. The processor contains three registers, all 32 bits wide: register A, register B, and register R, which are used for arithmetic operations. There are four flags: zero, greater than, less than, and out of time (indicating the exhaustion of the execution time).

					

Press "Run" to assemble/compile, upload, and execute the machine code. You can program the processor by either using C15 assembly or the C programming language.
				

				
				
Using the C Compiler

				

					To use the C compiler, click on the  button and add .c to end of your filename.
					The compiler has support for struct, array and 32-bit primitive data types: uint, int, and float.
					There is currently no support for recursion due to the limited stack space in the processor. 
					
					


					
					There are a few intrinsics provided:
					

					
					Try out these sample files by clicking on the links to load them into the editor:

					
				

				
				
Using the C15 Assembler

				

					To use the assembler, click on the  button and add .asm to end of your filename. Additionally, you can view the disassembly of C files by clicking on the View Disassembly button.


					
					Instructions are 32-bits in size, except for STORE and STOREPUSH, which are 64-bits in size. Opcodes are 8-bits in size. Arguments/operands are 12-bits in size, except for the immediate values of STORE and STOREPUSH.
					
					 
				

			

		


		

			

				
HALT

				
Halts the execution of the processor.

			

			

				
SAVE ADDRESS

				
Saves the value in register R to the given address.

			

			

				
SAVEA ADDRESS

				
Saves the value in register A to the given address.

			

			

				
SAVEB ADDRESS

				
Saves the value in register B to the given address.

			

			

				
SAVEPUSH

				
Pushes the value in register R to the top of the general-purpose stack.

			

			

				
SAVETOA

				
Saves the value in register R to register A.

			

			

				
SAVETOB

				
Saves the value in register R to register B.

			

			

				
STORE VALUE ADDRESS

				
Writes the given immediate value to the address.

				The given immediate value is 32-bits in size.
			

			

				
STOREPUSH VALUE

				
Pushes the given immediate value to the top of the general-purpose stack.

				The given immediate value is 32-bits in size.
			

			

				
QSTORE VALUE ADDRESS

				
Writes the given immediate value to the given address.

			
	
			

				
GETA ADDRESS

				
Loads the value located at the given address into register A.

			

			

				
GETB ADDRESS

				
Loads the value located at the given address into register B.

			

			

				
GETAVB ADDRESS VALUE

				
Loads the value located at the given address into register A and loads the given immediate value into register B.

			

			

				
GETPOPA

				
Pops the value at the top of the general-purpose stack and saves it into register A.

			

			

				
GETPOPB

				
Pops the value at the top of the general-purpose stack and saves it into register B.

			

			

				
GETPOPR

				
Pops the value at the top of the general-purpose stack and saves it into register R.

			

			

				
VGETA VALUE

				
Loads the given immediate value into register A.

			

			

				
VGETB VALUE

				
Loads the given immediate value into register B.

			

			

				
VPUSH VALUE

				
Pushes the given immediate value to the top of the general-purpose stack.

			

			

				
PUSH ADDRESS

				
Pushes the value at the given address to the top of the general-purpose stack.

			

			

				
POP ADDRESS

				
Pops the value from the top of the general-purpose stack and saves it at the given address.

			

			

				
POPNOP

				
Pops the value from the top of the general-purpose stack and discards it.

			

			

				
SWAP

				
Swaps the values of register A and B.

			

			

				
SETLED

				
Sets the on-board 8-bit LEDs to represent the value in register A.

			

			

				
RAND

				
Generates a 32-bit random number and places the random number into register A.

			

			

				
TICK

				
Places the number of clock cycles since execution began into register R.

			

			

				
NOP

				
Performs no operation.

			

			

				
CALL ADDRESS

				
Pushes the next address after the current address to the call stack and jumps to the given address.

			

			

				
RCALL ADDRESS

				
Pushes the next address after the current address to the call stack and jumps to the address located at the given address.

			

			

				
RTN

				
Pops the address at top of the call stack and jumps to it.

			
 
			

				
JMP ADDRESS

				
Jumps to the given address (sets the program counter to the given address).

			

			

				
JA ADDRESS

				
Jumps to the given address if the value in register R is non-zero.

			

			

				
JNA ADDRESS

				
Jumps to the given address if the value in register R is zero.

			

			

				
JZ ADDRESS

				
Jumps to the given address if the zero flag is set to 1.

			

			

				
JNZ ADDRESS

				
Jumps to the given address if the zero flag is set to 0.

			

			

				
JLT ADDRESS

				
Jumps to the given address if the less than flag is set to 1.

			

			

				
JLTE ADDRESS

				
Jumps to the given address if the greater than flag is set to 0.

			

			

				
JGT ADDRESS

				
Jumps to the given address if the greater than flag is set to 1.

			

			

				
JGTE ADDRESS

				
Jumps to the given address if the less than flag is set to 0.

			

			

				
MOV SOURCE DESTINATION

				
Copies the value from the source address to the destination address.

			

			

				
MOVIN SOURCE

				
Copies the value from the source address to the destination address defined in register R.

			

			

				
MOVINPOP

				
Pops the source address from the top of the stack and copies the value from the source address to the destination address defined in register R.

			

			

				
MOVOUT DESTINATION

				
Copies the value located at the source address defined in register R to the destination address.

			

			

				
MOVOUTPUSH

				
Pushes the value located at the source address defined in register R to the top stack.

			

			

				
LAND

				
If the value in register A and register B are non-zero, then 1 is saved into register R, otherwise 0 is saved into register R.

			

			

				
LOR

				
If the value in register A or register B (or both) are non-zero, then 1 is saved into register R, otherwise 0 is saved into register R.

			

			

				
NOT

				
Performs bitwise NOT on the value in register A and saves the result into register R. (~A)

			

			

				
AND

				
Performs bitwise AND on the values in register A and register B and saves the result into register R. (A & B)

			

			

				
OR

				
Performs bitwise OR on the values in register A and register B and saves the result into register R. (A | B)

			

			

				
XOR

				
Performs bitwise XOR on the values in register A and register B and saves the result into register R. (A ^ B)

			

			

				
SHIFTL

				
Left shifts the value in register A by the value in register B and saves the result into register R. (A << B)

			

			

				
SHIFTR

				
Right shifts the value in register A by the value in register B and saves the result into register R. (A >> B)

			

			

				
FLTOINT

				
Converts a single-precision floating-point in register A to an integer and places the result in register R. (int)A

			

			

				
INTTOFL

				
Converts an integer in register A to a single-precision floating-point and places the result in register R. (float)A

			

			

				
INC

				
SINC

				
FINC

				
Increments the value of register A and saves the result back into register A. (A++)

			

			

				
DEC

				
SDEC

				
FDEC

				
Decrements the value of register A and saves the result back into register A. (A--)

			

			

				
ADD

				
SADD

				
FADD

				
Sums the values in register A and B and saves the result in register R. (A + B)

				For unsigned/signed addition, the zero flag will be set to 1 if the result is zero (which may occur because of an arithmetic overflow).
			

			

				
SUB

				
SSUB

				
FSUB

				
Subtracts the values in register A and B and saves the result in register R. (A - B)

				For unsigned/signed substraction, the zero flag will be set to 1 if the result is zero (which may occur because of an arithmetic underflow).
			

			

				
MULT

				
SMULT

				
FMULT

				
Multiplies the values in register A and B and saves the result in register R. (A × B)

				For unsigned/signed multiplication, the zero flag will be set to 1 if the result is zero.
			

			

				
DIV

				
SDIV

				
FDIV

				
Divides the values in register A and B and saves the quotient in register R. (A ÷ B)

				For unsigned/signed division, the zero flag will be set to 1 if the result is zero.
			

			

				
REM

				
SREM

				
Divides the values in register A and B and saves the remainder in register R. (A % B)

			

			

				
CMP

				
Compares the values in registers A and B and sets the following flags:
					

				

			

			

				
CMPLT

				
SCMPLT

				
FCMPLT

				
Compares the values in register A and B and places a 1 if A < B, otherwise 0 in register R.

			

			

				
CMPGT

				
SCMPGT

				
FCMPGT

				
Compares the values in register A and B and places a 1 if A > B, otherwise 0 in register R.

			

			

				
CMPLTE

				
SCMPLTE

				
FCMPLTE

				
Compares the values in register A and B and places a 1 if A <= B, otherwise 0 in register R.

			
	
			

				
CMPGTE

				
SCMPGTE

				
FCMPGTE

				
Compares the values in register A and B and places a 1 if A >= B, otherwise 0 in register R.

			
		
			

				
CMPE

				
SCMPE

				
FCMPE

				
Compares the values in register A and B and places a 1 if A == B, otherwise 0 in register R.

			

			

				
CMPNE

				
SCMPNE

				
FCMPNE

				
Compares the values in register A and B and places a 1 if A != B, otherwise 0 in register R.

			

			

				
NEG

				
SNEG

				
FNEG

				

						Places a 1 in register R if the value in register A is zero.

						Places a 0 in register R if the value in register A is non-zero.


					

				

				

					
QADD VALUE VALUE

					
Sums the given immediate values A and B and saves the result in register R. (A + B)

				

				

					
QLADD ADDRESS VALUE

					
Sums the value located at the given address with the immediate value and saves the result in register R. (A + B)

				

				

					
QSUB VALUE VALUE

					
Substracts the given immediate values and saves the result in register R. (A - B)

				

				

					
QLSUB ADDRESS VALUE

					
Substracts the value located at the given address with the given immediate value and saves the result in register R. (A - B)