argentum11 / de0_mcu

A simple mcu for DE0

Environment

• chip : PIC16LF1826
• assembly editor : MPLAB v8.92 Debug assembly in MPLAB
• project program : Quartus || Web Edition 13.1
• simulation : ModelSim ALTERA STARTER EDITION 10.1d

Simulation steps

1. Select a example in example directory (the following steps shows how to simulate call_return)
2. Copy the design folder in DE0_mcu/example/call_return/de0 to DE0_mcu/
3. Copy 3 .do files(compile.do, sim.do, wave.do) in DE0_mcu/example/call_return/de0/simulation/modelsim/ to DE0_mcu/simulation/modelsim/
   • All systemverilog file paths should be added into compile.do
4. Copy testbench.sv in DE0_mcu/example/call_return/de0/simulation/tb/ to DE0_mcu/simulation/tb/
   • testbench.sv should match the file listed in sim.do
5. Open quartus project file (mcu.qpf)
6. Right click mcu, click settings and select all the files you need in design folder
7. Choose "RTL Simulation" in Flow
8. Execute task 1 - Analysis & Elaboration
9. Execute task 2 - RTL Simulation (This step opens ModelSim)
10. In the Transcript of ModelSim execute do compile.do
11. After successfully finish step 5, go on and execute do sim.do
12. You should see be able to see the wave that you selected in simulation/modelsim/wave.do

PIC16F1826 Instruction set

instruction	description	save to		signal
Literal Operations				number = kkkk kkkk
MOVLW	move a number to w			11 0000 kkkk kkkk
ADDLW	kkkk_kkkk + w	w		11 1110 kkkk kkkk
IORLW	kkkk_kkkk | w	w		11 1000 kkkk kkkk
ANDLW	kkkk_kkkk & w	w		11 1001 kkkk kkkk
SUBLW	kkkk_kkkk - w	w		11 1100 kkkk kkkk
XORLW	kkkk_kkkk ^ w (XOR)	w		11 1010 kkkk kkkk
				.
Register Operations		d=ir_out[7]
ADDWF	w + fff_ffff (register file address 0x00~0x7f)	d==0	w	00 0111 dfff ffff
		d==1	register
ANDWF	w & fff_ffff	d==0	w	00 0101 dfff ffff
		d==1	register
CLRF	clear fff_ffff to 0	register		00 0001 1fff ffff
CLRW	clear w to 0	w		00 0001 0000 00xx (x:Don't care)
COMF	not fff_ffff	d==0	w	00 1001 dfff ffff
		d==1	register
DECF	fff_ffff - 1	d==0	w	00 0011 dfff ffff
		d==1	register
INCF	fff_ffff + 1	d==0	w	00 1010 dfff ffff
		d==1	register
IORWF	w | fff_ffff	d==0	w	00 0100 dfff ffff
		d==1	register
MOVF	move fff_ffff to	d==0	w	00 1000 dfff ffff
		d==1	register
SUBWF	fff_ffff - w	d==0	w	00 0010 dfff ffff
		d==1	register
XORWF	fff_ffff ^ w	d==0	w	00 0110 dfff ffff
		d==1	register
		addr_port_b = (ir_out[6:0]==7'h0d)
MOVWF	move w to	addr_port_b == 0	register	00 0000 1fff ffff
		addr_port_b == 1	port_b
		sel_bit=ir_out[9:7]
BCF	bit clear f (set sel_bit to 0)	register		01 00bb bfff ffff
BSF	bit set f (set sel_bit to 1)	register		01 01bb bfff ffff
				.
Skip Operations
BTFSC	bit Test f, Skip if Clear (sel_bit==0)			01 10bb bfff ffff
BTFSS	bit Test f, Skip if Set (sel_bit==1)			01 11bb bfff ffff
DECFSZ	Decrement f, Skip if 0			00 1011 dfff ffff
INCFSZ	Increment f, Skip if 0			00 1111 dfff ffff
PORTBCSZ	skip 2 instructions if((port_b_out & port_c_out) == 0)			00 0000 0000 0011
INCFEQCSZ	Increment register(ir_out[7:0]), Skip if it equals port_c_out			11 0100 kkkk kkkk
				.
Rotate Operations
ASRF	remain sign bit and right shift fff_ffff	d==0	w	11 0111 dfff ffff
	=>{ mux1_out[7],mux1_out[7:1] }	d==1	register
LSLF	left shift fff_ffff	d==0	w	11 0101 dfff ffff
	=>{ mux1_out[6:0], 1'b0 }	d==1	register
LSRF	right shift fff_ffff	d==0	w	11 0110 dfff ffff
	=>{ 1'b0, mux1_out[7:1] }	d==1	register
RLF	rotate left fff_ffff	d==0	w	00 1101 dfff ffff
	=>{ mux1_out[6:0], mux1_out[7] }	d==1	register
RRF	rotate right fff_ffff	d==0	w	00 1100 dfff ffff
	=>{ mux1_out[0], mux1_out[7:1] }	d==1	register
SWAP	do half swap on fff_ffff	d==0	w	00 1110 dfff ffff
	{m7, m6,...m4, m3,...m0} => {m3,...m0, m7, m6,...m4}	d==1	register
				.
Control Operations
GOTO	PC_out = ir_out[10:0]			10 1fff ffff ffff
CALL	stack[stk_ptr + 1]=pc_q			10 0kkk kkkk kkkk
RETURN	pc_q = stack[stk_ptr]			00 0000 0000 1000
BRA	pc_next = pc_q + {ir_out[8], ir_out[8], ir_out[8:0]} - 1	limit: 255 instructions backward or 256 instructions forward		11 001k kkkk kkkk
BRW	pc_next = pc_q + {3'b0, w_q} - 1			00 0000 0000 1011
NOP	No Operation			00 0000 0000 0000

Hardware structure

de0_mcu's Issues

Assembly - how to debug

• week12, starts at 04:06
• week10, starts at 04:10
• add README.md about how to debug

READ.ME - graph

READ.ME - ModelSim

check the version of ModelSim and add it into READ.ME - environments

Code

Push the project code to this repo

Add gitignore for project