# from sys import exit import time import board import displayio # import vectorio import terminalio # for font from adafruit_display_text import label import keypad from digitalio import DigitalInOut, Direction, Pull # to list board features: print(board.__dir__) btna = DigitalInOut(board.BTNA) btna.direction = Direction.INPUT btna.pull = Pull.UP # down doesn't work btnb = DigitalInOut(board.BTNB) btnb.direction = Direction.INPUT btnb.pull = Pull.UP # down doesn't work km = keypad.KeyMatrix( row_pins = (board.P0, board.P1, board.P2, board.P3), column_pins = (board.P4, board.P6, board.P8, board.P9) ) class CPU: def __init__(self): self.running = False self.IP = 254 self.acc = 0 self.flags = { 'C': False, 'Z': False, 'N': False, 'Eq': False } self.instruction = { 'opcode': False, 'operand': False } self.memory = False self.monitorMode = 'addressEntry' # dataEntry self.monitorAddressInput = "00" self.monitorDataInput = "00" self.monitorAddressDisplay = "00" self.monitorDataDisplay = "00" def load_memory(self, bytes): self.memory = bytes + bytearray(256 - len(bytes)) print(type(self.memory)) print('mem 254', self.memory[254]) # print(self.memory) def start(self): self.running = True def print_screen(self): for i in range(5): for j in range(5): # print(f"{i}-{j}", end=" ") # print(self.memory[(i*5)+j], end=" ") memory_index = (i * 5) + j if self.memory[memory_index] > 0: print("#", end=" ") else: print("_", end=" ") print() def print_monitor(self): displayGroup = displayio.Group() board.DISPLAY.root_group = displayGroup text = self.monitorAddressDisplay + " " + self.monitorDataDisplay text_area = label.Label(terminalio.FONT, text=text) text_area.x = 10 text_area.y = 100 displayGroup.append(text_area) def read_keys(self): keypad_event = km.events.get() if keypad_event and keypad_event.released: print(keypad_event.key_number) if self.running: if btna.value == False: self.running = False print("HALT PRESSED") time.sleep(0.5) # lazy debounce # km.events.clear() # don't track keypresses from during the run if keypad_event and keypad_event.released: self.memory[26] = keypad_event.key_number print("mem26", self.memory[26]) else: # halted if btna.value == False: self.running = True print("STARTING") time.sleep(0.5) # lazy debounce if btnb.value == False: self.monitorMode = 'addressEntry' if self.monitorMode != 'addressEntry' else 'dataEntry' print(self.monitorMode) time.sleep(0.5) # lazy debounce if keypad_event and keypad_event.released: new_digit_0x = hex(keypad_event.key_number) new_digit = new_digit_0x[2:3] if self.monitorMode == 'addressEntry': cat = self.monitorAddressInput + new_digit self.monitorAddressInput = cat[1:3] print("MA", self.monitorAddressInput) else: cat = self.monitorDataInput + new_digit self.monitorDataInput = cat[1:3] print("MD", self.monitorDataInput) print("Acc", self.acc, "Addr", self.monitorAddressInput, "Data", self.memory[int(self.monitorAddressInput)]) # TODO: update data with keypad # then, automatically go to next address (?) def step(self): if self.IP >= 256: self.IP = 0 print("IP:", self.IP) self.instruction['opcode'] = self.memory[self.IP] self.IP = self.IP+1 self.instruction['operand'] = self.memory[self.IP] self.IP = self.IP+1 print("instr:", self.instruction['opcode'], self.instruction['operand']) print("mnem:", self.nums2mnems[self.instruction['opcode']]) self.nums2mnems[self.instruction['opcode']](self, self.instruction['operand']) print("acc:", self.acc) print("running:", self.running) print() # self.print_screen() print("byte 26 (keyboard):", self.memory[26]) print() # if not self.running: # exit() def run(self): self.start() t = time.time() while (time.time() - t) < 30: self.read_keys() #self.print_monitor() #if self.running: # self.step() # time.time.sleep(0.5) print("timeout") def hlt(self, operand): self.running = False def nop(self, operand): pass def lda_lit(self, operand): self.acc = operand def lda_mem(self, operand): self.acc = memory[operand] def sta_lit(self, operand): memory[operand] = self.acc def sta_mem(self, operand): memory[memory[operand]] = self.acc def add_lit(self, operand): self.acc = self.acc + operand if self.acc > 255: self.acc = self.acc % 256 self.flags['C'] = True else: self.flags['C'] = False self.flags['Z'] = True if self.acc == 0 else False self.flags['Eq'] = True if self.acc == operand else False self.flags['N'] = True if self.acc > 127 else False def add_mem(self, operand): self.acc = self.acc + self.memory[operand] if self.acc > 255: self.acc = self.acc % 256 self.flags['C'] = True else: self.flags['C'] = False self.flags['Z'] = True if self.acc == 0 else False self.flags['Eq'] = True if self.acc == operand else False self.flags['N'] = True if self.acc > 127 else False def sub_lit(self, operand): self.acc = self.acc - operand if self.acc < 0: self.acc = self.acc % 256 self.flags['C'] = True else: self.flags['C'] = False self.flags['Z'] = True if self.acc == 0 else False self.flags['Eq'] = True if self.acc == operand else False self.flags['N'] = True if self.acc > 127 else False def sub_mem(self, operand): self.acc = self.acc - self.memory[operand] if self.acc > 255: self.acc = self.acc % 256 self.flags['C'] = True else: self.flags['C'] = False self.flags['Z'] = True if self.acc == 0 else False self.flags['Eq'] = True if self.acc == operand else False self.flags['N'] = True if self.acc > 127 else False def jmp_lit(self, operand): self.IP = operand def jmp_mem(self, operand): self.IP = memory[operand] def ske(self, operand): if self.flags['Eq']: self.IP += 2 def skz(self, operand): if self.flags['Z']: self.IP += 2 def skn(self, operand): if self.flags['N']: self.IP += 2 def skc(self, operand): if self.flags['C']: self.IP += 2 def cst(self, operand): self.flags['C'] = True def ccl(self, operand): self.flags['C'] = False nums2mnems = { 0: hlt, 1: nop, 2: lda_lit, 3: sta_lit, 4: add_lit, 5: sub_lit, 6: jmp_lit, 7: ske, 8: skz, 9: skn, 10: skc, 11: cst, 12: ccl, 16: hlt, 17: nop, 18: lda_mem, 19: sta_mem, 20: add_mem, 21: sub_mem, 22: jmp_mem, 23: ske, 24: skz, 25: skn, 26: skc, 27: cst, 28: ccl, } cpu = CPU() prog = '04 FF 04 01 14 01 00 00' program_bytes = bytearray.fromhex(prog.replace(" ", "")) # Add jmp at addr 254: program_with_jump = program_bytes + bytearray(254 - len(program_bytes)) + bytearray.fromhex('0600') cpu.load_memory(program_with_jump) # cpu.start() # cpu.step() cpu.run()