class Main(object):
def __init__(self, f):
self.asm_file = f
self.table = SymbolTable()
self.data = self.read_file()
self.parser = Parser(self.data)
self.commands = self.parser.commands
self.translator = Translator()
self.filename = self.asm_file.split(".")[0]
def read_file(self):
with open(self.asm_file) as f:
data = f.readlines()
return data
def write_file(self, output_lines):
with open('%sassembled.hack' % self.filename, 'w') as output_file:
for line in output_lines:
output_file.write(line + '\n')
def assemble(self):
self.first_pass()
output_lines = self.second_pass()
self.write_file(output_lines)
def first_pass(self):
program_line = 0
for line in self.commands:
# if we have encountered a label pseudocommand
# check if it is in the table, if not assign it to value of next program line
# don't increment program counter because this shouldn't count as a program line
if line[0] == '(':
if not self.table.contains(line[1:-1]):
self.table.add_entry(line[1:-1], program_line)
continue
# if none of these conditions are hit, keep incrementing program line
program_line += 1
def second_pass(self):
translated_commands = []
next_available_RAM = 16
for line in self.commands:
if line[0] == '@':
symbol = line[1:]
try:
# translate directly if @ is referencing a specific value
translated_commands.append('{0:016b}'.format(int(symbol)))
continue
except ValueError:
pass
# check if symbol is already in the symbol table and convert value to binary
if self.table.contains(symbol):
translated_commands.append('{0:016b}'.format(
self.table.get_address(symbol)))
# add symbol to symbol table, increment available RAM count, and translate to binary
else:
self.table.add_entry(symbol, next_available_RAM)
next_available_RAM += 1
translated_commands.append('{0:016b}'.format(
self.table.get_address(symbol)))
elif line[0] == '(':
continue
else:
translated_commands.append(
self.translator.handle_C_instruction(line))
return translated_commands
