def CodeWord(data, list="True"):
"""
Write the code word to the target file.
We can't rely on target.CodeWord because that would change everything into
RETLW instructions.
"""
if dec.Asm.Memory != 0 and not dec.Flags.CodeWarn and dec.Asm.Pass == 2:
dec.Flags.CodeWarn = True
errors.DoWarning('notcode', True)
target.SaveByte(data & 0xFF, list)
target.SaveByte((data >> 8) & 0xFF, list)
def SaveByte(data, list=True):
"""
Save byte in code memory. We come here because a directive has generated
data to be written in code memory. If we're still below the program size
data bytes need to be translated to RETLW instructions. Otherwise a byte
has to be stored as a word with high byte 0.
Also check whether the end of memory is passed, in which case a warning
is issued.
"""
global Asm, Cross
if dec.Asm.Memory == 0:
# We only need to do something special inside code memory
if dec.Asm.PH_Address > dec.Asm.Max_Address:
# We're past the end of program memory. Save as word instead
# Temporarily raise program limit to avoid warnings
limit = dec.Asm.Max_Address
dec.Asm.Max_Address = 0x1FFF
# Save a word as usual
CodeWord(data & 0xFF, list)
# Restore original limit
dec.Asm.Max_Address = limit
else:
# Combine data with RETLW opcode
CodeWord(0x3400 + (data & 0xFF), list)
# This is an instruction, so it has an execution time
dec.Asm.Timing = "2"
else:
# All other memories can be done as usual
target.SaveByte(data, list)
def DirCW():
"""
Set the Configuration word.
This Configuration word is usually stored at the last location in memory,
which is word address $0FFF (or byte addresses ($1FFE and $1FFF).
Programming devices expect that word to be there. The SB-Assembler only
checks that the Configuration word is stored beyond the program memory.
"""
global Asm, Cross
if dec.Asm.Memory != 0:
# The .CW directive can only be used in program memory
errors.DoError(dec.Cross.Name + 'codemem', False)
return
if dec.Asm.PH_Address <= dec.Asm.Max_Address:
# We're still in program memory. We can't have that
errors.DoError(dec.Cross.Name + 'progmem', False)
return
if assem.NowChar() == '#':
# Ignore the # symbol
assem.NowChar(True)
config = assem.EvalExpr()[0]
if dec.Asm.Pass == 2 and (config < 0 or config > 0x0FFF):
# Only 12 bits allowed
errors.DoError('range', False)
# Temporarily raise program limit
limit = dec.Asm.Max_Address
dec.Asm.Max_Address = 0x0FFF
# Bypass the RETLW pointer
target.SaveByte(config & 0xFF)
target.SaveByte((config >> 8) & 0x0F)
# Restore original limit
dec.Asm.Max_Address = limit
NoMore()
def CodeWord(data, list="True"):
"""
Write the code word to the target file.
We don't have to anythong special for the PIC16. We only need to do a
boundary sync first.
"""
if dec.Asm.Memory != 0 and not dec.Flags.CodeWarn and dec.Asm.Pass == 2:
# It's useless to store program code in EEPROM or RAM memory
dec.Flags.CodeWarn = True
errors.DoWarning('notcode', True)
if dec.Asm.Memory == 0:
# OK, we're in code memory
if (dec.Asm.PH_Address % 2) != 0:
# We're at an odd address. Let's save a padding byte
target.SaveByte(0, False)
dec.Asm.BOL_Address = dec.Asm.PH_Address
dec.Asm.List_Address = dec.Asm.PH_Address
target.SaveByte(data & 0xFF, list)
target.SaveByte((data >> 8) & 0xFF, list)
def DirID():
"""
Set the ID words.
These ID words are usually stored directly behind the program memory, or
directly behind the EEPROM memory if that is present.
The SB-Assembler only checks that the Configuration word is stored beyond
the program memory.
"""
global Asm, Cross
if dec.Asm.Memory != 0:
# The .ID directive can only be used in program memory
errors.DoError(dec.Cross.Name + 'codemem', False)
return
if dec.Asm.PH_Address <= dec.Asm.Max_Address:
# We're still in program memory. We can't have that
errors.DoError(dec.Cross.Name + 'progmem', False)
return
if assem.NowChar() == '#':
# Ignore the # symbol
assem.NowChar(True)
id = assem.EvalExpr()[0]
# Temporarily raise program limit
limit = dec.Asm.Max_Address
dec.Asm.Max_Address = 0x0FFF
# Save the ID, one nibble at a time
target.SaveByte(id & 0x000F)
target.SaveByte(0)
target.SaveByte((id >> 4) & 0x000F)
target.SaveByte(0)
target.SaveByte((id >> 8) & 0x000F)
target.SaveByte(0)
target.SaveByte((id >> 12) & 0x000F)
target.SaveByte(0)
# Restore original limit
dec.Asm.Max_Address = limit
NoMore()
def BincHEX(line):
"""
Parse a plain HEX line.
This one's easy.
"""
for i in range(0, len(line), 2):
# Translate each hex digit pair into a byte
value = HexPair(line[i:i+2])
if not value[0]:
target.SaveByte(value[1], False)
else:
return True
return False
def DirID():
"""
Set the ID words.
These ID words are usually at word location $000 to $8003.
The SB-Assembler only checks that the Configuration word is stored beyond
the program memory.
ID words can only store the 7 least significant bits. The SB-Assembler
does not check the range. It simply truncates to 7 bits.
"""
global Asm, Cross
id2 = 0
id3 = 0
id4 = 0
if dec.Asm.Memory != 0:
# The .ID directive can only be used in program memory
errors.DoError(dec.Cross.Name + 'codemem', False)
return
if dec.Asm.PH_Address <= dec.Asm.Max_Address:
# We're still in program memory. We can't have that
errors.DoError(dec.Cross.Name + 'progmem', False)
return
if assem.NowChar() == '#':
# Ignore the # symbol
assem.NowChar(True)
id1 = assem.EvalExpr()[0]
if assem.MoreParameters():
# More than 1 ID word are given
if assem.NowChar() == '#':
# Ignore the # symbol
assem.NowChar(True)
id2 = assem.EvalExpr()[0]
if assem.MoreParameters():
# More than 2 ID word are given
if assem.NowChar() == '#':
# Ignore the # symbol
assem.NowChar(True)
id3 = assem.EvalExpr()[0]
if assem.MoreParameters():
# More than 1 ID word are given
if assem.NowChar() == '#':
# Ignore the # symbol
assem.NowChar(True)
id4 = assem.EvalExpr()[0]
# Temporarily raise program limit
limit = dec.Asm.Max_Address
dec.Asm.Max_Address = 0x1FFFF
# Save the ID, one nibble at a time
target.SaveByte(id1 & 0x007F)
target.SaveByte(0)
target.SaveByte(id2 & 0x007F)
target.SaveByte(0)
target.SaveByte(id3 & 0x007F)
target.SaveByte(0)
target.SaveByte(id4 & 0x007F)
target.SaveByte(0)
# Restore original limit
dec.Asm.Max_Address = limit
NoMore()