def read_fuses(self, dev):
"""Reads the fuse and lock bits from the target and returns them as a named tuple."""
# set up constants
buf = [
asm.ldi(29, RFLB | SPMEN), # ldi r29, RFLB | SPMEN
asm.ldi(31, 0), # ldi r31, 0 ; (high byte of Z)
]
# there are four bytes to read
for index in reversed(range(4)):
# read fuse/lock bit into r0
buf += [
asm.ldi(30, index), # ldi r31, index ; (low byte of Z)
asm.out(dev.reg_spmcsr, 29), # out SPMCSR, r29 ; RFLB | SPMEN
asm.lpm(), # lpm
]
# move into another register if not reading index 0
if index != 0:
buf += [
asm.mov(index, 0), # mov r[index], r0
]
# execute generated code
self._exec(buf)
# read r0-r3 which now contain the bytes that were read
return Fuses(*self.read_regs(0, 4))
def read_fuses(self, dev):
"""Reads the fuse and lock bits from the target and returns them as a named tuple."""
# set up constants
buf = [
asm.ldi(29, RFLB | SPMEN), # ldi r29, RFLB | SPMEN
asm.ldi(31, 0), # ldi r31, 0 ; (high byte of Z)
]
# there are four bytes to read
for index in reversed(range(4)):
# read fuse/lock bit into r0
buf += [
asm.ldi(30, index), # ldi r31, index ; (low byte of Z)
asm.out(dev.reg_spmcsr, 29), # out SPMCSR, r29 ; RFLB | SPMEN
asm.lpm(), # lpm
]
# move into another register if not reading index 0
if index != 0:
buf += [
asm.mov(index, 0), # mov r[index], r0
]
# execute generated code
self._exec(buf)
# read r0-r3 which now contain the bytes that were read
return Fuses(*self.read_regs(0, 4))
def write_flash_page(self, dev, start, data):
if start % dev.flash_pagesize != 0:
raise DWException("Bad page offset")
if len(data) != dev.flash_pagesize:
raise DWException("Bad page size")
prof = (SimpleProfiler if self.enable_log else DummyProfiler)()
prof.step("Starting page write")
# set up constants in registers
self.write_regs(
26,
[
SPMEN, # r26
PGERS | SPMEN, # r27
PGWRT | SPMEN, # r28
CTPB | SPMEN, # r29
start & 0xff,
(start >> 8) & 0xff # r30:r31(Z)
])
# clear self-programming buffer
prof.step("Write constants")
self._exec([
asm.movw(24, 30), # movw r24, r30
asm.out(dev.reg_spmcsr, 29), # out SPMCSR, r29 ; CTPB | SPMEN
asm.spm()
]) # spm
self.iface.send_break()
prof.step("Clear buffer")
# erase flash page
self._exec([
asm.out(dev.reg_spmcsr, 27), # out SPMCSR, r27 ; PGERS | SPMEN
asm.spm(), # spm
])
# wait for erase to complete
self.iface.send_break()
prof.step("Erase page")
# write data to buffer
# How many instruction bytes to write at once
# The maximum suitable value for this is probably related to USB buffer sizes etc.
CHUNK_LEN = 16
for ci in range(0, len(data), CHUNK_LEN):
buf = []
for ii in range(ci, ci + CHUNK_LEN, 2):
if dev.reg_dwdr:
buf += [
asm.in_(dev.reg_dwdr, 0),
bytes([data[ii]]), # in r0, DWDR ; (low byte)
asm.in_(dev.reg_dwdr, 1),
bytes([data[ii + 1]])
] # in r1, DWDR ; (high byte)
else:
buf += [
asm.ldi(22, data[ii]), # ldi r22, (low byte)
asm.ldi(23, data[ii + 1]), # ldi r23, (high byte)
asm.movw(0, 22)
] # movw r0, r22
buf += [
asm.out(dev.reg_spmcsr, 26), # out SPMCSR, r26 ; SPMEN
asm.spm(), # spm
asm.adiw(30, 2)
] # adiw Z, 2
self._exec(buf)
prof.step("Write data")
# write buffer to flash
self._exec([
asm.movw(30, 24), # movw r30, r24
asm.out(dev.reg_spmcsr, 28), # out SPMCSR, r28 ; PGWRT | SPMEN
asm.spm()
]) # spm
# wait for write to complete
self.iface.send_break()
prof.step("Write flash")
def write_flash_page(self, dev, start, data):
if start % dev.flash_pagesize != 0:
raise DWException("Bad page offset")
if len(data) != dev.flash_pagesize:
raise DWException("Bad page size")
prof = (SimpleProfiler if self.enable_log else DummyProfiler)()
prof.step("Starting page write")
# set up constants in registers
self.write_regs(26, [
SPMEN, # r26
PGERS | SPMEN, # r27
PGWRT | SPMEN, # r28
CTPB | SPMEN, # r29
start & 0xff, (start >> 8) & 0xff # r30:r31(Z)
])
# clear self-programming buffer
prof.step("Write constants")
self._exec([
asm.movw(24, 30), # movw r24, r30
asm.out(dev.reg_spmcsr, 29), # out SPMCSR, r29 ; CTPB | SPMEN
asm.spm()]) # spm
self.iface.send_break()
prof.step("Clear buffer")
# erase flash page
self._exec([
asm.out(dev.reg_spmcsr, 27), # out SPMCSR, r27 ; PGERS | SPMEN
asm.spm(), # spm
])
# wait for erase to complete
self.iface.send_break()
prof.step("Erase page")
# write data to buffer
# How many instruction bytes to write at once
# The maximum suitable value for this is probably related to USB buffer sizes etc.
CHUNK_LEN = 16
for ci in range(0, len(data), CHUNK_LEN):
buf = []
for ii in range(ci, ci + CHUNK_LEN, 2):
if dev.reg_dwdr:
buf += [
asm.in_(dev.reg_dwdr, 0), bytes([data[ii]]), # in r0, DWDR ; (low byte)
asm.in_(dev.reg_dwdr, 1), bytes([data[ii + 1]])] # in r1, DWDR ; (high byte)
else:
buf += [
asm.ldi(22, data[ii]), # ldi r22, (low byte)
asm.ldi(23, data[ii + 1]), # ldi r23, (high byte)
asm.movw(0, 22)] # movw r0, r22
buf += [
asm.out(dev.reg_spmcsr, 26), # out SPMCSR, r26 ; SPMEN
asm.spm(), # spm
asm.adiw(30, 2)] # adiw Z, 2
self._exec(buf)
prof.step("Write data")
# write buffer to flash
self._exec([
asm.movw(30, 24), # movw r30, r24
asm.out(dev.reg_spmcsr, 28), # out SPMCSR, r28 ; PGWRT | SPMEN
asm.spm()]) # spm
# wait for write to complete
self.iface.send_break()
prof.step("Write flash")