combine_flash_dump_emma.py

#!/usr/bin/env python3
# SPDX-License-Identifier: MIT

import sys

with open(sys.argv[1], "rb") as f:
	a = f.read()
with open(sys.argv[2], "rb") as f:
	b = f.read()

if len(a) != len(b):
	raise Exception("invalid size")

if (a[0] != 0xFF and b[0] == 0xFF) or (a[0] == 0x6F and b[0] == 0x74):
	tmp = b
	b = a
	a = tmp

needs_byteswap = a[0] == 0x74 and b[0] == 0x6F

c = bytearray(len(a) + len(b))

for i in range(0, len(c), 2):
	c[i] = a[i // 2]
	c[i + 1] = b[i // 2]

if needs_byteswap:
    for i in range(0, len(c), 4):
        tmp = c[i]
        c[i] = c[i + 3]
        c[i + 3] = tmp
        tmp = c[i + 1]
        c[i + 1] = c[i + 2]
        c[i + 2] = tmp

with open(sys.argv[3], "wb") as wf:
	wf.write(c)