stm32/mboot/fwupdate.py: Simplify calculation of CRC32.

Signed-off-by: Damien George <damien@micropython.org>
3 years ago · 80055c2cdc
1 changed files with 3 additions and 5 deletions
--- a/ports/stm32/mboot/fwupdate.py
+++ b/ports/stm32/mboot/fwupdate.py
@ -75,12 +75,10 @@ def dfu_read(filename):
        return None

    hdr = f.read(16)
-    crc = crc32(hdr[:-4], crc)
-    hdr = struct.unpack("<HHHH3sBI", hdr)
-
+    crc = crc32(hdr, crc)
    crc = ~crc & 0xFFFFFFFF
-    if crc != hdr[-1]:
-        print("CRC failed", crc, hdr[-1])
+    if crc != 0:
+        print("CRC failed", crc)
        return None

    return elems