From fb55a1bac036b470da14095ac16655aeb3d2fd17 Mon Sep 17 00:00:00 2001
From: Alexander Bessman <alexander.bessman@scania.com>
Date: Fri, 22 Sep 2023 12:28:46 +0200
Subject: [PATCH] Add support for Microchip HEX (close #38)

---
 bincopy.py            | 39 +++++++++++++++++++++++++++++++++++++++
 tests/test_bincopy.py |  7 +++++++
 2 files changed, 46 insertions(+)

diff --git a/bincopy.py b/bincopy.py
index 1aaa676..946f130 100755
--- a/bincopy.py
+++ b/bincopy.py
@@ -1101,6 +1101,36 @@ def add_elf(self, data, overwrite=True):
                                                self.word_size_bytes),
                                        overwrite)
 
+    def add_microchip_hex(self, records, overwrite=False):
+        """Add given Microchip HEX data.
+
+        Microchip's HEX format is identical to Intel's except an address in
+        the HEX file is twice the actual machine address. For example:
+
+        :02000E00E4C943
+
+            :       Start code
+            02      Record contains two data bytes
+            000E    Address 0x000E; Machine address is 0x000E // 2 == 0x0007
+            00      Record type is data
+            E4      Low byte at address 0x0007 is 0xE4
+            C9      High byte at address 0x0007 is 0xC9
+
+        Microchip HEX records therefore need to be parsed as if the word size
+        is one byte, but the parsed data must be handled as if the word size
+        is two bytes. This is true for both 8-bit PICs such as PIC18 and
+        16-bit PICs such as PIC24.
+
+        """
+
+        self.word_size_bytes = 1
+        self.add_ihex(records, overwrite)
+        self.word_size_bytes = 2
+        self.segments.word_size_bytes = 2
+
+        for segment in self.segments:
+            segment.word_size_bytes = 2
+
     def add_file(self, filename, overwrite=False):
         """Open given file and add its data by guessing its format. The format
         must be Motorola S-Records, Intel HEX, TI-TXT. Set `overwrite`
@@ -1171,6 +1201,15 @@ def add_elf_file(self, filename, overwrite=False):
         with open(filename, 'rb') as fin:
             self.add_elf(fin.read(), overwrite)
 
+    def add_microchip_hex_file(self, filename, overwrite=False):
+        """Open given Microchip HEX file and add its contents. Set `overwrite`
+        to ``True`` to allow already added data to be overwritten.
+
+        """
+
+        with open(filename, 'r') as fin:
+            self.add_microchip_hex(fin.read(), overwrite)
+
     def as_srec(self, number_of_data_bytes=32, address_length_bits=32):
         """Format the binary file as Motorola S-Records records and return
         them as a string.
diff --git a/tests/test_bincopy.py b/tests/test_bincopy.py
index f0cb72d..ba11a8b 100644
--- a/tests/test_bincopy.py
+++ b/tests/test_bincopy.py
@@ -1856,6 +1856,13 @@ def test_segment_len_16(self):
                                   word_size_bytes)
         self.assertEqual(length, len(segment))
 
+    def test_add_microchip_hex_record(self):
+        binfile = bincopy.BinFile()
+        binfile.add_microchip_hex(':02000E00E4C943')
+        self.assertEqual(0x0007, binfile.minimum_address)
+        first_word = int.from_bytes(binfile[:binfile.minimum_address + 1], "little")
+        self.assertEqual(0xC9E4, first_word)
+
 
 if __name__ == '__main__':
     unittest.main()