write_hex_file: new parameter byte_count, can choose hex data field length

Author: erki1993

intelhex/__init__.py

@@ -544,7 +544,7 @@ def _get_eol_textfile(eolstyle, platform):
             raise ValueError("wrong eolstyle %s" % repr(eolstyle))
     _get_eol_textfile = staticmethod(_get_eol_textfile)
 
-    def write_hex_file(self, f, write_start_addr=True, eolstyle='native'):
+    def write_hex_file(self, f, write_start_addr=True, eolstyle='native', byte_count=16):
         """Write data to file f in HEX format.
 
         @param  f                   filename or file-like object for writing
@@ -555,6 +555,7 @@ def write_hex_file(self, f, write_start_addr=True, eolstyle='native'):
         @param  eolstyle            can be used to force CRLF line-endings
                                     for output file on different platforms.
                                     Supported eol styles: 'native', 'CRLF'.
+        @param byte_count           number of bytes in the data field
         """
         fwrite = getattr(f, "write", None)
         if fwrite:
@@ -656,7 +657,7 @@ def write_hex_file(self, f, write_start_addr=True, eolstyle='native'):
                     # produce one record
                     low_addr = cur_addr & 0x0FFFF
                     # chain_len off by 1
-                    chain_len = min(15, 65535-low_addr, maxaddr-cur_addr)
+                    chain_len = min(byte_count - 1, 65535-low_addr, maxaddr-cur_addr)
 
                     # search continuous chain
                     stop_addr = cur_addr + chain_len