Format of Intel hex files

Intel hex files consist of a number of lines, each of the form

	:nnaaaattddddd...dcc

with

	:	start of record
	nn	length of record
	aaaa	memory address to load
	tt	type: 00 data, 01 end-of-file
	dd..d	data
	cc	checksum

All numbers are in ASCII hex. The checksum makes sure that the sum of all bytes is zero.

For example,

	:03000000021A20C1

says 3 bytes, address 0000, bytes 02, 1A, 20.

For example,

	:011A5000D2C3

says 1 byte, address 1A50 (hex), byte D2. We have 01 + 1A + 50 + 00 + D2 + C3 = 00.

For example,

	:00000001FF

is the end-of-file record.

Firmware download for Carry USB chips

Comparing the Intel hex file with what UsbSnoop sees:

	:100E5800C203C200C202C201120A9ED2E843D820CD

	10 00 58 0e 00 c2 03 c2 00 c2 02 c2 01 12 0a 9e
	d2 e8 43 d8 20 cd

we see that the number and the address are both sent as little endian shorts.

	:040EA8008080D6224E
	:10054600907FE9E070030206E114700302075D2460

	04 00 a8 0e 00 80 80 d6 22 4e 10 05 46 00 90 7f
	e9 e0 70 03 02 06

	10 00 46 05 00 90 7f e9 e0 70 03 02 06 e1 14 70
	03 02 07 5d 24 60

short records are padded with (random?) stuff, namely the start of the following record.