First, i made a mistake above - the key at row 11, column 5 is the CBM key - but on a C16 keyboard (see the rightmost columns in that table). So you really want to change the key at row 7, column 5.
That said, don't get misleaded by those ASCII chars - the USB HID codes are not ASCII at all To find the right byte to modify, it helps a lot if your hex editor allows you to show arbitrary number of bytes per line.... when i set mine to 8 (the maximum number of columns) then you can clearly see (and edit) the matrix, it looks like this (beginning of cbm_us.bin):
- 0000:0000 | 2A 28 4F 51 3A 3C 3E 40 | *(OQ:<>@
- 0000:0008 | 20 1A 04 E1 1D 16 08 21 | ..á...!
- 0000:0010 | 22 15 07 1B 06 09 17 23 | "......#
- 0000:0018 | 24 1C 0A 19 05 0B 18 25 | $......%
- 0000:0020 | 26 0C 0D 11 10 0E 12 27 | &......'
- 0000:0028 | 2E 13 0F 36 37 2F 31 2D | ...67/1-
- 0000:0030 | 35 33 30 38 E5 34 4E 4A | 5308å4NJ
- 0000:0038 | 1E 29 E0 2B 2C E2 14 1F | .)à+,â..
- 0000:0040 | 2A 28 35 33 3A 3B 3C 41 | *(53:;<A
- 0000:0048 | 51 13 0F 36 37 2F 2D 52 | Q..67/-R
- 0000:0050 | 50 34 30 38 29 31 2E 4F | P408)1.O
- 0000:0058 | 1E 2B E0 00 2C E2 14 1F | .+à.,â..
- 0000:0060 | E6 62 63 47 51 50 4F 52 | æbcGQPOR
- 0000:0068 | 29 57 56 5B 58 5E 61 4D | )WV[X^aM
- 0000:0070 | 53 60 5D 59 5A 5C 5F 2B | S`]YZ\_+
- 0000:0078 | 00 00 00 00 00 00 00 00 | ........
- 0000:0080 | 00 00 00 00 00 00 00 00 | ........
So, the value you want to change is supposed to be at row 7, column 5 - meaning the offset in the file is (7*8) + 5 = 61 (hex 0x3d). If you look at the file now, at this offset you will find the hex value 0xe2 - which is "left alt", exactly whats expected And indeed, it should be changed to 0xe3 (the pdf you found is the same that i am looking at, so all good).