Add Intel HEX support with the help of the IHex library. IHex needed
some modifications to make it work with Python 3.
Intel HEX files are autodetected, based on file extension (.hex,
.ihx or .ihex).
Split up single script into a package with multiple modules.
Also add a setuptools control file. With this, stcgal can be
installed like any other program. It's still possible to launch
from the sources directly. stcgal.py has been converted into a
simple launcher.
v2: fix imports
The protocol originally named "stc15" is only used for two early STC15
series, i.e. STC15F104/STC15F204. All other STC15 series appear to
use a different protocol. So switch around names similary to "stc12"
vs "stc12a".
In conclusion:
- "stc15a" is used only for STC15xx04E(A)
- "stc15" is used for all other currently tested STC15 MCUs
These use a somewhat modified protocol with support for external clock.
This should get all STC/IAP15F2/L2 etc. work correctly. Only parts with
BSL 7.1 were tested, although BSL 7.2 should work as well.
The functionality is encapsulated in the new protocol "stc15x".
STC12A is my name for the mixup protocol between STC89 and
STC12 that is used by some early STC12 series MCUs (for examples
STC12C2052AD). The protocol differs in many subtle ways so there is
quite a bit of unfortunate code duplication for the moment.
The MCU might still be running user code and toggling the UART pins
when stcgal is started. Just ignore all garbage we see in this stage
until we get a valid package.
