Release 231002

This release brings improvements to antenna diversity support on TFSIK01A.

Release 230728

This is a test release that introduces new GitHub actions build setup.

Snapshot of upstream with SDCC 3.0 srand code stripped, antenna diversity support on ISM01A added

Upstream emulates srand/rand code of SDCC 3.0 for compatibility, but there appear to be incompatible SiK firmware in circulation which base channel hopping on srand/rand behavior of later versions of SDCC. This release strips the SDCC 3.0 emulation code from upstream, includes ArduPilot#68, and is compiled with an SDCC 4.1.0 compiler. (Added support for antenna diversity on ISM01A/RFSWITCH.)

Snapshot of upstream with SDCC 3.0 srand code stripped

Upstream emulates srand/rand code of SDCC 3.0 for compatibility, but there appear to be incompatible SiK firmwares in circulation which base channel hopping on srand/rand behaviour of later versions of SDCC. This release strips the SDCC 3.0 emulation code from upstream, includes upstream PR #76 and is compiled with an SDCC 4.1.0 compiler.

Si1060 port with MAVLink 2 heartbeats and antenna diversity

Adds antenna diversity support.

Wiring of control signals between ISM01A and RFSWITCH01A:

ISM01A	RFSWITCH01A
GP0	CT of ANT1/ANT2
GP2	CT of RX/TX

Antenna diversity is enabled by default. The automatic choice of antenna can be temporarily overridden until the next reboot with command AT+A=. Use AT+A=1 to manually switch to antenna 1, AT+A=2 to switch to antenna 2.

Special release: One-way modification

This modified version of the firmware only supports one-way communication. It was flown on the FIK-6 stratospheric balloon flight.