This compiles, links, and starts the RTOS without crashing and burning.
Lua environment does not yet start due to the different task architecture.
Known pain points:
- task implementation needs to be rewritten for RTOS (next up on my TODO)
- secure espconn does not exist, all secure espconn stuff has been #if 0'd
- lwip now built from within the RTOS SDK, but does not appear to include
MDNS support. Investigation needed.
- there is no access to FRC1 NMI, not sure if we ever actually used that
however. Also #if 0'd out for now.
- new timing constraints introduced by the RTOS, all use of ets_delay_us()
and os_delay_us() needs to be reviewed (the tsl2561 driver in particular).
- even more confusion with ets_ vs os_ vs c_ vs non-prefixed versions.
In the long run everything should be switched to non-prefixed versions.
- system_set_os_print() not available, needs to be reimplemented
- all the RTOS rodata is loaded into RAM, as it apparently uses some
constants while the flash isn't mapped, so our exception handler can't
work its magic. This should be narrowed down to the minimum possible
at some point.
- with each task having its own stack in RTOS, we probably need change
flash-page buffers from the stack to the heap in a bunch of places.
A single, shared, page buffer *might* be possible if we limit ourselves
to running NodeMCU in a single task.
- there's a ton of junk in the sdk-overrides now; over time the core code
should be updated to not need those shims
The rtcfifo module uses RTC memory to store sensor samples across deep-sleeps,
making it possible to batch up samples for less frequent uploads. This
component uses 9 RTC memory slots for control, and a variable number of
slots for sample storage (see rtcfifo.prepare() on how to control the
size/location of the latter).
When used together with the rtctime module, it also exposes the convenience
function rtcfifo.dsleep_until_sample() which can be used to easily take
readings on a regular basis without having to manually take into account
time spent awake to get an accurate sleep time.
The format used for storing samples is quite dense, and allows for 16 bits
of data in a fixed point format (per sample).
Added Lua module rtctime to interface with it.
This keeps as accurate time as is possible on the ESP8266, including across
deep sleeps (provided rtctime.dsleep() is used rather than node.dsleep()).
Intended to be used together with NTP for high accuracy time keeping. The
API is via rtctime.{get,set}timeofday(), working from Unix epoch.
Note that 160MHz CPU clock is not currently supported by the rtctime code,
as it is only aware of the 52MHz boot clock and the regular 80Mhz default
clock.
See rtctime.h for detailed info on how this all works.
Johny Mattsson