Fix examples to build on RP2040
Clean up generator warnings
No SPDIF on RP2040 (yet)
Add back C sources for AAC on ARM
No WiFi streaming on RP2040
No webradio on RP2040
No talking clock (NTP) on RP2040 either
Because we are allocating objects totaling over 80% of the ESP8266 memory
space, we are very sensitive to memory fragmentation. While we can control
our own allocs, the IP and SDK can allocate any size, at any time, which
can cause us to not be able to find the large contiguous memory areas we need
for the codes.
Work around this by preallocating, before anything else, buffer memory and
never freeing it. Pass this memory into the codec and it will allocate from
this block and be guaranteed to always succeed.
This may fix the last of the hangs on the webradio/http streaming, which only
seemed to happen after a stop/start cycle.
Because the mp3 player is a long living object and needs to allocate
large contiguous chunks on each frame, it is safer to allocate the
large xr[] and tmp[] arrays at the beginning. Add them to the frame
structure which lives the entire time the mp3 object is alive. No
heap allocations are now used by the mp3 player.
Move the imdct_s[] array to progmem, but do a memcpy_P() to stack
as the macros may cause a 16-bit access after optimization. It's only
36 words long and each data is read, anyway, so this doesn't increase
the CPU work significantly.
Earle F. Philhower, III