Allocate a new 'struct pollreactor' object

Internal code to invoke timer callbacks

Free resources associated with a 'struct pollreactor' object

Return the last schedule wake-up time for a timer

Repeatedly check for timer and fd events and invoke their callbacks

Main processing loop

Process incoming data from PIO "rx" state machine

Slow path for queue_append() - expand the internal queue storage

Slow path for queue_append() - handle next step far in future

Report error to calling code (via callback interface)

Report a received message to calling code (via callback interface)

Report a message that was successfully transmited (via callback interface)

Check if message being processed is an rx message (not self feedback from tx)

Received PIO rx "ackdone" irq

Received PIO "matched" irq

Received 10+ passive bits on the line (between 10 and 17 bits)

Schedule a transmit

Parser found successful ack

Setup for ack injection (if receiving) or ack confirmation (if transmit)

Parser successfully found matching crc

Parser found unexpected data on input

Parser found a new message start

Calculate upper arm angle given xy position of effector joint (relative to shoulder joint), upper arm length, and lower arm length.