Broadcast packet based stylus pairing

1. A stylus, comprising:

a processor; and

memory holding instructions executable by the processor to:

before sending a pairing request to a display, receive a broadcast packet indicating, for each of a set of stylus communication slots of the display, an occupancy of the stylus communication slot;

determine that at least one stylus communication slot is available based on the broadcast packet; and

responsive to determining that the at least one stylus communication slot is available, selectively send the pairing request to occupy a stylus communication slot based on a pairing request history.

2. The stylus of claim 1 , where the pairing request history includes a number of pairing requests sent by the stylus, and where selectively sending the pairing request to occupy the stylus communication slot based on the pairing request history includes sending the pairing request after an interval, the interval increasing as a function of the number of pairing requests sent by the stylus.

3. The stylus of claim 1 , where the instructions are further executable to, after sending the pairing request to occupy the stylus communication slot, receive an acknowledgment packet indicating pairing of the stylus to the display.

4. The stylus of claim 3 , where the instructions are further executable to, after receiving the acknowledgment packet, communicate with the display via an electrostatic link.

5. The stylus of claim 1 , where the pairing request is sent via a radio link.

6. The stylus of claim 1 , where the set of stylus communication slots is a set of temporal stylus communication slots.

7. The stylus of claim 1 , where the instructions are further executable to:

determine that no stylus communication slot is available; and

responsive to determining that no stylus communication slot is available, wait for a future broadcast packet indicating stylus communication slot availability before sending the pairing request.

8. The stylus of claim 1 , where the instructions are further executable to, after sending the pairing request, update the pairing request history.

9. The stylus of claim 1 , where determining that at least one stylus communication slot is available includes determining that at least two stylus communication slots are available, and where the instructions are further executable to randomly select one of the at least two available stylus communication slots for sending the pairing request.

10. The stylus of claim 1 , where the broadcast packet includes an identifier of each stylus occupying a respective stylus communication slot, and where the instructions are further executable to not send the pairing request responsive to identifying a match between an identifier of the stylus and an identifier of one of the styluses occupying a respective stylus communication slot.

11. On a stylus, a method, comprising:

before sending a pairing request to a display, receiving a broadcast packet indicating, for each of a set of stylus communication slots of the display, an occupancy of the stylus communication slot;

determining that at least one stylus communication slot is available based on the broadcast packet; and

responsive to determining that the at least one stylus communication slot is available, selectively sending the pairing request to occupy a stylus communication slot based on a pairing request history.

12. The method of claim 11 , where the pairing request history includes a number of pairing requests sent by the stylus, and where selectively sending the pairing request to occupy the stylus communication slot based on the pairing request history includes sending the pairing request after an interval, the interval increasing as a function of the number of pairing requests sent by the stylus.

13. The method of claim 11 , further comprising:

determining that no stylus communication slot is available; and

responsive to determining that no stylus communication slot is available, waiting for a future broadcast packet indicating stylus communication slot availability before sending the pairing request.

14. The method of claim 11 , further comprising, after sending the pairing request, updating the pairing request history.

15. The method of claim 11 , where determining that at least one stylus communication slot is available includes determining that at least two stylus communication slots are available, the method further comprising randomly selecting one of the at least two available stylus communication slots for sending the pairing request.

16. A display, comprising:

a processor; and

memory holding instructions executable by the processor to:

determine an occupancy of a set of stylus communication slots;

transmit a broadcast packet indicating, for each of the set of stylus communication slots, an occupancy of the stylus communication slot, the broadcast packet configured to trigger transmission of a pairing request from a stylus if the broadcast packet indicates stylus communication slot availability;

receive a pairing request from the stylus to occupy one of the set of stylus communication slots; and

responsive to determining that at least one stylus communication slot is available, pair the stylus to the display.

17. The display of claim 16 , where the instructions are further executable to:

identify a least recently used stylus communication slot from among the two or more stylus communication slots that exceed the threshold inactivity; and

pair the stylus to the display through the least recently used stylus communication slot.

18. The display of claim 16 , where the instructions are further executable to:

determine that a stylus communication slot exceeds a threshold inactivity;

unpair an occupant of the stylus communication slot that exceeds the threshold inactivity; and

designate the stylus communication slot that exceeds the threshold inactivity as being available.

19. The display of claim 18 , where the instructions are further executable to, after designating the stylus communication slot as being available, transmit an updated broadcast packet indicating availability of the stylus communication slot.

20. The display of claim 16 , further comprising a radio transceiver, where the broadcast packet is transmitted via the radio transceiver.