SAF1761BE/V1,557 NXP Semiconductors, SAF1761BE/V1,557 Datasheet - Page 87

• Manufacturer Part Number: SAF1761BE/V1,557
• Manufacturer: NXP Semiconductors

Specifications of SAF1761BE/V1,557

• Lead Free Status / Rohs Status: Compliant

NXP Semiconductors
SAF1761_1
Product data sheet
9.4.2 OTG state diagrams
Figure 14
B-device, respectively. For a detailed explanation, refer to
to the USB Specification Rev.
The OTG state machine is implemented with software. The inputs to the state machine
come from four sources: hardware signals from the USB bus, software signals from the
application program, internal variables with the state machines, and timers:
6. The A-device detects lack of bus activity for more than 3 ms and turns off its DP
7. The B-device turns on its pull-up.
8. After waiting 30 s to ensure that the DP line is not HIGH because of the residual
•
•
•
•
pull-up. Alternatively, if the A-device has no further need to communicate with the
B-device, the A-device may turn off V
effect of the A-device pull-up, the A-device notices that the DP-line is HIGH and the
DM line is LOW, indicating that the B-device is signaling a connect and is ready to
respond as a peripheral. At this point, the A-device becomes a host and asserts the
bus reset to start using the bus.
Hardware inputs: Include id, a_vbus_vld, a_sess_vld, b_sess_vld, b_sess_end,
a_conn, b_conn, a_bus_suspend, b_bus_suspend, a_bus_resume, b_bus_resume,
a_srp_det and b_se0_srp. All these inputs can be derived from the OTG Interrupt and
OTG Status registers.
Software inputs: Include a_bus_req, a_bus_drop and b_bus_req.
Internal variables: Include a_set_b_hnp_en, b_hnp_enable and b_srp_done.
Timers: The HNP state machine uses four timers: a_wait_vrise_tmr,
a_wait_bcon_tmr, a_aidl_bdis_tmr and b_ase0_brst, tmr. All timers are started on
entry to and reset on exit from their associated states. The SAF1761 provides a
programmable timer that can be used as any of these four timers.
and
Figure 15
Rev. 01 — 18 November 2009
show state diagrams for the dual-role A-device and the dual-role
1.3”.
BUS
and end the session.
Ref. 3 “On-The-Go Supplement
Hi-Speed USB OTG controller
SAF1761
© NXP B.V. 2009. All rights reserved.
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