ISP1506A_08 Datasheet, PDF (29/80 Pages) NXP Semiconductors – ULPI Hi-Speed USB OTG transceiver

NXP Semiconductors
ISP1506A; ISP1506B
ULPI HS USB OTG transceiver
OTG devices: When an OTG device is configured as an OTG A-device, it must be able to
provide a minimum of 8 mA on V_BUS. If the OTG A-device provides less than 100 mA, then
there is no need for an overcurrent detection circuit because the internal A_VBUS_VLD
comparator is sufficient. If the OTG A-device provides more than 100 mA on V_BUS, an
overcurrent detector must be used and Section “Standard USB host controllers” applies.
The OTG A-device also uses SESS_VLD to detect when an OTG B-device is initiating
V_BUS pulsing SRP.
When an OTG device is configured as an OTG B-device, SESS_VLD must be used to
detect when V_BUS is at a sufficient level for operation. SESS_END must be used to detect
when V_BUS has dropped to a LOW level, allowing the B-device to safely initiate V_BUS
pulsing SRP.
9.5.2.4 RxEvent encoding
The RxEvent field (see Table 15) of the RXCMD informs the link of information related
packets received on the USB bus. RxActive and RxError are defined in Ref. 5 “USB 2.0
Transceiver Macrocell Interface (UTMI) Specification Ver. 1.05”. HostDisconnect is
defined in Ref. 4 “UTMI+ Specification Rev. 1.0”. A short definition is also given in the
following subsections.
Table 15.
Value
00
01
11
10
Encoded USB event signals
RxActive
0
1
1
X
RxError
0
0
1
X
HostDisconnect
0
0
0
1
RxActive: When the ISP1506 has detected a SYNC pattern on the USB bus, it signals an
RxActive event to the link. An RxActive event can be communicated using two methods.
The first method is for the ISP1506 to simultaneously assert DIR and NXT. The second
method is for the ISP1506 to send an RXCMD to the link with the RxActive field in
RxEvent bits set to logic 1. The link must be able to detect both methods. RxActive frames
the receive packet from the first byte to the last byte.
The link must assume that RxActive is set to logic 0 when indicated in an RXCMD or when
DIR is deasserted, whichever occurs first.
The link uses RxActive to time high-speed packets and ensure that bus turnaround times
are met. For more information on the USB packet timing, see Section 9.8.1.
RxError: When the ISP1506 has detected an error while receiving a USB packet, it
deasserts NXT and sends an RXCMD with the RxError field set to logic 1. The received
packet is no longer valid and must be dropped by the link.
HostDisconnect: HostDisconnect is encoded into the RxEvent field of the RXCMD.
HostDisconnect is valid only when the ISP1506 is configured as a host (both
DP_PULLDOWN and DM_PULLDOWN are set to logic 1), and indicates to the host
controller when a peripheral is connected or disconnected. The host controller must
enable HostDisconnect by setting the HOST_DISCON_R and HOST_DISCON_F bits in
the USB Interrupt Enable Rising Edge and USB Interrupt Enable Falling Edge registers,
respectively. Changes in HostDisconnect will cause the PHY to send an RXCMD to the
link with the updated value.
ISP1506A_ISP1506B_2
Product data sheet
Rev. 02 — 28 August 2008
© NXP B.V. 2008. All rights reserved.
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