SAF1761BE/V1,557 NXP Semiconductors, SAF1761BE/V1,557 Datasheet - Page 151

• 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
18.5.2 Implication
18.5.3 Workaround
18.6.1 Problem description
18.6 Errata added on 2009-04-20
Moderate
After performing a write access to the Endpoint Index or Control Function register, the
RD_N signal can only be asserted 60 ns after the WR_N signal is de-asserted (see
Figure
When a low-speed or full-speed device is attached, after some time, the low-speed or
full-speed device suddenly gets disconnected.
The following sequence is observed when the problem occurs:
Fig 33. Timing diagram for reading Endpoint Index register after performing a write
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The hub class driver detects a change of port status on the problematic port (through
the interrupt endpoint of the hub).
When a Get Port Status command is sent to the problematic port, the Port Enable bit
of the Port Status is cleared. This indicates that a port error has occurred. However,
the current connection status still indicates that a device is present on the port.
The hub driver sends a Port Reset command because of the clearing of the port
enable bit. This causes the disconnection of the attached device and its renumeration.
Before the hub driver detects the port status change, all active transfers on the
problematic port are halted.
Low-speed or full-speed devices connected to other ports are not affected when the
problem occurs.
The problem occurs with low-speed or full-speed devices.
When low-speed or full-speed devices are connected through a high-speed hub, the
problem will not occur.
During testing, it is observed that the problem always occurs on the port on which the
device was last attached.
A[17:1]
WR_N
CS_N
RD_N
33).
access
Rev. 01 — 18 November 2009
endpoint index
register
> 60 ns
Hi-Speed USB OTG controller
SAF1761
© NXP B.V. 2009. All rights reserved.
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