isp1161bm NXP Semiconductors, isp1161bm Datasheet - Page 85

• Manufacturer Part Number: isp1161bm
• Description: Isp1161 Full-speed Universal Serial Bus Single-chip Host And Device Controller
• Manufacturer: NXP Semiconductors

Philips Semiconductors
9397 750 09567
Product data
11.4.3 Resume conditions
After wake-up from ‘suspend’ state, all internal registers except the Unlock register
are read and write protected. A special unlock operation is needed to re-enable write
access. This prevents data corruption during power-up of external components.
Figure 40
powered-off mode. The SUSPEND output is used to switch off power to the
microprocessor and other external circuits during ‘suspend’ state. The ISP1161’s DC
is woken up via the USB bus (global resume) or by the ring detection circuit on the
telephone line.
Wake-up from ‘suspend’ state is initiated either by the USB host or by the application:
The steps of a wake-up sequence are as follows:
•
•
1. The internal oscillator and the PLL multiplier are re-enabled. When stabilized, the
2. The D_SUSPEND output is de-asserted and the RESUME bit in the DcInterrupt
3. Maximum 15 ms after starting the wake-up sequence the ISP1161’s DC resumes
4. In case of a remote wake-up ISP1161’s DC drives a K-state on the USB bus for
5. Following the de-assertion of output D_SUSPEND, the application restores itself
6. After wake-up the internal registers of ISP1161’s DC are read and write protected
Fig 40. ISP1161’s DC SUSPEND and WAKEUP signals in a powered-off modem
USB host: drives a K-state on the USB bus (global resume)
Application: remote wake-up via a HIGH level on input WAKEUP or a LOW level
on input CS (if enabled via bit WKUPCS in the DcHardwareConfiguration register).
Wake-up on CS will work only if V
clock signals are routed to all internal circuits of the ISP1161’s DC.
Register is set. This will generate an interrupt if bit IERESUME in the
DcInterruptEnable Register is set.
its normal functionality.
10 ms.
and other system components to normal operating mode.
to prevent corruption by inadvertent writing during power-up of external
components. The firmware must send an Unlock Device command to the
ISP1161’s DC to restore its full functionality. See
application.
shows a typical bus-powered modem application using ISP1161’s DC in
USB
Rev. 02 — 13 December 2002
V BUS
D_DP
D_DM
ISP1161
D_SUSPEND
Full-speed USB single-chip host and device controller
D_WAKEUP
V CC
BUS
is present.
power
switch
RING DETECTION
V CC
CONTROLLER
Section 13.3.2
© Koninklijke Philips Electronics N.V. 2002. All rights reserved.
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004aaa033
ISP1161
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