MMC2114 MOTOROLA [Motorola, Inc], MMC2114 Datasheet - Page 391

• Manufacturer Part Number: MMC2114
• Description: M CORE Microcontrollers
• Manufacturer: MOTOROLA [Motorola, Inc]

17.12.6.2 Address Mark Wakeup (WAKE = 1)
MMC2114 • MMC2113 • MMC2112 — Rev. 1.0
MOTOROLA
NOTE:
Serial Communications Interface Modules (SCI1 and SCI2)
When WAKE = 1, an address mark clears the RWU bit and wakes up the
receiver. An address mark is a 1 in the most significant data bit position.
The receiver interprets the data as address data. When using address
mark wakeup, the MSB of all non-address data must be 0. User code
must compare the address data to the receiver’s address and, if the
addresses match, the receiver processes the frames that follow. If the
addresses do not match, user code must put the receiver back to sleep
by setting the RWU bit. The RWU bit remains set and the receiver
remains on standby until another address frame appears on the RXD
pin.
The address mark clears the RWU bit before the stop bit is received and
sets the RDRF flag.
Address mark wakeup allows messages to contain idle frames but
requires that the most significant byte (MSB) be reserved for address
data.
With the WAKE bit clear, setting the RWU bit after the RXD pin has been
idle can cause the receiver to wake up immediately.
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
Serial Communications Interface Modules (SCI1 and SCI2)
Advance Information
Receiver
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