MC68HC08AS32 Datasheet, PDF (263/394 Pages) Motorola, Inc – M68HC08 Family of 8-bit microcontroller units (MCUs)

Serial Communications Interface (SCI)
I/O Registers
RWU — Receiver Wakeup Bit
This read/write bit puts the receiver in a standby state during which
receiver interrupts are disabled. The WAKE bit in SCC1 determines
whether an idle input or an address mark brings the receiver out of the
standby state and clears the RWU bit. Reset clears the RWU bit.
1 = Standby state
0 = Normal operation
SBK — Send Break Bit
Setting and then clearing this read/write bit transmits a break
character followed by a logic 1. The logic 1 after the break character
guarantees recognition of a valid start bit. If SBK remains set, the
transmitter continuously transmits break characters with no logic 1s
between them. Reset clears the SBK bit.
1 = Transmit break characters
0 = No break characters transmitted
NOTE:
Do not toggle the SBK bit immediately after setting the SCTE bit
because toggling SBK too early causes the SCI to send a break
character instead of a preamble.
17.9.3 SCI Control Register 3
SCI control register 3:
• Stores the ninth SCI data bit received and the ninth SCI data bit to
be transmitted
• Enables these interrupts:
– Receiver overrun interrupts
– Noise error interrupts
– Framing error interrupts
– Parity error interrupts
MC68HC08AS32 — Rev. 3.0
MOTOROLA
Serial Communications Interface (SCI)
Advance Information
263