Specifications

SCI Multiprocessor Communication

8-13

Serial Communications Interface (SCI)

3) Since TXSHF and WUT are both double-buffered, SCITXBUF and

TXWAKE can be written to immediately after TXSHF and WUT are loaded.

4) To transmit non-address frames in the block, leave the TXWAKE bit set

to 0.

Note: Address-bit format for transfers of 11 bytes or less

As a general rule, the address-bit format is typically used for data frames of

11 bytes or less. This format adds one bit value (1 for an address frame, 0

for a data frame) to all data bytes transmitted. The idle-line format is typically

used for data frames of 12 bytes or more.

Figure 8–5. Address-Bit Multiprocessor Communication Format

MSB Parity

Addr Data

Addr

Data format

(Pins SCIRXD, SCITXD)

Data format expanded

First frame within

block Is address

(Address bit is 1)

Idle time is of

no significance

Next frame is address

for next block

(Address bit is 1)

Start

LSB Stop

Address-bit mode frame example

Address bit

Frame within block

(Address bit is 0)

Start

One block

Idle periods of no significance

Blocks of frames