MC68HC908AP16CFB datasheet(234/440 Pages) MOTOROLA

234 / 440 page

Serial Communications Interface

Data Sheet

MC68HC908AP Family — Rev. 2.5

234

MOTOROLA

M — Mode (Character Length) Bit

This read/write bit determines whether SCI characters are eight or

nine bits long. (See Table 13-5.) The ninth bit can serve as an extra

stop bit, as a receiver wakeup signal, or as a parity bit. Reset clears

the M bit.

1 = 9-bit SCI characters

0 = 8-bit SCI characters

WAKE — Wakeup Condition Bit

This read/write bit determines which condition wakes up the SCI: a

logic 1 (address mark) in the most significant bit position of a received

character or an idle condition on the RxD pin. Reset clears the WAKE

bit.

1 = Address mark wakeup

0 = Idle line wakeup

ILTY — Idle Line Type Bit

This read/write bit determines when the SCI starts counting logic 1s

as idle character bits. The counting begins either after the start bit or

after the stop bit. If the count begins after the start bit, then a string of

logic 1s preceding the stop bit may cause false recognition of an idle

character. Beginning the count after the stop bit avoids false idle

character recognition, but requires properly synchronized

transmissions. Reset clears the ILTY bit.

1 = Idle character bit count begins after stop bit

0 = Idle character bit count begins after start bit

PEN — Parity Enable Bit

This read/write bit enables the SCI parity function. (See Table 13-5.)

When enabled, the parity function inserts a parity bit in the most

significant bit position. (See Figure 13-3.) Reset clears the PEN bit.

1 = Parity function enabled

0 = Parity function disabled

Freescale Semiconductor, Inc.

For More Information On This Product,

Go to: www.freescale.com

MC68HC908AP16CFB Datasheet(PDF) 234 Page - Motorola, Inc