Motorola MC68HC05RC16 用户手册

Carrier Modulator Transmitter (CMT)

Modulator

MC68HC05RC16 — Rev. 3.0

General Release Specification

MOTOROLA

Carrier Modulator Transmitter (CMT)

81

EIMSK — External Interrupt Mask

The external interrupt mask bit is used to mask IRQ and keyscan
interrupts. This bit is cleared by reset.

1 = IRQ and keyscan interrupts masked
0 = IRQ and keyscan interrupts enabled

EXSPC — Extended Space Enable

For a description of the extended space enable bit, see

. This bit is cleared by reset.

1 = Extended space enabled
0 = Extended space disabled

BASE — Baseband Enable

When set, the BASE bit disables the carrier generator and forces the
carrier output high for generation of baseband protocols. When BASE
is clear, the carrier generator is enabled and the carrier output toggles
at the frequency determined by values stored in the carrier data
registers. See

. This bit is cleared by reset. This bit

is not double buffered and should not be written to during a
transmission.

1 = Baseband enabled
0 = Baseband disabled

MODE — Mode Select

For a description of CMT operation in time mode, see

. This bit is cleared by reset. This bit is not double buffered

and should not be written to during a transmission.

1 = CMT operates in FSK mode.
0 = CMT operates in time mode.

IE — Interrupt Enable

A CPU interrupt will be requested when EOC is set if IE was
previously set. If IE is clear, EOC will not request a CPU interrupt.

1 = CPU interrupt enabled
0 = CPU interrupt disabled