mc68181 Freescale Semiconductor, Inc, mc68181 Datasheet - Page 70

• Manufacturer Part Number: mc68181
• Description: Signal Processor
• Manufacturer: Freescale Semiconductor, Inc

MC68181
Host-to-Decoder Packet Descriptions
B-10
SYNCHRONOUS MODE ENABLE (SME)
MAXIMUM OFF TIME (MOT)
CLOCK OUTPUT DISABLE (COD)
MINUTE TIMER ENABLE (MTE)
LOW BATTERY POLARITY (LBP)
SP
0
0
1
1
1
When this bit is set, a Status Packet will be automatically sent whenever the SMU
(Synchronous Mode Update) bit in the Status Packet is set. The host can use the SM
(Synchronous Mode) bit in the Status Packet as an in-range/out-of-range indication.
The value after reset = 0.
This bit has no effect if AST in the Timing Control Packet is non-zero. When AST = 0
and MOT = 0, asynchronous A-word searches will time-out in 4 minutes. When
AST = 0 and MOT = 1, asynchronous A-word searches will time-out in 1 minute.
(value after reset = 0)
When this bit is clear, a 38.4 kHz signal will be output on the CLKOUT pin. When this
bit is set, the CLKOUT pin will be driven low. Note that setting and clearing this bit
can cause pulses on the CLKOUT pin that are less than one half the 38.4 kHz period.
Also note that when the clock output is enabled, the CLKOUT pin will always output
the 38.4 kHz signal even when the FLEX chip IC is in reset (as long as the FLEX chip
IC oscillator is seeing clocks). The value after reset = 0.
When this bit is set, a Status Packet will be sent at one minute intervals with the MT
(Minute Time-out) bit in the Status Packet set. When this bit is clear, the internal one-
minute timer stops counting. The internal one-minute timer is reset when this bit is
changed from 0 to 1 or when the MTC (Minute Timer Clear) bit in the Control Packet
is set. The value after reset = 0.
This bit defines the polarity of the FLEX chip ICs LOBAT pin. The LB bit in the Status
Packet is initialized to the inverse value of this bit when the FLEX chip IC is turned on
(by setting the ON bit in the Control Packet). When the FLEX chip IC is turned on, a
low battery update is sent to the host in the Status Packet when a low battery
condition is detected on the LOBAT pin. Setting this bit means that a high on the
LOBAT pin indicates a low voltage condition. The value after reset = 0.
SP
0
1
0
1
0
Inverted
Inverted
Normal
Normal
Signal Polarity
EXTS1 EXTS0
MC68181 Technical Data Sheet
Freescale Semiconductor, Inc.
For More Information On This Product,
Table B-6 SP Bit Definition
Inverted
Inverted
Normal
Normal
Go to: www.freescale.com
FSK Modulation
@ SP = 0,0
+4800 Hz
+1600 Hz
–1600 Hz
–4800 Hz
EXTS1
1
1
0
0
MOTOROLA
EXTS0
0
1
1
0