MC912DG128A Motorola, MC912DG128A Datasheet - Page 229

• Manufacturer Part Number: MC912DG128A
• Description: Microcontrollers
• Manufacturer: Motorola

7-msi
MOTOROLA
LOOPS RSRC DDRS1(3) WOMS
0
1
1
1
1
1
1
0
0
0
1
1
1
x
0
1
1
0
1
1
x
RSRC — Receiver Source
M — Mode (select character format)
WAKE — Wake-up by Address Mark/Idle
ILT — Idle Line Type
When LOOPS = 1, the RSRC bit determines the internal feedback
path for the receiver.
Determines which of two types of idle line detection will be used by
the SCI receiver.
In the short mode, the SCI circuitry begins counting ones in the search
for the idle line condition immediately after the start bit. This means
that the stop bit and any bits that were ones before the stop bit could
be counted in that string of ones, resulting in earlier recognition of an
idle line.
0 = Receiver input is connected to the transmitter internally (not
1 = Receiver input is connected to the TXD pin
0 = One start, eight data, one stop bit
1 = One start, eight data, ninth data, one stop bit
0 = Wake up by IDLE line recognition
1 = Wake up by address mark (last data bit set)
0 = Short idle line mode is enabled.
1 = Long idle line mode is detected.
0/1
x
1
1
x
0
1
Table 34 Loop Mode Functions
TXD pin)
Normal Operations
LOOP mode without TXD output(TXD = High Impedance)
LOOP mode with TXD output (CMOS)
LOOP mode with TXD output (open-drain)
Single wire mode without TXD output
Single wire mode with TXD output
Single wire mode for the receiving and transmitting(open-drain)
(the pin is used as receiver input only, TXD = High Impedance)
(the output is also fed back to receiver input, CMOS)
Multiple Serial Interface
Function of Port S Bit 1/3
Serial Communication Interface (SCI)
MC68HC912DT128A Rev 2.0
Multiple Serial Interface
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