mc68hc908ld64 Freescale Semiconductor, Inc, mc68hc908ld64 Datasheet - Page 143

• Manufacturer Part Number: mc68hc908ld64
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

10.4.3 Echoing
10.4.4 Break Signal
MC68HC908LD64
Freescale Semiconductor
—
Rev. 3.0
The data transmit and receive rate can be anywhere from 4800 baud to
28.8 kbaud. Transmit and receive baud rates must be identical.
As shown in
received byte back to the PTA0 pin for error checking.
Any result of a command appears after the echo of the last byte of the
command.
A start bit followed by nine low bits is a break signal (see Figure 10-5).
When the monitor receives a break signal, it drives the PTA0 pin high for
the duration of two bits before echoing the break signal.
BREAK
SENT TO
MONITOR
START
$A5
BIT
ECHO
START
START
BIT
BIT
BIT 0
READ
Figure
BIT 0
BIT 0
Figure 10-3. Sample Monitor Waveforms
BIT 1
Monitor ROM (MON)
Figure 10-2. Monitor Data Format
BIT 1
BIT 1
Figure 10-4. Read Transaction
10-4, the monitor ROM immediately echoes each
READ
BIT 2
BIT 2
BIT 2
BIT 3
ADDR. HIGH
BIT 3
BIT 3
BIT 4
BIT 4
BIT 4
ADDR. HIGH ADDR. LOW ADDR. LOW
BIT 5
BIT 5
BIT 5
BIT 6
BIT 6
BIT 6
BIT 7
BIT 7
BIT 7
Functional Description
Monitor ROM (MON)
STOP
STOP
STOP
BIT
BIT
BIT
START
START
NEXT
NEXT
BIT
BIT
Data Sheet
RESULT
DATA
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