HD6413308 Hitachi Semiconductor, HD6413308 Datasheet - Page 208

• Manufacturer Part Number: HD6413308
• Description: Hitachi Single-Chip MicroComputer
• Manufacturer: Hitachi Semiconductor

Table 9-7. Data Formats in Asynchronous Mode
SMR bits
CHR
0
0
0
0
1
1
1
1
Note
(2) Clock: In the asynchronous mode it is possible to select either an internal clock created by the
on-chip baud rate generator, or an external clock input at the ASCK pin. Refer to Table 9-6.
If an external clock is input at the ASCK pin, its frequency should be 16 times the desired baud
rate.
If the internal clock provided by the on-chip baud rate generator is selected and the ASCK pin is
used for clock output, the output clock frequency is equal to the baud rate, and the clock pulse rises
at the center of the transmit data bits. Figure 9-3 shows the phase relationship between the output
clock and transmit data.
START: Start bit
STOP: Stop bit
P: Parity bit
PE
0
0
1
1
0
0
1
1
Figure 9-3. Phase Relationship Between Clock Output and Transmit Data
STOP
0
1
0
1
0
1
0
1
Output clock
Transmit data
Data format
START
START
START
START
START
START
START
START
Start bit
8-Bit data
8-Bit data
8-Bit data
8-Bit data
7-Bit data
7-Bit data
7-Bit data
7-Bit data
195
D1
D2
STOP
STOP
P
P
D3
STOP
STOP
P
P
STOP
STOP
STOP
STOP
STOP
STOP STOP
STOP