st92f124 STMicroelectronics, st92f124 Datasheet - Page 213

• Manufacturer Part Number: st92f124
• Description: 8/16-bit Single Voltage Flash Mcu Family With Ram, E3 Tmemulated Eeprom, Can 2.0b And J1850 Blpd
• Manufacturer: STMicroelectronics

MULTIPROTOCOL SERIAL COMMUNICATIONS INTERFACE (Cont’d)
10.5.4 SCI-M Operating Modes
10.5.4.1 Asynchronous Mode
In this mode, data and clock can be asynchronous
(the transmitter and receiver can use their own
clocks to sample received data), each data bit is
sampled 16 times per clock period.
The baud rate clock should be set to the ÷16 Mode
and the frequency of the input clock (from an ex-
ternal source or from the internal baud-rate gener-
ator output) is set to suit.
Figure 108. Sampling Times in Asynchronous Format
SDIN
rcvck
rxclk
LEGEND:
SIN:
rcvck:
rxd:
rxclk:
rxd
Serial Data Input line
Internal X16 Receiver Clock
Internal Serial Data Input Line
Internal Receiver Shift Register Sampling Clock
0
MULTIPROTOCOL SERIAL COMMUNICATIONS INTERFACE (SCI-M)
1
2
3
4
5
10.5.4.2
Synchronous Clock
In this mode, data and clock are synchronous,
each data bit is sampled once per clock period.
For transmit operation, a general purpose I/O port
pin can be programmed to output the CLKOUT
signal from the baud rate generator. If the SCI is
provided with an external transmission clock
source, there will be a skew equivalent to two
INTCLK periods between clock and data.
Data will be transmitted on the falling edge of the
transmit clock. Received data will be latched into
the SCI on the rising edge of the receive clock.
7
8
9
Asynchronous
10
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12
13
14
Mode
15
VR001409
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with
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