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CHAPTER 13 SERIAL INTERFACE (UART0)
Preliminary User’s Manual U16035EJ1V0UM
13.4.3 Infrared data transfer mode
In infrared data transfer mode, the following data format pulse output and pulse receiving are enabled. The
relationship between the main system clock and baud rate is shown in Table 13-3.
(1) Data format
Figure 16-11 compares the data format used in UART mode with that used in infrared data transfer mode.
The IR (infrared) frame corresponds to the bit string of the UART frame, which consists of pulses – a start bit,
eight data bits, and a stop bit.
The length of the electrical pulses that are used to transmit and receive in an IR frame is 3/16 the length of the
cycle time for one bit (i.e., the “bit time”). This pulse (whose width is 3/16 the length of one bit time) rises from
the middle of the bit time (see the figure below).
0
Start bit
1
D0
0
D1
1
D2
0
D3
0
D4
1
D5
1
D6
0
D7
1
Stop bit
UART frame
Data bits
Start bit
1
0
1
0
0
1
1
0
Stop bit
IR frame
Data bits
Pulse width =
3/16 bit time
Bit time
0
1
Bit time
Pulse width = 3/16 bit time
Figure 13-11. Data Format Comparison Between Infrared Data Transfer Mode and UART Mode