Renesas M16C FAMILY, Руководство пользователя

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Rev.2.00 Oct 16, 2006 page 68 of 354
REJ09B0340-0200
M30245 Group 2. UART
In receiving data in UART mode, choose functions from those listed in Table 2.4.5. Operations of the
circled items are described below. Figure 2.4.10 shows the operation timing, and Figures 2.4.11 and
2.4.12 show the set-up procedures.
2.4.3 Operation of Serial I/O (reception in UART mode)
Table 2.4.5. Choosed functions
Item Set-up
Transfer clock
source Internal clock (f
1
/ f
8
/ f
32
)
External clock (CLKi pin)
RTS function RTS function enabled
RTS function disabled
O
O
Item Set-up
Data logic select
function
No reverse
Reverse
O
T
X
D, R
X
D I/O
polarity reverse bit
No reverse
Reverse
O
Bus collision
detection function
O
Not selected
Selected
(1) Setting the receive enable bit to “1” readies data-receivable status. At this time, output from
________
the RTSi pin goes to “L” level to inform the transmission side that the receivable status is
ready.
(2) When the first bit (the start bit) of reception data is received from the RxDi pin, output from the
_______
RTS goes to “H” level. Then, data is received, bit by bit, in sequence: LSB, ····, MSB, and stop
bit(s).
(3) When the stop bit(s) is (are) received, the content of the UARTi receive register is transmitted
to the UARTi receive buffer register. At this time, the receive complete flag goes to “1” to
indicate that the reception is completed, the UARTi receive interrupt request bit goes to “1”,
_______
and output from the RTS pin goes to “L” level.
(4) The receive complete flag goes to “0” when the lower-order byte of the UARTi buffer register
is read.
• Set RxDi pin's port direction register to “0”.
Operation
Note