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XC161 Derivatives
Peripheral Units (Vol. 2 of 2)
Asynchronous/Synchronous Serial Interface (ASC)
User’s Manual
18-5
V2.2, 2004-01
ASC_X, V2.0
18.2
Asynchronous Operation
Asynchronous Mode supports full-duplex communication in which both transmitter and
receiver use the same data frame format and the same baudrate. Data is transmitted on
line TxD and received on line RxD. IrDA data transmission/reception is supported up to
115.2 kbit/s.
shows the block diagram of the ASC when operating in
Asynchronous Mode.
Figure 18-3
Asynchronous Mode of Serial Channel ASC
Serial Port Control
MCA05434
13-bit Reload Register
13-bit Baudrate Timer
16
f
BRT
f
BR
f
DIV
CON.FDE
MUX
CON.BRS
Fractional
Divider
2
3
CON.R
f
ASC
Autobaud Detection
Autobaud
Start Int.
Autobaud
Detect Int.
ABSTIR
ABDETIR
CON.REN
CON.FEN
CON.PEN
CON.OEN
CON.LB
Shift Clock
FIFO
Control
Shift Clock
CON.OE
TIR
TBIR
EIR
Receive Int.
Request
Transmit Buffer
Int. Request
CON.PE
CON.FE
CON.STP
CON.M
CON.ODD
RIR
Transmit Int.
Request
Error Int.
Request
Receive Buffer Reg.
RBUF
Transmit Buffer Reg.
TBUF
Receive Shift
Register
Transmit Shift
Register
IrDA
Coding
MU
X
Sampling
MUX
MU
X
IrDA
Decoding
Internal Bus
MUX
1
TxD
1
RxD