Synchronous Operation - Infineon Technologies TC1728 User Manual

17.1.4

Synchronous Operation

Synchronous Mode supports half-duplex communication, usable for simple I/O
expansion via shift registers. Data is transmitted and received via pin RXD while pin TXD
outputs the shift clock. These signals are typically connected as alternate functions with
GPIO port pins. Synchronous Mode is selected with CON.M = 000
Eight data bits are transmitted or received synchronous to a shift clock generated by the
internal baud rate generator. The shift clock is active only as long as data bits are
transmitted or received.
f
ASC
TXD
0
MUX
RXD
1
Figure 17-6 Synchronous Mode of Serial Channel ASC
User's Manual
ASC, V1.3 2007-11
Asynchronous/Synchronous Serial Interface (ASC)
2
MUX
3
R
BRS
M = 000
REN
OEN
Serial Port Control
LB
Shift Clock
Receive Shift
Register
Receive
Buffer Reg.
RBUF
Internal Bus
13-bit Reload Register
f
DIV
13-bit Baud Rate Timer
OE
B
Receive Int. Req.
Shift Clock
Transmit Int. Req.
Transmit Buffer Int. Req.
Error Int. Req.
Transmit Shift
Register
Transmit
Buffer Reg.
TBUF
17-9
TC1728
.
B
f
BR
4
f
BRT
RIR
TIR
TBIR
EIR
MCA06205
V1.0, 2011-12