S42
Hardware User Guide
1VV0301303 Rev. 11
Page 21 of 85
2021-05-06
Not Subject to NDA
UART-TXD
GND
UART-RXD
IUC_IN# / CTS#
UART-RXD
UART-TXD
B
lu
eM
o
d
+
Sx
H
o
st
CTS#
IUC_OUT# / RTS#
IUR_OUT#
IUR_IN#
Figure 9: UART Interface without UICP Signals 4-wire (incl. GND)
Warning: UICP must be deactivated permanently in this
configuration, because signal UART-CTS# and IUR-IN# become
inputs with no PU or PD if UICP is active. This would cause floating
CMOS inputs.
Note/Tip: This configuration is not recommended because it may
cause a loss of data.
Note/Tip: It is strongly recommended to use hardware flow control
in both directions. Not using flow control can cause a loss of data.