LEXI-R422 - System integration manual
UBX-23007449 - R02
System description
Page 10 of 108
C1-Public
Function Name
No
ID
I/O Description
Remarks
UART
RXD
4
E1
O
UART data
output
Primary UART circuit 104 (RxD) in ITU-T V.24,
for AT commands, data, Mux, FOAT.
See section
for functional description.
See section
for external circuit design-in.
TXD
5
F1
I
UART data input Primary UART circuit 103 (TxD) in ITU-T V.24,
for AT commands, data, Mux, FOAT.
Internal active pull-up to V_INT.
See section
for functional description.
See section
for external circuit design-in.
CTS
6
G1
O
UART clear to
send output
Primary UART circuit 106 (CTS) in ITU-T V.24.
See section
for functional description.
See section
for external circuit design-in.
RTS
7
H1
I
UART request to
send input
Primary UART circuit 105 (RTS) in ITU-T V.24.
Internal active pull-up to V_INT.
See section
for functional description.
See section
for external circuit design-in.
DSR
11
M1
O /
I
UART data set
ready output /
AUX UART
request to send
input
Primary UART circuit 107 (DSR) in ITU-T V.24,
configurable as auxiliary UART RTS input.
See section
for functional description.
See section
for external circuit design-in.
RI
10
L1
O /
O
UART ring
indicator output /
AUX UART clear
to send output
Primary UART circuit 125 (RI) in ITU-T V.24,
configurable as auxiliary UART CTS output.
See section
for functional description.
See section
for external circuit design-in.
DTR
9
K1
I /
I
UART data
terminal ready
input /
AUX UART data
input
Primary UART circuit 108/2 (DTR) in ITU-T V.24,
configurable as auxiliary UART TxD input.
Internal active pull-up to V_INT.
See section
for functional description.
See section
for external circuit design-in.
DCD
8
J1
O /
O
UART data carrier
detect output /
AUX UART data
output
Primary UART circuit 109 (DCD) in ITU-T V.24,
configurable as auxiliary UART RxD output.
See section
for functional description.
See section
for external circuit design-in.
USB
USB_5V0
22
R10
I
USB detect input VBUS sense input pin to enable the USB interface.
See section
for functional description.
See section
for external circuit design-in.
Provide test point for FW update and diagnostic.
USB_3V3
19
R7
I
USB supply input VBUS supply input pin to supply the USB interface.
See section
for functional description.
See section
for external circuit design-in.
Provide test point for FW update and diagnostic.
USB_D-
20
R8
I/O USB Data Line D- USB available only for FW update and diagnostic.
90
nominal differential impedance.
See section
for functional description.
See section
for external circuit design-in.
Provide test point for FW update and diagnostic.
USB_D+
21
R9
I/O USB Data Line D+ USB available only for FW update and diagnostic.
90
nominal differential impedance.
See section
for functional description.
See section
for external circuit design-in.
Provide test point for FW update and diagnostic.
