Toradex Verdin - UART Signals; Reference Schematics

Verdin Carrier Board Design Guide
Preliminary – Subject to Change
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2.10.1 UART Signals
Verdin
Pin
Verdin
Signal Name
I/O
Type
Power
Rail
Description
129
UART_1_RXD
I
CMOS
1.8V
Received Data of general purpose UART_1
131
UART_1_TXD
O
CMOS
1.8V
Transmitted Data of general purpose UART_1
137
UART_2_RXD
I
CMOS
1.8V
Received Data of general purpose UART_2
139
UART_2_TXD
O
CMOS
1.8V
Transmitted Data of general purpose UART_2
147
UART_3_RXD
I
CMOS
1.8V
Received Data for main OS debug UART_3
149
UART_3_TXD
O
CMOS
1.8V
Transmitted Data for main OS debug UART_3
Table 22: "Always Compatible" UART Signals
Verdin
Pin
Verdin
Signal Name
I/O
Type
Power
Rail
Description
133
UART_1_RTS
O
CMOS
1.8V
Request to Send of general purpose UART_1
135
UART_1_CTS
I
CMOS
1.8V
Clear to Send of general purpose UART_1
141
UART_2_RTS
O
CMOS
1.8V
Request to Send of general purpose UART_2
143
UART_2_CTS
I
CMOS
1.8V
Clear to Send of general purpose UART_2
151
UART_4_RXD
I
CMOS
1.8V
Received Data for real time core debug UART_4
153
UART_4_TXD
O
CMOS
1.8V
Transmitted Data for real time core debug UART_4
Table 23: "Reserved" UART Signals
2.10.2 Reference Schematics
2.10.2.1 RS232 Reference Schematics
The RS232 interface can be classified as Data Terminal Equipment (DTE) or Data Communication
Equipment (DCE). This classification is inherited from the usage of the interface for modems. The
signal direction of these modes is different. Some Verdin modules might allow changing the mode
and therefore also the data direction, but this is not a mandatory requirement. According to the
Verdin specifications, the interface is intent to be used in the DTE configuration.
Signal
Name
Usage
DTE Direction
(Verdin
standard)
DCE Direction
UART_1_RXD
Received Data
Data from DCE to DTE
Input
Output
UART_1_TXD
Transmitted Data
Data from DTE to DCE
Output
Input
UART_1_RTS
Request to Send
DTE request to DCE to be prepared to
receive data
Output
Input
UART_1_CTS
Clear to Send
DCE indicates ready to accept data
Input
Output
Table 24: RS232 Signal Modes