User's Manual

M50 Hardware Design
M50_HD_V2.0 - 42 -
The Debug Port
 DBG_TXD: Send data to the COM port of computer.
 DBG_RXD: Receive data from the COM port of computer.
The Auxiliary UART Port
 TXD_AUX: Send data to the RXD of DTE.
 RXD_AUX: Receive data from the TXD of DTE.
The logic levels are described in the following table.
Table 10: Logic levels of the UART interfaces
Parameter Min Max Unit
V
IL
0 0.25×VDD_EXT V
V
IH
0.75×VDD_EXT VDD_EXT +0.3 V
V
OL
0.15×VDD_EXT V
V
OH
0.85×VDD_EXT V
Table 11: Pin definition of the UART interfaces
Interface Name Pin Description
Debug Port
DBG_RXD 43 Receive data of the debug port
DBG_TXD 42 Transmit data of the debug port
UART Port
RI 46 Ring indicator
RTS 51 Request to send
CTS 48 Clear to send
RXD 50 Receive data of the UART port
TXD 49 Transmit data of the UART port
DTR 47 Data terminal ready
DCD 45 Data carrier detection
Auxiliary UART Port
RXD_AUX 41 Receive data of the Auxiliary UART
TXD_AUX 40 Transmit data of the Auxiliary UART
3.9.1. UART Port
3.9.1.1. The features of UART Port.
 Seven lines on UART interface
 Contain data lines TXD and RXD, hardware flow control lines RTS and CTS, other control
lines DTR, DCD and RI.
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